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Hans Wilsdorf and Rolex

Copyright © David Boettcher 2006 - 2019 all rights reserved.

What this page is about: I became interested in wristwatches and watches in general as a result of inheriting my grandparents’ Rolex wristwatches, images of which you can see on the Home and Contact Me pages, and on this page. The were made around 1917/1918, the time of the Great War. In broad terms the history of the Rolex Watch Company can be divided into two parts: an early phase when they were trying lots of different ideas, and a later phase when they had hit upon a successful course. The boundary two phases is pretty well delineated by the Second World War, 1939 to 1945. After the war, Rolex created many iconic models of watches under a single brand, Rolex. Before the war, the situation is much less clear cut and there were attempts to create other brands that were separate from, but somehow associated, with the Rolex name. I am interested in the first phase, the creation of the Rolex brand and the pre-war history of the company and that is mainly what this page is about. I hope you find it interesting. If you have any questions or comments, please don't hesitate to contact me via my Contact Me page.

The story of the Rolex watch is inextricably entwined with the story of Hans Wilsdorf, who co-founded and personally drove forward the progress of the company, and the technical developments that led to the public acceptance and expectation of an accurate, waterproof, self winding wristwatch. Many other companies and individuals contributed, and there were waterproof and self winding watches before the Rolex Oyster, but the fact remains than Wilsdorf is an important figure in the story of the modern mechanical wristwatch.

Hans Wilsdorf
Hans Wilsdorf
The four volumes of the Rolex Jubilee Vade Mecum
The four volumes of the Rolex Jubilee Vade Mecum: Click Image to Enlarge.

The picture of Hans Wilsdorf is from the Rolex Jubilee Vade Mecum published by the Rolex Watch Company in 1946. The Vade Mecum takes the form of four small booklets in a slip case shown in the smaller image, which you can click to enlarge. It was printed in a limited edition of 1,000. The booklets are:

I have copy number 619, except for volume three which is from copy number 270. All four booklets are stamped "Rolex Watch Division, C.P.O. Box 721, Tokyo, Japan" so I guess they must have all been in the same office at one time and one got switched around. If the owner of Rolex Vade Mecum 270 reads this and wants to swap volume three, then please get in touch!

Hans Wilsdorf - Early Days

Hans Wilsdorf was born in Kulmbach, Bavaria, Franconia (Germany) on 22 March 1881, the second son of a family of three. His mother's early death was soon followed by that of his father and, in 1893 when he was 12, his uncles decided to liquidate his father's business and use the proceeds to place the children in a very good boarding school in Coburg. Wilsdorf showed a particular liking for mathematics and languages, which later drove him to travel and work in foreign countries. He apprenticed at a firm of pearl exporters whose sales organisation covered the whole world, which experience he felt was invaluable throughout his whole career.

In 1900, aged 19, Wilsdorf started work at the watch exporting firm Cuno Korten of 49 rue Léopold Robert, La Chaux-de-Fonds, Switzerland, as their English language correspondent and clerk at a monthly salary of 80 francs. Wilsdorf says that Cuno Korten was a ‘big concern’ exporting about one million francs worth of watches annually.

Outside of the long established watch making centre of Geneva, La Chaux de Fonds and Le Locle formed the hub of the Swiss Jura watchmaking industry at the time. It was a French speaking area of Switzerland so Wilsdorf would have to have spoken Swiss French in addition to his native German and English. In La Chaux-de-Fonds and the nearby Le Locle, Wilsdorf was exposed to the most influential people and companies in Swiss watchmaking, which would later be an important asset in the founding and success of his own business in London, which became the Rolex Watch Company.

Cuno Korten
Cuno Korten

There seems to be nothing known about Cuno Korten. The only thing I could find is the advert from 1904 reproduced here, which says that M. Bechman of the London company Baer, Bechmann & Co. Ltd. will be in Switzerland from 1 August, and that proposals of meetings can be made via Monsieur Cuno Korten of 49 rue Léopold Robert, La Chaux-de-Fonds. This was evidently a trip by Bechmann to find new lines of goods, clocks or watches, to import, and the mention of M. Korten suggests that he was facilitating meetings with Swiss manufacturers and was possibly the Swiss agent for Baer, Bechmann & Co. Ltd. Wilsdorf's English language skills would have been useful in communicating between the English and Swiss offices. Baer and Bechmann themselves would have almost certainly spoken German, but the Swiss watchmaking districts were then still mainly in the French speaking Jura and Geneva.

There is little trace of the many companies that operated in London as import agents for Swiss watch manufacturers in the late nineteenth and early twentieth centuries. Their main tasks were taking samples round to watch retailers, usually jewellers shops, and recording orders, which would be amalgamated and sent on to the watch manufacturers. There were no restrictions on the import of Swiss watches, especially after Gladstone reduced import duties in the 1860s, and before 1907 there was no requirement that gold or silver watch cases be hallmarked. Today agents for foreign manufacturers often simply send in the orders and receive their commissions, with the manufacturer taking responsibility for delivering the goods and invoicing the customer, but in those days the agent would collect parcels of watches from the shipping agent, paying any import duties, and send the watches on the customers who had ordered them. The appearance of Baer's name in a number of bankruptcies and financial arrangements shows that agents were also responsible for collecting the money from the customer. But it was relatively easy business with little capital involved; all that was needed was an ability to speak English and Swiss French or German, an office, and a working arrangement with one or more Swiss watch manufacturers.

Bernard, or Bernhard, Baer is recorded at 52 Hatton Garden, London, in 1887, where Bechmann & Baer were later listed as clock manufacturers, although they were really importers rather than actual manufacturers. The business was converted into a limited liability company as Baer, Bechmann & Co. Ltd. at 55 Hatton Gardens on 12 March 1902.

By 1913 Baer, Bechmann & Co. Ltd. had disappeared; incorporated into Junghans Brothers Ltd., clock manufacturers, at the same 55 Hatton Gardens address. The London company Junghans Brothers Ltd. went into voluntary liquidation in 1932, no doubt a victim of the severe financial depression that followed the Wall Street crash of 1929.

Foundation of Wilsdorf & Davis

In 1903 Wilsdorf moved to London, where he said that he worked for a ‘good watchmaking firm’ which by 1946, when he wrote the Vade Mecum, had long since closed down. The name of this firm is not mentioned but it seems likely that it was one of the companies that imported Swiss watches and sold them to British retailers. Given the connection between Cuno Korten and Baer, Bechmann & Co. Ltd., it seems quite likely that Baer, Bechmann was the London company alluded to by Wilsdorf, and the date of the disappearance of that company in 1913 would fit his statement in 1946 that they had long since closed down.

Growing in confidence with the experience he gained from this and his previous employment, two years after arriving in London Wilsdorf set about establishing his own business. In May 1905 at the age of 24, he borrowed money from his sister and brother-in-law Alfred Davis, and founded the firm of Wilsdorf & Davis, 83 Hatton Gardens, London E.C.

In the beginning Wilsdorf & Davis did not concentrate solely on the top end watches that Rolex would later become known for. They imported a wide range of items that could be sold at different price points. Their first speciality was a travelling watch, called a portfolio watch, cased in fine quality leather. The wristwatches that they imported from Aegler were their ‘top of the range’ items. When the name Rolex was introduced it was reserved for use on Aegler lever watches, although even these were sometimes made with only seven jewels rather than fully jewelled with 15 or more.

Wilsdorf & Davis also bought watches from other manufacturers, and not always lever quality. Watches with cylinder escapement movements are seen with the W&D sponsor's mark, indicating that they were imported by Wilsdorf & Davis, although these were never branded with the Rolex name. The cylinder escapement was mass produced by the Swiss watch industry in the nineteenth century. It was cheap and robust, but inferior to the lever escapement.

W&D Sponsor's Mark

Wilsdorf & Davis were not watch manufacturers; they purchased watches from Swiss manufacturers and sold them on to retailers, at first with no branding at all. Then in 1907 British law changed and required that all imported gold and silver watch cases be hallmarked in a British Assay office. This caused Wilsdorf & Davis to register a sponsor's mark, the 'W&D' mark, with the London Assay office, which was then punched into watch cases before they were sent in for assay and hallmarking. A registered sponsor's mark is the vital first step in the process of assay and hallmarking. If an item does not carry a recognised sponsor's mark, it will simply not be received by the assay office. When you are considering a set of marks that you think might be a hallmark, remember that there must be a sponsor's mark.

This forced adoption of the W&D sponsor's mark, something that also happened to look like a trademark, is quite possibly what started Wilsdorf thinking about branding and marketing. It is the first such mark registered by Wilsdorf & Davis, and the same mark is also seen on stamped on to watch movements, which was not required by British law.

None of the items imported by Wilsdorf and Davis before 1907 are known; they were, and still are, anonymous with no name or branding at all. Wilsdorf in all likelihood thought of them as simple commodities from the import of which he could take a financial profit but no pride — they could equally well have been grain or sugar or any other commodity. But seeing watch cases stamped with the W&D mark would naturally have caused him some pride, here was some way that the goods that he dealt with would be recognised, which would create a reputation for his business. And a good reputation is valuable, something to be nurtured and cared for.

Wilsdorf and Early Wristwatches

In the Vade Mecum Wilsdorf says that he became convinced that the wristwatch was the way of the future. He thought there would be a better trade in wristwatches than pocket watches, partly because they were more prone to damage (and therefore need replacement), and partly because, unlike a pocket watch that was handed down from generation to generations, wristwatches would be fashionable items that would be personable to their wearer, who would also want to have two or three to go with different outfits. Wilsdorf was not really interested in watches from a technical point of view, he was thinking like a marketing person who wanted to generate maximum sales revenue.

In 1902 while in La Chaux de Fonds, Wilsdorf had become acquainted with the watchmaking company Aegler in Biel / Bienne, who produced a small lever escapement movement with a reputation for precise time keeping and good availability of spare parts due to the modern precision production methods, making extensive use of machinery and gauges so that parts were interchangeable.

In 1905, soon after founding his firm in London, Wilsdorf went to Bienne to see Hermann Aegler and placed the largest order for wristwatches ever seen at that time. Wilsdorf says that the first wristwatches produced under this arrangement were for men's and ladies' wear in silver cases with leather straps, and that their immediate success after the autumn launch prompted him to widen the range and introduce a selection of designs in gold cases. Evidently he got his marketing right, the success was not due to a change in fashion; ladies had been wearing fashionable wristwatches like this for nearly twenty years, since the late 1880s.

Britannic Bracelet. Thanks to Click image to enlarge.

In the Vade Mecum Wilsdorf says ‘Next came the idea of expanding bracelets, which an important jewellery firm invented and launched in about 1906. This too won the approval of our British clientele ... [and] became increasingly popular throughout the Empire.’

The important jewellery firm was Edwin Harrop, who called the expanding bracelet they invented the ‘Britannic’ as shown in the advertisement reproduced here. Edwin Harrop was granted patent No. 24396/06 in 1907 for this design, which became extremely popular.

Wilsdorf rode the success of the Britannic bracelet, remarking that ‘... both a new fashion and a great commercial success sprang from an apparently foolhardy idea. Soon we were placing orders for tens of thousands of pieces ...’ So the early success of Rolex was, in part at least, due to Harrop's Britannic bracelet.

Wilsdorf doesn't say it in the Vade Mecum, but these expanding bracelets were for ladies' wristwatches. An attempt to introduce a similar expanding bracelet branded ‘Army’ during the Great War, emphasising the benefits of a metal bracelet over leather in wet and muddy conditions, fell upon stony ground because of its effeminate appearance, despite the branding.

Very few, if any, of these early wristwatches would have been sold to men, despite what Wilsdorf says. Before the Great War, wristwatches were very much considered a woman's item and men regarded them, like bracelets, as effeminate. An exception to this were military men who did buy wristwatches, but there is little evidence that Wilsdorf was involved in that area or realised that this small, specialised, demand existed.

The Britannic bracelet was guaranteed for five years, and tested in public demonstrations over 110,000 cycles. But they don't last forever, especially in everyday use, and many watches from the pre-war period have had their Britannic bracelets replaced. The lugs that attach the bracelet to the case are very narrow and won't take a leather strap, but they can be adapted for a leather strap by fitting Loop Ends.

Creation of the Rolex brand

In 1907 Hans Wilsdorf opened an office in La Chaux-de-Fonds for marketing purposes. Wishing to create his own brand he started using this Swiss office to register brand names in Switzerland. The first he name he chose to register was "Lusitania", on 1 November 1907. Lusitania was an ocean liner launched by the British Cunard Line in 1906; she was the biggest, fastest and most luxurious liner in the world at the time. In 1915 Lusitania was torpedoed and sunk by a German U-boat, an event that brought America into the Great War on the side of the Allies, but by then Wilsdorf had long since lost interest in the name.

Rolex Registration
First registration of the Rolex name in 1908

In 1908 Wilsdorf coined the name Rolex. Some have speculated that this had some complicated origin such as being derived from hoROLogie EXcellence, but in the Vade Mecum Wilsdorf says that Rolex was chosen because it was a short yet significant word, not cumbersome on the dial (thus leaving room enough for the inscription of the English trader's name) and, above all, a word easy to memorise. It has a pleasant sound and its pronunciation remains unvaried in whatever European language it is spoken. He doesn't reveal where the name came from, so we shall probably never know for sure, but it sounds like he simply made it up. His description of the way the word is short, easy to remember and pronounce echoes the words of George Eastman, who registered the trademark Kodak on 4 September 1888. Eastman said his criteria for creating the name were that it should be short, one cannot mispronounce it, and it could not resemble anything or be associated with anything but Kodak. I am sure Wilsdorf had the same considerations in mind when he devised the name Rolex.

Wilsdorf registered Rolex as a brand name in La Chaux-de-Fonds on 2 July 1908 as shown in the registration details reproduced here. This shows that Rolex is a trademark of Wilsdorf and Davis, manufacturers of watches, parts of watches and cases. Wilsdorf requested Aegler use the new trademark on all of his watches. Aegler wanted their own name to appear on the watches they manufactured, but reluctantly agreed to Wilsdorf's request. Wilsdorf wanted to create a brand that would distinguish his product from other watches, which may even have contained the same parts - Aegler was not an exclusive supplier to Wilsdorf at that time, also supplying movements to Gruen in America and others.

The Rolex Watch Company Limited was registered in London on 15 November 1915 under the Companies Acts 1908 and 1913. Today The Rolex Watch Company Limited is a wholly-owned subsidiary of Rolex Holdings SA, a company incorporated in Switzerland, and operates as part of the group's distribution and watch servicing operations. The company's principal activity is the sale of Rolex products to the watch industry in the UK and Ireland.

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Rolex in North America

Wilsdorf & Davis and Rolex started off as an English company headquartered in London. As the business expanded Wilsdorf naturally started looking to export watches to other countries. Until the Great War all Rolex watches were first imported to Britain from Switzerland and inspected in London, a practice that had been started in the eighteenth century by London retailers such as J W Benson who wished to overcome customers resistance to paying a lot of money for a Swiss watch. During the War, high import duties forced Wilsdorf to set up a Swiss office to conduct the inspection and send watches to other countries without passing through England.

Canadian A. W. C. Co. "Empress" case
Image courtesy of and © John B., 2016.

Exports of Rolex watches to other countries were successful and Wilsdorf & Davis's overseas business thrived, apart from in the United States. Rolex Rebberg watch movements were supplied by Aegler, who also supplied the company of the brothers Frederick and George Gruen in the USA. Wilsdorf and the Gruen brothers were shareholders in Aegler and had seats on the board, which resulted in the agreement that Rolex watches with Aegler movements would be sold throughout Europe, Asia and the British Empire, which included Australia and Canada, whereas Gruen would sell watches with Aegler movements in the USA only.

The image here of the inside case back of a watch with a Rolex branded Aegler Rebberg movement shows trademarks of the American Watch Case Co. of Toronto, Canada. It's a gold filled "Empress" grade case, the "10 years" is how long the plate is guaranteed to last in normal use before it wears through. The Rebberg movement would have been shipped out to Canada as a bare movement and cased there. Gold filled cases are not hallmarked so unfortunately this case can't be dated from a hallmark, but the watch appears to be from around the time of the Great War. During the War Wilsdorf had gold cases made in England, see and my immediate thought is that this case was made in Canada for similar reasons, import duties during the Great War. It is currently in England, perhaps it was brought to Europe by a Canadian soldier during the Great War and sold, swapped or lost.

Wilsdorf made a couple of half-hearted attempts to enter the US market while the agreement with Gruen was in force by selling watches with non-Aegler movements. The first was a watch with a movement from the Fontainemelon factory that was sold through Abercrombie and Fitch, a high-end retailer of sportsman's equipment and clothing. This did not work out well, the watch was not heavily advertised and had a cheap, chrome plated base metal, version of the Oyster case. Wilsdorf would not allow the name Rolex to be used on watches that didn't have Aegler movements so it was branded "Abercrombie and Fitch Seafarer", not to be confused by a later watch with the same name made for Abercrombie and Fitch by Heuer. It appears that Wilsdorf's watch didn't appeal to Abercrombie and Fitch's wealthy customers and the venture flopped.

Some time later Wilsdorf was approached by Zell Brothers, jewellers headquartered in Seattle who had a chain of jewellery stores in the North West of the USA and Canada. Zell had been selling Rolex watches very well in Canada, particularly in Vancouver which is not far from Seattle just across the US/Canadian border. The Zell brothers asked to be the exclusive importer for Rolex in the North West of the USA and Wilsdorf agreed. Again, because of the agreement with Gruen, any watches that Zell sold in the USA could not have Aegler movements. Again Wilsdorf would not allow the name Rolex to be used on watches that didn't have Aegler movements so the watches sold by Zell in the USA were branded "Turtle Timer", not exactly an inspired choice. Although the watches were better made with stainless steel case and Zell was more successful than the Abercrombie and Fitch venture, this was not a breakthrough into the US market for the Rolex brand.

In the 1930s Gruen stopped buying movements from Aegler and sold their shares in Aegler back to the family. Wilsdorf was finally free to introduce the name Rolex and watches with Aegler movements to the US market.

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Sponsor's Marks and Trademarks

Various marks appear on Rolex cases and movements. By tracking the evolution of these marks we can sometimes learn a bit more about the date of a watch. The earliest of these marks is the W&D mark in an oval shield with points top and bottom. This was first used as a sponsor's mark on gold and silver cases. From 1 June 1907 all gold and silver watch cases imported into Britain had to be assayed and hallmarked in a British assay office, and it was necessary for Wilsdorf and Davis to enter their details and a punch mark with the assay offices that they wished to use. This mark is also sometimes seen on watch movements. It seems likely that having created a unique mark for hallmarking purposes, Wilsdorf decided that it would also be used it to identify movements, strengthening the W&D brand identity.

The W&D sponsor's mark was superseded some time in the 1920s by "R.W.C.Ltd." The reason is not known, it perhaps indicates a more mature company stepping away from referencing the founder's names, and it also ties in with Wilsdorf's desire to promote the Rolex brand name. The R.W.C.Ltd. mark also seems to have been first used as a sponsor's mark for British hallmarking purposes, but then more widely used to promote brand identity.

W&D sponsor's mark

Wilsdorf & Davis W&D Sponsor's Mark

Until 1907 Wilsdorf & Davis imported gold and silver watches with Swiss hallmarks in their cases and under British law didn't require them to do any more. British law changed in 1907 and from 1 June 1907 all imported gold and silver watch cases were required to be assayed and hallmarked at a British assay office. Before items could be sent to an assay office for hallmarking it was necessary for a sponsor's mark to be registered. The sponsor is the person repsonsible for the item, who may not be its maker.

The sponsor's details to be registered with the assay office include a UK address and the sponsor's mark made by a punch used to identify each item that was sent in. This is the reason for the registration of the W&D sponsor's mark. The mark shown here with the initials W&D within a shield with round ends and points top and bottom was first registered at the London Assay Office on 25 June 1907. Wilsdorf and Davis were recorded in the register as importers of gold and silver wares. A second punch with the same mark was registered on 13 August 1907.

W&D on a Rebberg movement

Before watch cases could be sent to the assay office for hallmarking, the movements had to be removed and the empty cases stamped with the sponsor's mark by a registered punch. The registration of two punches on dates so close together indicates that the second punch was required to keep up with the volume of work rather than replacing a worn out punch, so Wilsdorf & Davis must have had at least two men working full time punching cases that were to be sent for hallmarking, and quite likely other workmen taking the movements out of the cases, and later putting them back into their cases after hallmarking.

The W&D mark was also entered at the Chester Assay Office on 6 April 1912. Two more punches with the same W&D mark were entered at the London Assay Office on 25 April 1915 and 25 August 1919. The same mark W&D mark was entered at the Glasgow Assay Office, but unfortunately the date is not found in the surviving records.

The following information is gleaned from Culme John Culme "The Directory of Gold and Silversmiths, Jewellers and Allied Traders, 1838-1914: From the London Assay Office Registers" Publication Date: 15 Oct 1987 | ISBN-10: 0907462464 | ISBN-13: 978-0907462460 Two volumes; the first with 4,000 biographies, the second with photographs of 15,000 marks taken directly from the London Assay Office Registers at Goldsmiths' Hall. . The partners in Wilsdorf & Davis were Hans Wilsdorf and Alfred James Davis. The address recorded at the registration of their punches was 83 Hatton Garden, later recorded on 1 November 1907 as moving to 85 Hatton Garden, EC1, then between 17 August 1912 and 25 August 1919 they are recorded at Stevenage House, 40-44 Holborn Viaduct, EC, where they are listed in 1913 as watch manufacturers and importers (TA: 'Wilsdorfs').

Wilsdorf & Davis are also recorded on 8 April 1915 at 15 Northampton Street, Birmingham, and also 3 Ruelle de la Fabrique, Bienne, Switzerland. They are recorded 25 August 1919 as having an office at 61 Rue Elfenau Gare, Bienne, Switzerland, in addition to their London office, and also as representatives of the Rolex Watch Co. Ltd. whose chairman was Hermann Aegler with Hans Wilsdorf and Alfred James Davis as directors and Harry Sedgley as secretary.

Image by permission ©

R.W.C. Ltd.

Sometime after 1920 the W&D sponsor's mark began to be replaced by the mark "R.W.C.Ltd" in an oval shield, all incuse, as shown in the picture here. This photograph is of a Rolex Oyster case.

The marks immediately below the R.W.C.Ltd are Glasgow Assay Office import hallmarks for 9 carat gold. Reading from left to right they are a 9 on its side and ⋅375, the standard mark for 9 carat gold, two prone capital "F"s facing each other, the mark the Glasgow Assay Office used on imported items, and the date letter "e" for the year from July 1927 to June 1928.

The mark "R.W.C.Ltd" in an oval shield was entered as a sponsor's mark at the London Assay Office at Goldsmiths' Hall on 11 September 1923. It was also entered at the Glasgow Assay Office, although the date of its entry at Glasgow is not recorded. The earliest Glasgow hallmark that I have seen in conjunction with the R.W.C.Ltd. mark has the date letter "a" for July 1923 to June 1924, so the Glasgow registration was most likely also entered in 1923 at around the same time as in London.

There is more about these two sponsor's marks on my page about Sponsor's marks.

British and Irish hallmarks

Before 1922 all of Ireland was part of the United Kingdom, and hallmarks struck in any UK assay office were valid throughout the realm. In 1922 the Irish Free State separated from the United Kingdom and formed the republic of Ireland. As a result of this separation, Irish hallmarks were not accepted in the UK after 1923, and UK hallmarks were not accepted in Ireland after 1927. Because of this, watches imported into Britain and hallmarked in Britain, if sent to Ireland, were then also assayed and hallmarked in Dublin. This could of course happen with any British assay office mark, but Glasgow Assay Office hallmarks are the ones most commonly seen alongside Dublin hallmarks. This seems to have happened more with Rolex watches than any other, I don't know why. An example of a Rolex case marked this way can be seen at Rolex case with Glasgow and Dublin marks.

Crown or Coronet

Rolex Coronet

Kathleen Pritchard says that the Rolex crown or coronet symbol with its five spikes tipped with balls or spheres was first used in an advertising campaign in 1925 and was registered later that year.

Rolex SAR

Rolex SAR

The mark shown here of the letters "SAR" under a crown or coronet is sometimes seen in the case backs of Rolex watches. This mark doesn't seem to be recorded anywhere, but I suspect that it stands for "Société Anonyme Rolex". That would indicate the existence of a Swiss limited liability company or Société Anonyme (S.A.), but I haven't yet discovered the date of creation of that company.

The legend "25 World's Records" was first used in circa 1931/32 (see below for more World's Records dates).

The crown or coronet symbol above the SAR has seven spikes tipped with balls or spheres, which is two more than usually seen on the Rolex crown. I wonder why?

World's Records

Rolex case backs sometimes have a reference to a certain number of "World's Records". It is not known what records these claims refer to, but the number of records claimed increases in steps from seven to twenty and then twenty five. Knowing when the increment occurred can help to identify when a watch was made.

By studying dozens of case backs with British hallmarks, and therefore date letters that pin down the date of hallmarking to a two year period, I have identified the approximate dates when the increments of World's Records occurred. British assay offices changed their date letter punches when new wardens were elected, part way through the calendar year. At the London Assay Office this was at the end of May, for most other offices it was the beginning of July.

Parachute RM

Parachute RM
Parachute RM Trademark 1934
Image courtesy of and © John Goldberger
Robert Meylan registration 1928
Robert Meylan Registration 1928

The "Parachute RM" trademark was registered in 1934 by Robert Meylan, a Geneva based company making watch cases. They were first registered in 1928, the registration details shown here say that they specifically make wristwatch cases — boîtes de montres-bracelets. The registration also gives Ponts-de-Martel and le Chenit as if they also had operations there; I don't know what the "R.-Numa M." means. They were granted three Swiss patents for watch cases in 1932/33. There is very little recorded about the company.

One very notable thing is that Robert Meylan are not on the 1934 list of registered Swiss watch case makers Poinçons de Maître, the implication being that they didn't make watch cases of precious metals, i.e. that they only made watch cases in steel or nickel. The image of the RM parachute mark reproduced here was sent to me by John Goldberger, author of a number of books about Rolex and other brands. The mark is in the back of a case marked "Oyster Watch Co. Geneva - Swiss". It has no hallmarks of any kind and appears to be steel.

I find this rather curious. The company was first registered in 1928 when gold and silver cases were still predominant, stainless steel cases didn't come to the fore until the 1930s. Do let me know if you find a case with this mark in gold, or in any watches other than Rolex.

Thanks to John Goldberger I have now seen a Rolex case made by Robert Meylan in .925 silver. This case doesn't carry a Poinçon de Maître. Although the system of poinçons de maître included provision for marking silver cases, very few have such marks. It was evidently only gold and platinum cases that the authorities were particularly keen to see marked.

Snowite Cases

Oyster Watch Co. Case Back: Click to enlarge.
Snowite 20 years
Image courtesy of and © Heritage Auctions

Some Rolex Watch Co. watch cases, most them not branded as Rolex watches but with other brands such as Unicorn and Wintex, are stamped in the case back "Snowite". Some are stamped "Snowite Guaranteed to Stay Blue White". The name Snowite was registered by Hans Wilsdorf in Switzerland in February 1927.

Snowite was chrome plate over a base metal. Some people think the base metal was nickel but James Dowling told me that it was a zinc compound like Zamak or Mazak. These alloys can be formed into shapes by high pressure die casting, where the molten metal is injected into a steel mould and allowed to solidify under pressure before it is ejected. This allows a lot of identical shaped components to be produced very quickly and cheaply. The zinc alloys have a dull grey appearance and are not corrosion resistant so they are usually plated, most often with chromium.

The first commercial process for chromium plating was developed in 1924 in America and the 1927 registration of Snowite means that Rolex were one of the first companies to use it on watch cases. The 1920s economic depression that resulted in the Wall Street crash of 1929 meant that manufacturers were looking for cheaper but still eye catching alternatives to gold and silver. Stainless steel was introduced in the 1930s for the same reason

The case back in the picture here says "Snowite: Guaranteed to stay pure white for 20 years". This refers to the thickness of the plating, it won't wear through and show the base metal for at least twenty years in "normal use".

The second image shows the case back of an ‘Oyster Watch Co.’ watch made from the injection moulding zinc alloy. This is a very poor quality material and, although it is chrome plated, the back very heavily pitted on the outside. I don't have the other parts of the case so I don't know how well they survived, the case back was against the wrist and some people's perspiration can cause corrosion damage, even on some grades of stainless steel. This case is particularly bad.

Later watches with Snowite front parts to their cases have stainless steel backs to avoid this. However, even the front parts of Snowite cases can suffer from heavy corrosion. It is not a good material.

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CH196706 Patent Superbalance

Some Rolex (Aegler) watch movements have the words "Patented Superbalance" on the ratchet wheel. This refers to the type of balance shown in the image here, reproduced from Swiss patent CH196706. The patent was granted to Manufacture des Montres Rolex, Aegler Société Anonyme, Bienne (Suisse).

It is sometimes said that the purpose of recessing the screws into the rim was to make the balance more streamlined, thus reducing air resistance. This was not in fact the principal objective of the design, although one of the six claims does say that the walls of the recesses are convex in order that their shape is advantageous from an aéro-dynamique point of view. Having worked in a fluid flow laboratory I can say that the effect of this would be, at best, negligible, and that by introducing the extra turbulence-inducing walls of the recesses it might actually increase air resistance. It's a moot point. However, the main text also makes it clear that this was not the main purpose of the design.

The principal objective of the Superbalance was to make maximum use of the space available for the balance, especially within a small calibre wristwatch movement. By recessing the screws into the rim of the balance, or in effect growing the balance outwards so that it extended past the base of the screws, the radius of gyration of the balance could be made greater within a certain space than that of a balance with a plain rim and screws sticking out from that.

Inertia is the resistance of a body to any change in its speed or direction of motion. The moment of inertia, also called the rotational inertia or angular mass, determines the torque needed for angular acceleration about a rotational axis. In a watch oscillator comprised of a balance and spring, the moment of inertia plays an important role in determining the period or frequency of oscillation. The period \(T\) of oscillation of a sprung balance is given by the equation:

\[ T=2\pi\sqrt{\frac{I}{S}} \]

where \(I\) is the ‘moment of inertia’ of the balance, and \(S\) the turning force produced by the balance spring.

The moment of inertia is determined by the product of the effective rotating mass of the balance ‘m’, which as an approximation can be thought of as the mass of the rim, and the square of its radius of gyration ‘k’, which is the radial location of the effective mass and is approximately the radius of the rim as shown in red on the figure. The moment of inertia is given by:

\[ I = mk^2 \]

The Superbalance, with a radius of gyration greater than that of a plain balance which occupied the same space, could be made to have either a higher moment of inertia than a plain balance of the same mass, which would require a stronger balance spring, or a lower mass whilst maintaining the same moment of inertia. Reducing the mass of a balance whilst maintaining the same moment of inertia is beneficial because it keeps its natural frequency the same whilst reducing the loads on the balance staff pivots, which reduces friction.

The application for the patent was submitted in August 1936, but the words "Patented Superbalance" would only be used after the patent was actually granted, which was in March 1938.

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Aegler is very important name in the history of Rolex.

The Aegler watchmaking company was established in Biel / Bienne in 1878 by Jean Aegler. Biel / Bienne is on the language boundary between the French and German speaking parts of Switzerland, hence the dual name for the town. Biel is German, Bienne its French counterpart. Because this is a bit of a mouthful and I am discussing Aegler in the context of Rolex, which is headquartered in Geneva in the French speaking part of Switzerland, I shall refer to the town as simply Bienne.

Aegler Factory 1881
Aegler First Factory. Click to enlarge.

Jean Aegler was born on 25 January 1850 in Krattigen, a small Swiss village about 90 kilometres south east of Bienne situated on a hill overlooking Lake Thun. He was the son of Johannes Aegler and Susanna nee Isler. Jean Aegler trained as a watchmaker before founding his own company. Johannes Aegler is recorded as being an "instructeur, huissier et facteur", so Jean could perhaps have studied under him, but it seems more likely that he was sent to Bienne for his apprenticeship. Jean Aegler married Anna Maria Ramser on 26 July 1873 in La Neuveville. He died on 2 August 1891 in Bienne at the young age of only 41 years.

In 1881 Jean Aegler acquired a workshop in the Rebberg district of Bienne on La Haute-Route, overlooking the city centre. The history of this factory is virtually unknown. The image here shows the original factory block from 1881, although this image was made after Jean Aegler had died in 1891 and his widow had taken over running the company. At the time in Switzerland, privately owned companies had to be named after the person or persons in charge, so as soon as one person or partner died or left the company, a name change had to follow. In this case the name was changed Veuve Jean Aegler (widow of Jean Aegler), often abbreviated to Vve. Jean Aegler as in the image. This device maintained continuity of the Jean Aegler name whilst complying with Swiss company law.

A couple of things in the advert are worth noting. It says that the company specialised in "Damen Uhren" or "Montres Pour Dames", that is ladies' watches. At this time, ladies wristwatches usually had small movements with cylinder escapements, but Aegler specialised in lever movements, so these were small pocket watches or fob watches, worn pinned to the outside of clothing on a fob or chatelaine. The movments of such watches were an ideal size for later use in men's wristwatches. The second thing of note is the Swiss Federal cross with SP and 243. This is a reference to Swiss patent No. 243 for a keyless stem winding and setting mechanism, which is discussed below.

A press release announcing the new Rolex factory in Bienne in 2012 said that the Aegler factory began to produce its own ébauches between 1890 and 1895. This is not correct. The advert reproduced here says that the watchmaking factory Jean Aegler of Rebberg, Bienne, makes a speciality of stem wound watches (remontoirs au pendant) and has a new system of setting the time, the most advanced that exists (le plus perfectionné qui existe). The stem wind mechanism was the subject of a Swiss patent No. 243 mentioned at the bottom of the advert. This patent was granted to Jean Aegler in November 1888, so it would appear that the Aegler factory was making complete movements by 1888 or 1889.

Aegler advert from 1890
Aegler Advert

Jean Aegler had probably not started out making complete ébauches in 1881, because it would have taken him time to accumulate the capital to buy the necessary machinery, work out the designs for the movements, recruit and train workers etc., so he most likely started out either making or finishing component parts for other companies, gradually building up his factory and workforce until he had the capability to produce the complete movements.

In 1886 Jean Aegler was present at a meeting of horological workers of Bienne and the surrounding area at which the formation of a syndicate to control prices and working conditions in the industry was agreed. Aegler was named in a list of workers who specialised in "small pieces". In view of Aegler's later reputation for making small watches it is likely that this refers to small movements rather than small component parts. This view is supported by a letter of 1888 announcing the formation of of the "Syndicat de fabricants d'horlogerie". Jean Aegler was one of the signatories to the letter as a secretary to the syndicate.

Swiss patent No. 243

On 15 November 1888 Jean Aegler was granted Swiss patent No. 243 for a Mécanisme de mise à l'heure par la couronne; a mechanism for setting the hands to the correct time using the crown. This patent is referenced at the bottom of the advert: "Brevet pris on Suisse sous No. 243" — Swiss patent is taken under No. 243.

The mechanism, or "keyless work", was a variation on the sliding sleeve mechanism invented by Adrien Philippe in 1845. In common with many patents taken out on stem winding and setting mechanisms based on Philippe's invention, Aegler's patent concerned the arrangement of levers that moved the sliding pinion between the winding and setting positions.

Aegler patent 243
Figure from Aegler patent 243 of 1888

In the figure from the patent you can see the Philippe pinions clearly, the crown or winding pinion is labelled C, the sliding pinion B. Pulling upwards on the stem causes lever F to press down on lever A, which is engaged in the slot around the sliding pinion. Lever A rotates around its securing screw as shown by the dotted lines and the sliding pinion is pressed downwards into the hand setting position. When the stem is pushed down, the spring a pushes the lever A back, which returns the sliding pinion to the winding position.

When Jean Aegler died 1891 his widow Anna Maria took over the business, which was renamed Veuve Jean Aegler (widow of Jean Aegler), often abbreviated to Vve. Jean Aegler.

An additional patent No. 243/104, an extension to No. 243, was granted to Madame Veuve Jean Aegler in December 1891. This patent, with the same title as the original 243, was for an improvement to the mechanism of levers that moved the sliding pinion between the winding and setting positions. The difference is very small, only slight changes to the shapes of the levers. Today this would not be accepted as a new "invention". Swiss patent law had only been introduced in 1888 and in the first years many designs that would not have been patentable in Britain or the USA were granted patents in Switzerland. Swiss manufacturers evidently saw it as a good way to both protect their designs and gain a bit of status by stamping patent numbers, or references to patents with the word Brevet or the symbol of the Swiss Federal cross Swiss Federal Cross, on their products.

By 1902 the business under the direction of Hermann and Hans Aegler, the sons of Jean and Anna Maria, was manufacturing small ébauches with lever escapements. The business gained a reputation for the mechanised manufacture at reasonable prices of good quality lever movements on the gauged and interchangeable system, which made it easier to fit replacement parts if required. The name "Rebberg", after the Rebberg part of Bienne where the factory was located, was registered in 1902 as a trade mark.

In April 1902 Swiss patent No. 23382 was granted to "Witwe Jean Aegler" for a "Taschenuhrgehause", a pocket watch case. The language used is German, Witwe means widow in German. The case design extends the bezel and back over the middle part of the case, also called the case band, so that the bezel and back meet in a single joint and the middle part of the case is umschließen und nach außen unsichtbar machen — enclosed and invisible to the outside.

Aegler partnership
Transfer of Patents to New Partnership

In 1905 Hans Wilsdorf of Wilsdorf & Davis in London placed a large order for wristwatches with Aegler. In the Rolex Jubilee Vade Mecum, Wilsdorf says that the first line of wristwatches that he placed on the market were silver watches with leather straps for men's and ladies' wear, and that their success was immediate so that the range had to be widened, in particular to watches with gold cases. In view of the prevailing fashions of 1905 the success must have been with the ladies' models. This view is implicitly confirmed by Wilsdorf himself, who says that an expanding metal bracelet was launched in 1906 and our little gold watch became increasingly popular throughout the empire. A little gold watch on an expanding metal bracelet sounds to me like a ladies' wristwatch and not the sort of thing that an Edwardian gentleman would be seen dead wearing.

In July 1906 the trademarks and patents of Veuve Jean Aegler were transferred to a new company, a "nom-collectif" or partnership "Les fils de Jean Aegler, fabrique Rebberg" (The sons of Jean Aegler, makers of Rebberg). Presumably Madam Aegler had decided to retire.

When Wilsdorf coined the name Rolex in 1908 he decided that he wanted to have only this name on the watches supplied to Wilsdorf & Davis by Aegler. Aegler felt that as the maker their name should be on the watches, but in the end Wilsdorf got his wish.

In 1910 an 11 ligne lever escapement Rebberg watch was awarded a first class certificate at the Bienne rating office. This is described in the Rolex Jubilee Vade Mecum as the first Rolex wrist-watch chronometer.

Rebberg first class certificate
Aegler advert from 1910 mentioning first class certificate for 11 ligne Rebberg movement with lever escapement

The Aegler advert here from March 1910 celebrates this feat but doesn't mention Wilsdorf or Rolex. This is often reported to be the first time a wristwatch had obtained a chronometer certificate but the advert doesn't mention this, which seems a curious omission and missed advertising opportunity.

In 1913 Aegler registered Rolex as a trademark for the manufacture of watches and watch parts. From this point on the history of Wilsdorf & Davis, Aegler and Rolex becomes virtually impossible to untangle from information publicly available, and the modern Rolex foundation never divulges any of its history.

What appears to have happened is this. Wilsdorf & Davis owned the name Rolex, which Hans Wilsdorf was very proud of. He wanted it to appear only on the best watches supplied to him, the ones made by Aegler. Accordingly he kept pressing Aegler to increase the use of the name Rolex, and as Wilsdorf & Davis were one of Aegler's largest customers they went along with this, describing themselves in adverts as both "Manufacture d'Horlogerie Rebberg" and "Rolex Watch Co.". The name Rolex was used by liberally by both Aegler and Wilsdorf & Davis in ways that can be very confusing. The single word "Rolex" was used as a brand name on the best watches produced by Aegler for Wilsdorf & Davis, but it was never the name of an actual company. Conversely, the name "Rolex Watch Co." on a watch does not mean that it is a "Rolex" watch, only that it was a product sold by the Rolex Watch Co.

Is this all a semantic exercise in splitting hairs? Maybe. But today some people advertise Rolex Watch Co. watches as if they are Rolex watches, which can trap the unwary into paying too much for a watch that more seasoned collectors do not regard as a Rolex watch, so it is good to be aware of the arguments. And caveat emptor.

Aegler name change 1912
Aegler partnership name change 1912 Aegler S.A. 1913
Aegler S.A. registration 1913

In November 1912 the registered name of the Aegler company was changed to Les fils de Jean Aegler, Fabrique de montres Rebberg, Final & Rolex (The sons of Jean Aegler, manufacturers of Rebberg, Final and Rolex watches). The reason for this change evidently defeated the composer of the announcement shown here, which says "The partnership known collectively as .... is modified for the reason as follows:" and then simply recites the new name without trying to give a reason. In Switzerland the names of at least one of the active partners had to appear in the business name of the company, so this probably signifies the retirement of Madam Aegler.

This mouthful of a company name didn't last long though, because as the next notice shows a new, limited, company was registered on 26 September 1913, "Aegler S.A.". Notice that the composition of the company changes from a "nom collectif", a partnership, to an S.A. or "Société Anonyme", a joint-stock or limited company, a company with shareholders whose liability is limited to the amount they have invested.

The notice states that the new company Aegler S.A. was formed for the purpose of the acquisition and continuation of the previous partnerships Les fils de Jean Aegler, Jean Aegler and Witwe Jean Aegler. Aegler S.A. became the legally registered name of the company and after this date any other names or additional terms used by the company such as the addition of "Manufacture des Montres Rolex" after the registered name was a trading name with no legal significance.

In Swiss/French the word for shares in a company is "actions" so a société par actions is a joint stock company with shareholders who appoint a board of directors to run the company. Note that shares in a such a company do not have to be offered to the public, they can be held privately by the people who founded the company or sold at their discretion to raise capital. A joint stock company is a legal entity and its finances are separate from the personal finances of the shareholders, unlike a nom-collectif or partnership, where the partners are jointly and severally liable for any debts incurred by the partnership. Limited liability and joint stock companies are formed when the business is getting bigger and if unseen problems arose the consequences could be catastrophic for the individual partners, so the formation in 1913 of Aegler S.A. was a sign that the business was booming.

Aegler Xi trademark 1913
Aegler S.A. Trademark Xi 1913

Aegler S.A. registered the trademark of the Greek letter Xi over three lines within an oval as shown here. A date of 7 October 1913 is recorded for this registration, but I have seen a case with London Assay Office sterling silver import hallmarks for 1909 to 1910 with the same mark, so it was in use earlier than 1913. The letters Xi within an oval, and separately three lines within an oval, had been registered as trademarks in October 1900 by the company Vve. Jean Aegler. The new trademark was a combination of the two separate marks.The Greek letter ‘Xi’, properly rendered Ξ is the 14th letter of the Greek alphabet. If it hadn't been for the domination of Aegler by their principal customers Rolex and Gruen, perhaps Ξ would be as well known today as is Ω.

Wilsdorf opened an office in Bienne in 1916 to be near to Aegler, which was becoming increasingly important to his business. This increased further in importance when high import tariffs were imposed by the British government during the Great War (1914-1918). Previously all watches sold by Wilsdorf & Davis had been sent to London for inspection before being sent on to retailers both within Britain and the rest of the world. The high import tariffs meant that this added extra cost to watches that were destined for markets outside Britain so the Bienne office took over the duty of inspecting these watches and dispatching them direct to their destination.

This was the start of a move headquarters of Wilsdorf & Davis and Rolex from London to Switzerland. If it hadn't been for the Great War and British import duties, Rolex might still be a British company.

Aegler SA 1929
Aegler SA 1929, Manufacture of Rolex & Gruen Watches.

In 1919 a new company was incorporated in Geneva by Wilsdorf & Davis as Montres Rolex SA. Its manufactory was listed as "Manufacture des Montres Rolex, Aegler S.A." but the two companies, Aegler S.A. Bienne and Montres Rolex S.A. Geneva, were legally separate entities. Aegler also had other customers, the largest of which was the US firm Gruen. The notice here from 1929 shows that Aegler Ltd. was the manufacturer of Rolex and Gruen Guild watches.

Over the next few years this remained the situation. Aegler supplied Rolex branded watches to Montres Rolex S.A. who organised their distribution to approved outlets, and advertising and marketing. Aegler also supplied watches to Gruen, who sold them in the USA, and to others. Montres Rolex S.A. and Gruen were Aegler's biggest customers and they had a mutually beneficial arrangement where Gruen would only sell watches in the USA and Montres Rolex sold watches to the rest of the world. As the USA was the wealthiest consumer market in the world at the time this was not so unbalanced as it sounds.

Aegler Factory 1920
Aegler Factory 1920. Click to enlarge.

The image here shows a drawing of the Aegler factory in 1920. If you compare it to the drawing of the first factory, you can see that that is now the smallest block at the right hand end. The three main parts are dated, the oldest factory carries the date 1881. The block next to it on the left is dated 1896 - 1912, the block nest to that 1914.

On the roof of the main blocks are two banners. The first says "Aegler S.A.", the second "Montre Rolex". When this image was reproduced in America, the "Montre Rolex" was altered to "Montre Gruen".

Montres Rolex and Gruen did not take all the watches that Aegler could make, so Aegler also continued to supply watches to other companies. At the same time, Wilsdorf was interested in making watches that could be sold at lower price points than the top line Rolex branded watches, so he bought in movements and watches from other manufacturers such as Fontainemelon and Valjoux to be used in watches carrying names such as Marconi, Unicorn and Tudor.

During the Great War Emile Borer, nephew and ultimately successor to Hermann Aegler, joined the Aegler factory personnel as an engineer. He soon became responsible for developing new technology and developed an automatic winding system that was patented by Aegler in 1931. Emile Borer was appointed as a director of Aegler in 1931 and subsequently became Chief Technical Director, and then in 1944 General Manager of Aegler S.A.

Business between Rolex and Aegler flourished until by 1920 Rolex was Aegler’s largest customer. The post war slump that culminated in the Wall Street Crash of 1929 and the ensuing Great Depression hit Montres Rolex's business hard, and Hermann Aegler invested in the survival of his largest customer by acquiring 6,960 shares of Montres Rolex S.A. and was appointed to the board. It is said that he was given these shares, but there must have been some sort of quid-pro-quo. As business recovered both Rolex and Gruen became large shareholders in Aegler.

The Aegler company adopted the trading name "Aegler, S.A., Fabrique des Montres Rolex & Gruen Guild A". Gruen and Montres Rolex adverts of the period show pictures of the Aegler factory with either Rolex or Gruen on the factory roof, implying that it was a Gruen or Rolex owned factory. As the Gruen adverts were for US display and Montres Rolex adverts for display outside the US this dichotomy was not obvious to consumers. Over the years various names were used to identify the Aegler factory more and more closely with Rolex, but these were just trading names. The legal entity that owned the factory was Aegler S.A., which was owned by the Aegler and Borer families.

Bloomberg overview
Bloomberg © 2016: Acquisition of Aegler by Rolex in 2004

In the 1930s Gruen and Montres Rolex S.A. sold their shares in Aegler S.A. back to the company, and Aegler S.A. sold its shares in Montres Rolex S.A. to Wilsdorf. In 1936 Gruen ceased purchasing watches from Aegler and Montres Rolex S.A. Geneva agreed to take up the entire production of the Aegler S.A. factory in Bienne, and the factory was renamed “Manufacture des Montres Rolex S.A.”, although it was now wholly owned again by the Aegler family.

In 1969 Harry Borer, son of Emile Borer, took over management of Aegler S.A. and oversaw the expansion of the company, with eventually seven new production buildings being built in the Champs-de-Boujean industrial area of Bienne.

This continued to be the situation until 31 December 2004. The company overview by Bloomberg reproduced here tells the story in a few words. The company now called Manufacture des Montres Rolex S.A. was incorporated in 1913. This is clearly the company that was incorporated in 1913 as Aegler S.A. The two companies remained separate until 2004 when Harry Borer sold Aegler S.A. to Montres Rolex S.A. and Rolex finally owned the Rolex movement factory. As the Bloomberg report shows, the manufacture in Bienne is still a separate company called Manufacture des Montres Rolex SA, a wholly owned subsidiary of the company now called simply Rolex SA.

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Rolex Aegler Rebberg Movements

Aegler Rebberg movement
Aegler Rebberg Movement marked Rolex on ratchet wheel: Click to enlarge.
Aegler Rebberg movement
Aegler Rebberg Movement Marked W&D: Click to enlarge.

Aegler manufactured movements in its ébauche factory in the Rebberg district of Bienne, and consequently Rebberg was a registered as a trade mark by Aegler. Early Aegler movements used in Rolex watches are often referred to as "Rebberg" movements because of this, even if they are not stamped with the Rebberg name. If they are stamped Rebberg, it is often on the bottom plate under the dial so not normally visible.

Aegler supplied Rebberg movements to Wilsdorf & Davis, and also to a lot of other companies. In fact it is most likely that Aegler supplied complete, cased, watches. Companies in London that Aegler supplied, such as the fledgling Wilsdorf & Davis, were simple import operations with no factory capability in England to put movements into cases and test the finished watches. All the silver cases that are seen with Rebberg movements, and gold cases until 1915, were made in Switzerland, so it is most likely that the movements were cased and the finished watches tested at the Aegler factory. You can read about the other companies that Aegler supplied on my page about Aegler.

The two images here show savonnette versions of these Rebberg movements with their characteristic single central bridge holding the pivots of all the train wheels; centre, third, fourth and escape wheel. The movement with the perlage decoration to the plates is 13 ligne, the one with the plain plates is slightly smaller and shows a slight variation in the shape of the central bridge, but is still unmistakably an Aegler Rebberg. They are both stem wound and set lever escapement movements with 15 jewel bearings, although Wilsdorf also imported lower grade 7 jewel versions. Savonnette movements were used in savonnette (hunter) pocket watches, and in Lépine (open face) wristwatches because they have the fourth wheel at 90 degrees from the stem. This allows the crown to be at three o'clock and the small seconds indication at six o'clock on the dial.

The smaller movement is from a watch with a Borgel screw case with London Assay Office import hallmarks for sterling silver dated 1910 to 1911. Both the case and the movement carry the W&D mark of Wilsdorf and Davis. On the case this is not unusual, a silver or gold case had to be punched with a sponsor's mark before it would be accepted for assay and hallmarking. But to find the same W&D mark on the movement is quite unusual.

The second movement dating from circa 1918 carries the single name "Rolex" so this is a Rolex watch, not just a watch that was sold by the Rolex Watch Company. But notice that the Rolex brand name is engraved on the ratchet wheel. This is an easy component to change, just a single screw holds it in place. This was most likely an idea of Aegler's to reduce the amount of stock they needed to hold. They could cheaply hold ratchet wheels engraved with Rolex or any other name, and then when an order came in they could simply take unbranded movements and change the ratchet wheels to one with the name given on the order. This was a more cash efficient system than tying up lots of movements with names engraved on their bridges which then could only be sold to that customer.

Wilsdorf would have wanted the Rolex name engraved on the bridge of of movement from the outset, but in the early days, before the 1920s, he was only one of many customers Aegler had and they could afford to refuse him. This is most likely the source of the story that Aegler at first refused to put the Rolex name onto their movements. They didn't want to engrave it onto the bridges because that stock could then only be sold to Rolex. But they put lots of different names on ratchet wheels, which could be easily exchanged, so it wasn't that they didn't want another company's name appearing on their movements at all, just not on the bridge where it was difficult to change or remove.

When Rolex became more important to Aegler as a customer they had to listen to him more seriously and the Rolex name got engraved on the bridge. The earliest watch that I have seen with Rolex engraved on the central bridge of the Aegler Rebberg movement had Glasgow Assay Office import hallmarks in the case back with the date letter "d" for the year 1926 to 1927.

Wilsdorf had the movements supplied by Aegler fitted into cases in Switzerland, or sometimes in England by the Birmingham case maker Dennison. In the beginning all watches imported by Wildorf and Davis were cased in Switzerland but during the Great War the British government imposed a high import duty on clocks and watches. This made it worthwhile to get gold cases made in Britain and Wilsdorf turned to Dennison for this. The economic incentive was not so great for silver cases because the case was a smaller proportion of the overall cost of the watch so they continued to be made in Switzerland.

Aaron Lufkin Dennison (1812-1895) had pioneered mass production watch making in the USA, but ran into technical and financial difficulties, eventually going into liquidation in a turbulent financial period in 1857. In 1871 Dennison moved to England and in 1874 set up the Dennison Watch Case Co. of Birmingham. Watch cases supplied to Wilsdorf & Davis were usually stamped "Dennison Watch Case Co." If they were silver, or more usually gold, the registered sponsor's mark for hallmarking was "ALD" for Aaron Lufkin Dennison.

Wilsdorf & Davis imported complete watches from Switzerland already cased in silver cases, and stamped these cases with their own sponsor's mark when they were sent to be hallmarked, and this was most likely true also for gold watches until the outbreak of the Great War in 1914 when high import taxes were levied on imported clocks and watches. For silver cased watches, where the case was perhaps only half the cost of the watch, it was not worth getting cases made in Britain, but it was better economically to have gold cases, which were a big part of the cost of a gold watch, made in Britain and then the movements put into them in the UK to avoid the import tax on the gold case.

There is a page about Dennison at Aaron Dennison and the Dennison Watch Case Co.

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Rolex on the Dial

Early Rolex watches, by which I mean before about 1926, are often clearly marked Rolex inside the case back and on the movement ratchet wheel, as well as carrying the W&D sponsor's mark if they are in gold or silver cases with British hallmarks. These watches usually do not have the Rolex name on the dial. This is because British retailers at that time did not allow the names of foreign watch manufacturers to appear on the faces of the watches they sold. If there was a name, it was the name of the British retailer. This was usually added in enamel paint, which is not as durable as the vitreous enamel of the dial and has often partially or fully worn off.

Occasionally one finds an early Rolex watch, or even a watch that is not a Rolex, with the name Rolex on the dial, and the question is asked; is this original? Not on Rolex watches sold in Britain, for the reason explained above, and especially not on non-Rolex watches, for obvious reasons. If a pre-1926 watch with British hallmarks showing that it was retailed in Britain has Rolex on the dial, then it was applied after it left the factory - and probably quite recently. Why is this? Basically the name has been added to increase the value of the watch. The full story is, of course, more complicated than this, so read on . . .

Wilsdorf began his business in London in 1905 as an importer, ordering watches from Swiss manufacturers and selling them to British retailers. Until 1 June 1907 these watches would have carried no signs that Wilsdorf had ever had anything to do with them. Gold and silver watches would have Swiss hallmarks inside the case back and "Swiss made" on the movement and dial. But from 1 June 1907 imported gold and silver watches were required to be assayed and hallmarked in a British assay office, so Wilsdorf had to enter his details and a sponsor's mark, the well known W&D in a shield with points top and bottom, at the London Assay Office at Goldsmiths' Hall. Imported gold and silver watches were stamped with this sponsor's mark before being sent for hallmarking. It might have been this development that eventually gave Wilsdorf the idea that he could put his own brand onto watches that he ordered from manufacturers in Switzerland.

This gives rise to another question that comes up quite often, is a watch that carries the W&D mark but no other marks actually an early Rolex? In my view the answer must be no. Wilsdorf was very proud of the brand name Rolex and only used it on watches that he was proud to put his name to. Watches sometimes turn up with the W&D mark that are not of the top grade, with unjewelled trains for instance. These are sometime thought to have forged W&D marks, but I think it is more likely that in the early days when Wilsdorf was getting the business off the ground he would import anything that he thought he could make a margin on, but he didn't give these the Rolex name.

Wilsdorf also created a lot of other brand names such as Unicorn, Marconi, RolCo and Tudor for lower price points, always keeping the name Rolex for the premium, top line, products. To begin with there was no secret that these were products of the Rolex Watch Company and were often marked as such, but Wilsdorf did not intend to call them "Rolex watches". It seems that initially Wilsdorf was happy if people got the impression that they were getting a Rolex watch at a lower price. But over time it was realised that this was not a good idea as it took sales away from the premium Rolex brand, and as people became more brand conscious it diluted the effects of expensive marketing that was aimed at building up the cachet of owning a Rolex, so gradually the Rolex name was disassociated from the other brands. But once an idea is planted it is very difficult to stamp it out, and today people often describe a watch with one of these other brands as a "Rolex watch". For more about these other brands see Rolex's Other Brands.

Silver Rolex Watch
My grandfather's 1918 silver Rolex wristwatch. No Rolex on the dial, and there never has been

In my view, unless a watch carries factory applied Rolex branding, then Wilsdorf wouldn't have regarded it as a Rolex, and neither should we. By factory applied Rolex branding I mean specifically the single word Rolex (Not "Rolex Watch Co.", "RWC" or any other variant) either stamped into the case back, engraved onto the ratchet wheel, or fired into the enamel of the dial.

Of course any of these can be faked, someone could get Rolex and W&D stamps made to mark case backs, could engrave Rolex onto a ratchet wheel, or take one from a scrap movement, and/or could paint Rolex onto the dial. I have even seen a Marvin watch that had been laser engraved with "Rolex" in the case back and on the movement, and had "Rolex" added to the dial with enamel paint. Needless to say, it had nothing to do with Rolex or the Rolex Watch Company.

Putting the name Rolex onto an enamel dial is the easiest to do, but also the easiest to detect, because with a touch of solvent the paint will dissolve. The same as happens to retailers names painted on to enamel dials. I am sure that when Wilsdorf started applying Rolex branding to watch dials, this would have been fired into the enamel and impossible to remove.

British Rolex Branding

So when did Wilsdorf start applying factory Rolex branding to watch dials? In the beginning, in common with almost all other watches sold in Britain at the time, the Rolex name was stamped or engraved on the case and movement only; the dial was left free for the retailer to apply their name. To start with Rolex was a new and unknown name whilst most of the stores they supplied had been in business for a long time. Naturally people would have more faith in a watch with the name of "Asprey" or "Harrods" on the dial, rather than the unknown Rolex. This might not have been the case for markets outside Britain, of which more below

Wilsdorf had great difficulty in getting British retailers to accept the name Rolex on the dial as he explains in the Vade Mecum Despite the qualities of [the Rolex] name, it took twenty years of hard work to make the idea acceptable in England. At first, I ventured to inscribe it on one watch in every six; then it appeared on two, and later three, in every six. This half victory was still unsatisfactory and we knew that it would take many more years to obtain the desired result. Tired of waiting, in 1925, I decided to launch the "Rolex" trade mark by means of an intensive advertising campaign. The policy entailed annual expenditure of more than £12,000 - not for one year alone, but for several in succession. One of the results thus obtained was that dealers agreed first that four, and later five, out of every six watches should bear the name of "Rolex". At last, in 1927, the waterproof "Rolex-Oyster" was launched and we were then in a position to announce definitely that in future not one of our watches would ever again leave our works without our name on the dial, inside the case and on the movement.

Note that Wilsdorf says that one of the reasons he liked the name Rolex was that it was not cumbersome on the dial (thus leaving room enough for the inscription of the English trader's name) (emphasis added) and that it took twenty years of hard work to make the idea acceptable in England (emphasis added). His initial idea was clearly that the name Rolex would be placed on the dial whilst still leaving room for the English retailers name, but the retailers were not amenable. Britain and the empire was an important market for Wilsdorf and Rolex, which may be why he concentrates on this point. But is is clear that had the English retailers not prevented him from putting Rolex on the dial he would have been at it like a shot.

Wilsdorf is rather vague about what date he means when he says At first, I ventured to inscribe it on one watch in every six; He says the struggle took twenty years, and that At last, in 1927, the waterproof "Rolex-Oyster" was launched and we were then in a position to announce definitely that in future not one of our watches would ever again leave our works without our name on the dial ... Twenty years before 1927 would be 1907, when Wilsdorf had only just thought of the name Rolex. The implication of this is that right from the start one in every six British imports, which can generally be distinguished because cases at the time were usually gold or silver and carry British import hallmarks, would have had the Rolex name fired into the enamel at the factory. But I suspect that Wilsdorf is stretching the facts and that it was not actually until the 1920s that he really started on this campaign. After all, if he was so impatient and really had started in 1907 with one in six, why would he have waited until 1925 to get the proportion up to four in six? That doesn't ring true to me.

For markets other than Britain I am sure that Wilsdorf would have insisted on having Rolex on the dial from an earlier date, as did other manufacturers such as Longines and IWC, so there will Rolexes from earlier than the 1920s with the name Rolex fired into the enamel of the dial, but these would not have been officially imported into Britain and so would not carry British import hallmarks. Personal imports where someone buys a watch abroad and then returns to Britain are not required to be hallmarked. If you have a Rolex with the name fired into the enamel on the dial and a British hallmark earlier than 1925 I would be very interested to see it.

Painted Names

Dial cross section
Dial cross section

Today one sees watches carrying pre-1920 British hallmarks and with the name "Rolex" on the dial. Sometimes these are not even Rolex branded watches; Marconi and Unicorn watches end up with Rolex on the dial. Why is this done? Today people are so conditioned to seeing brand names on everything that they like to see the name on the dial. Sometimes novice collectors even think that a watch without a name on the dial is not genuine. However, adding a name to a dial is easy to do, and is no surety against forgery.

In fact, most if not all early Rolex watches with British hallmarks, and names like Marconi, Unicorn etc. on the movement but with Rolex on the dial have had the name added by the simple expedient of painting it on with enamel paint. Dealers know that this makes the watch easier to sell and gets a better price, even though they know it is not original.

Original names on enamel dials were applied while the dial was being made, fired into the enamel along with the minute tracks and hour numerals. This was easy to do while the dial was being made and the most durable. The cross section through a dial here shows how enamel dials were made. A sheet of copper cut to the correct size and shape and with holes for the hands and dial feet attached, was coated with vitreous enamel, essentially crushed glass. This was then heated in a furnace until the enamel melted, bonding to the copper and forming a smooth surface. The numerals and minute and seconds tracks were then painted on, also in vitreous enamel, and the dial fired again. This melted the enamel of the numbers and other details and bonded them to the base layer of enamel. In the cross section I have shown a white enamel dial with a red 12. When the enamel of the numbers and other details melted and bonded with the underlying enamel it became virtually flat with the dial surface as the cross section shows.

If the name to be applied was not known at the time the dial was made - such as the name of the eventual retailer, then the name was painted on later with enamel paint. The importer might have offered this as part of his service to the retailer, or the retailer may have arranged himself for his name to be painted onto the dial. Enamel paint is a totally different material from vitreous enamel, it is called enamel because it forms a harder, glossier, surface than other paints such as oil paint. However, unlike vitreous enamel, enamel paint can be dissolved by a solvent such as acetone or isopropyl alcohol.

Often a retailer's name painted on to an enamel dial has partly or almost completely worn away over the years, whereas the rest of dial markings are still crisp and sharp. This is an easy indication that the name was painted on after the watch was made. However, a name painted on recently using enamel paint can be difficult to identify, it looks crisp and sharp and glossy, just like the rest of the dial. However, there are two ways in which such an addition can be identified.

If you have a pre-1925 Rolex with an enamel dial that has the Rolex name in fired vitreous enamel, not just painted on in enamel paint which can look very similar, and the case has pre-1925 British import hallmarks, then do let me know. Of course just one example is not be proof, the dial could have been exchanged, we really need a few hundred examples . . .

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Rolex's ‘Other Brands’

Wilsdorf was extremely pleased with the name Rolex and decided to reserve it as a brand name for his best and most expensive watches, which at the time meant watches made by Aegler with jewelled lever "Rebberg" movements. Often these were ‘fully jewelled’ with 15 or more jewels, but sometimes they had only seven jewels. A lever watch with seven jewels has the balance and escapement jewelled, but not the train wheel pivot bearings. Train wheel bearings that are not jewelled wear much more easily, so movements with less than 15 jewels are not fully jewelled. See Jewels for more about jewel bearings.

Wilsdorf realised that markets also existed for watches to be sold at lower price points, so over the years before World War 2 he created many other brands to fulfil this demand. Note that these were not model names for Rolex watches, like today's Submariner or Explorer, these were completely separate brand names, alternatives to the brand name ‘Rolex’, although they were sold by the Rolex Watch Company. The movements for these watches came from suppliers other than Aegler, from factories that mass produced ébauches such as Fontainemelon and Beguelin. Because of their scale of production these ébauches were cheaper than those made by Aegler, but could be just as good in quality, e.g. with Swiss lever escapements and fully jewelled. However, cheaper movements, even cylinder escapement movements, were also used for these other brands.

With such a wide range of brand names and ébauches ranging in quality from Swiss levers with 15 or more jewels down to those with cheap and humble cylinder escapements, Wilsdorf could supply a watch to suit every pocket. But this inevitably resulted in identity confusion. Such a plethora of names and price points all associated in some way with the Rolex brand detracted from Wilsdorf's aim of making Rolex a prestige brand for which he could charge accordingly high prices.

In the early days Wilsdorf often allowed names such as Rolex Watch Company, RWC Ltd. or even just Rolex itself, to be used somewhere on these supposedly lesser brands. This was to give people the vague idea that they were effectively getting a Rolex watch but at a cheaper price. Sometimes the Rolex name is seen on the dial along with one of these other brand names, such as ‘Rolex Marconi’.

This idea back-fired because it affected sales of the higher priced ‘real’ Rolex watches. One of the first steps was to remove Rolex as a single word from the other brand watches, although it was still used as e.g. part of Rolex Watch Co. Around 1945 all the other brand names except for Tudor were dropped, and eventually Tudor was floated off as a separate company.

The confusion created continues to this day, and working out whether an old watch is or isn't a Rolex ultimately comes down to whether Wilsdorf and Rolex would have called it a ‘Rolex watch’. The problem often occurs with watches that have Rolex on the dial when it shouldn't be there, when it has been added by someone in an attempt to boost the value of the watch.

It is clear that watches with brands such as Maconi, Unicorn, RolCo etc., were intended to be known as products of the Rolex Watch Co., but not as ‘Rolex watches’. These ‘other brand’ watches did not originally have ‘Rolex’ as a single word on the dial. That would clearly have identified the watch as a Rolex, and for Wilsdorf that was a definite no-no. It appears that until Wilsdorf realised what a bad idea it was, the Rolex names was allowed to appear alongside some of the other brand names. If they have the single word Rolex on the dial now, it has been painted on later, often much later.

What defines a ‘Rolex Watch’?

The Rolex Watch Company purchased watches from a number of different watchmaking companies and sold them under various brand names. So what makes one of these watches a ‘Rolex’ watch as opposed to something else? The principal distinguishing feature is that it had the single word ‘Rolex’ put on to it during the manufacturing process. Not ‘Rolex Watch Co.’, and not after it was made.

Because of this, there can be no such thing as an un-named or un-branded Rolex watch with no name on it - that is a non-sequitur. If a watch has Rolex on it, then it is either a Rolex or a fake; but if it doesn't have Rolex on it at all, it is not a Rolex.

The Name on the Dial

Watches branded Marconi, Unicorn, etc. would not have the name ‘Rolex’ on the dial as a single word on its own. That would defeat the whole purpose of creating a brand to be sold at a lower price point. If any of these watches did have a brand name on the dial, it was the same as that on the movement, i.e. a watch with RolCo on the movement would have had RolCo on the dial. Sometimes they had ‘Rolex Watch Co.’ on the dial or elsewhere, often in the case, or even sometimes ‘Rolex’ on the case or movement, or even in a few cases on the dial alongside the other brand name, e.g. ‘Rolex-Marconi’, but since it was not a Rolex watch in the eyes of Wilsdorf and Rolex, it would not have ‘Rolex’ as a single word on the dial, that would have devalued and damaged the main Rolex brand.

Watches are seen with a confusing mixture of these brand names on the dial, movement and case. Sometimes this can be rationalised by understanding what Wilsdorf was trying to achieve, but often it is a result of later modification in an attempt to make the watch more valuable. This most frequently is the addition of the name "Rolex" to a dial which never had it when it left the factory.

Logos and names are usually added using enamel paint, which looks quite convincing. If you know what you are looking for, it is easy to distinguish a name or logo added in enamel paint from a vitreous enamel dial, as I explain at Enamel Dials. Printed metal dials can be more convincing, but if the name shouldn't be there, it is still wrong and, since it is usually impossible to clean paint off a printed metal dial, an original dial has been ruined in the process.

The Other Brands

The first of Wilsdorf's other brands, registered in July 1909, was "Omigra". This looks suspiciously like Omega, a name that was well known and prestigious long before 1909, when the name Rolex still new and unknown. Wilsdorf must have had second thoughts about this and the registration was cancelled four months later at his request. Another brand registered by Wilsdorf that didn't get off the starting blocks was Elvira. Other names included Rolwatco, Falcon, Genex, Lonex, Rolexis, Lexis, Hofex and Wintex.

One of the next brand names created by Wilsdorf was Marconi, after the inventor and wireless telegraphy pioneer. Marconi Lever was registered on 24 January 1911. This was followed by Unicorn Lever (registered 17 March 1919) and Unicorn Watch (registered 20 November 1923).

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Marconi Lever General Watch Co. movement
Marconi Lever: General Watch Co. Movement.

Soon after creating Rolex, Wilsdorf soon decided to increase his revenue by creating parallel brands that would sell at lower price points. The Marconi name was the first to be used to any great extent. The brand name ‘Marconi Lever’ was registered on 24 January 1911. Wilsdorf said that these watches were to be sold through ‘parallel’ channels, i.e. not through Rolex dealers.

Marconi watches have non-Aegler movements, and Marconi watches in gold or silver cases imported into Britain often (usually?) have the ‘GS’ sponsor's mark of Stockwell & Company rather than the Wilsdorf and Davis W&D sponsor's mark. I suspect that watches that have movements marked Marconi and cases with the W&D sponsor's mark are most likely marriages rather than original pairings.

Stockwell & Co. were international carriers who, after June 1907, also acted as Assay Agents for clients who didn't have British branches. Wilsdorf & Davis were based in London and had registered their W&D sponsor's mark in 1907 so they didn't require this service from Stockwell & Co., although it is quite likely that they used Stockwell to transport watches from Switzerland to the UK. The use of Stockwell as assay agent for some Marconi watches suggests that in these cases Wilsdorf was trying to hide the connection between the Marconi and Rolex brands. Marconi branded watches are also seen in cases with Wilsdorf & Davis' sponsor's mark and the RWCo. Rolex Watch Company trademark.

Sometimes watches are seen with ‘Rolex Marconi’ or ‘Rolex Marconi Special‘ on the dial. I have seen enough Rolex Marconi now that appear to be genuinely old to convince me that at least some of these are genuine, although I am less convinced about the ‘Rolex Marconi Specials’.

With regard to watches marked Rolex Marconi, I think that in 1911 Marconi was Wilsdorf's first venture into creating a cheaper line of watches, and marketing of any sort (in Europe) was in its infancy, so he thought that by calling them ‘Rolex-Marconi’ people would recognise that they were not Rolex watches but another brand with some of the Rolex cachet. Which of course backfired - people simply thought that they could get a Rolex watch at a lower price. This type of dual ‘Rolex+’ branding was not repeated on later ‘other brands’. Today the connection between Rolex and Marconi is well known and Marconi watches are often described as simply ‘Rolex’ watches, which is not right; at most they are ‘Rolex-Marconi’, and some have no doubt been ‘upgraded’ from simple Marconi watches.

The principal problem with the Marconi name was that it was first and foremost an extremely well known as a company supplying wireless telegraphy equipment, to the RMS Titanic amongst many others. By advertising the Marconi name (with their permission?) Wilsdorf was in fact promoting someone else's brand, which he soon realised was not a good idea.

The movements of Marconi branded watches are often engraved on the central bridge with "Marconi Lever". All the movements that I have seen and identified were made by the General Watch Company. This was founded as "La Generale" by the Brandt brothers, who also founded the Omega Watch Company. The General Watch Company was created to manufacture watches aimed at the lower end of the market. In 1906 the Brandts withdrew from involvement with the company and it went its own way, soon diversifying into better quality watches with lever escapements. They made watches with the brand name "Helvetia".

Wilsdorf & Davis and Stockwell & Co.

Stockwell & Co. were a large company of British carriers with links to international carriers. They specialised in the transport of watches from Switzerland to Britain. From June 1907 they also acted as Assay Agents for some of their clients who imported watches in gold or silver cases.

Wilsdorf & Davis almost certainly used Stockwell & Co. to transport all their watches from Switzerland to London, and they also used Stockwell & Co. as assay agents for some of their watches, such as the Marconi watches discussed above. Wilsdorf & Davis had registered their own W&D sponsor's mark in 1907 so they didn't necessarily require this service. There were two reasons I can think of why Wilsdorf & Davis would have used Stockwell & Co.'s assay agent service. (1) To disguise the connection between an unbranded or "other brand" watch and Rolex. In this case, only Stockwell's GS sponsor's mark appears on the case. (2) When the assay offices that Wilsdorf & Davis were registered at had a long backlog of work. In this case, sometimes both the W&D and GS sponsor's marks are seen on watch cases.

‘Marconi Lever’ Wristwatch

Sometimes early wristwatches turn up with some allusion to Rolex on the dial. Often this is fake and has been added later to boost the perceived value of a watch. The wristwatch shown here caught my eye; as soon as I saw it I doubted that the ‘Rolex Marconi’ wording on the dial was original or genuine.

There were two principal reasons that I was suspicious; firstly, watches of this age that were sold in Britain didn't carry manufacturer's names or logos on the dial and, secondly, Marconi was created by Hans Wilsdorf to be a brand that was separate from the main Rolex brand, so the two names should not be seen together like this.

It is recorded in the book by Dowling and Hess that Hans Wilsdorf registered the name ‘Marconi Lever’ on 24 January 1911. They also say that the Marconi brand was first used on a watch in 1920. Dowling and Hess note that Marconi watches were sold through ‘parallel channels’, which meant dealers who were not Rolex agents.

The Watch

Marconi Lever Wristwatch Case Back: click image to enlarge.

Marconi Lever Wristwatch Face: click image to enlarge.

The watch is a typical trench watch, which were in great demand by newly commissioned officers heading for the front line in the Great War. It has wire lugs, an unbreakable crystal, as original but replaced, and skeletonised hands and numerals to take radium luminous paint, of which traces remain.

The case has London Assay Office import hallmarks inside the back for sterling silver, the date letter "b" for 1917 to 1918 and sponsor's mark GS for Stockwell & Company.

The case also has a W&D mark. It is not clear why it has this second sponsor's mark, clumsily struck at an angle and with a wobbly ‘W’, in addition to the GS sponsor's mark. The shield is the right shape and the mark looks like one recorded in Culme, but the low resolution of the images in Culme make an exact comparison impossible. However, the mark looks more like an engraving than the clear impression made by a punch and it could just be an engraved copy of a genuine mark.

The Movement

Marconi Lever Wristwatch Movement: click image to enlarge.

The movement was made by the General Watch Company of Bienne, originally founded by the Brandt brothers who also founded Omega.

The movement is a typical of the time Swiss split-plate movement, with a lever escapement and jewelled to the third hole for a total of 15 jewels. The balance is plain and the balance spring appears to be blued steel, so it is not compensated for changes in temperature. The screws in the rim of the balance, which in a compensation balance would be used to adjust its temperature compensation, are steel and are only there for show. Lever escapement movements were the best technology for wristwatches at the time, and this one is of middle quality; fully jewelled but not temperature compensated.

The engraving of the name ‘Marconi Lever’ on the movement looks to me like it is original and I have no hesitation in saying that the movement is a genuine Marconi Lever, made by the General Watch Co. and sold by the Rolex Watch Company. However, the engraving of a brand name onto the movement was unusual before the 1920s. Branding of watches was something that was unusual in Britain at that period, and something that British retailers were quite opposed to. So whether this movement is from the same period as the case or actually a few years later is open to question.

The Dial

The dial is enamel, which means it is made of vitreous enamel, a glass like material. The white background and the black numbers and tracks are fired at high temperature in a furnace, which bonds them together. I was suspicious that the name logo ‘Rolex Marconi’ had been added later. This is easy to tell.

Marconi Lever Wristwatch Logo: click image to enlarge.

Marconi Lever Wristwatch Dial: click image to enlarge.

A quick look at the dial using a hand lens shows that the "Rolex Marconi" on the dial is enamel paint, not fired into the vitreous enamel of the dial. I have tried to show this in the two pictures here, although it is not easy to show with a photograph. With the dial under a lens or microscope it can be turned to catch the light which shows up the logo as an addition really clearly.

The image with the red lines shows that the logo is not horizontal with the numbers, but also notice that the logo appears blacker than the numbers and tracks. This is because the black vitreous ink used to make the numbers and tracks mixes a little with the white enamel of the dial as it is fired, which takes away some of the intensity of the black, whereas the logo has been applied in black enamel paint which just sits on the surface of the dial.

The second image was illuminated with a strong oblique light and shows how the enamel paint of the logo really stands out from the surface of the dial in a way that the fired numerals and tracks don't. See also how crisp and sharp the logo looks compared to the rusty old hands and traces of original luminous paint on the hands and numbers. Would paint applied to the dial at the same time that the hands and the original luminous paint were new really still look like that? No; genuinely old enamel painted logos dull from oxidation and dirt, and are usually flaked off partially or even nearly completely, over the intervening years, like the example shown at Fired or Painted?.

It is clear that the ‘Rolex Marconi’ logo was added after the dial was made. How long after we don't know, but my conclusion is that someone has quite recently ‘enhanced’ an original Marconi Lever watch. There are two reasons why I think this was done quite recently:


The logo is not part of the dial, and was not added to the dial when the watch was made. It has been added to the dial later in enamel paint, the condition of which shows that it is not very old.

In view of the hallmark date in the case and the 1920 date for the first use of Marconi quoted by Dowling and Hess, the suspicious second sponsor's mark, and the engraving on the movement, there must be a question as to whether the case and movement started life together or whether this watch is a marriage. The dial and hands are of the correct style for the period of the case, although use of dials and hands like this continued after the war, but the engraving on the movement is unusual for the period and looks out of place.

This watch would not have had any manufacturer's name on the dial when it was new, which gives the game away even before studying it in detail. But watches like this with ‘Rolex Marconi’ and similar legends are seen quite often. This one is clearly a fake, but are they all? I think that they probably are, that Wilsdorf would not have allowed the Rolex name to appear like this on a watch that was supposed to be sold as a completely separate brand; it was not supposed to be a ‘Rolex’ watch, even if it was sold by the Rolex Watch Company. If you think that you have evidence to show otherwise, then please do get in touch!

Rolex Marconi Special

With regard to watches marked ‘Rolex Marconi Special‘ on the dial, the brand name Marconi Special was registered by Wilsdorf on 31 August 1923, but I think that by the 1920s Wilsdorf had realised the error of conflating the Rolex and Marconi brands and these would not have been branded as Rolex watches, although they would have carried some allusion to an association with the Rolex Watch Company.

There are a lot of these coming out of Argentina at the moment (2019), often described as ‘VINTAGE & FINE ROLEX MARCONI SPECIAL HAND WINDING 1940 WRISTWATCH’. As far as I can make out, Rolex dropped the name Marconi in the 1920s and certainly weren't using it in the 1940s. These watches have dials that are in much better condition than the watches themselves, which are usually pretty badly corroded, so it is clear that the dials have been repainted. All of these are obviously fakes and in most cases have nothing at all to do with Rolex. It appears that someone in Argentina has set up to take anonymous watches, redo their dials and hey presto! brand new 1940s Rolex Marconi Specials!

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Unicorn, ROLCO, etc.

The Marconi name was soon dropped in favour of "Unicorn". One problem with the name Unicorn was that because it was already in common usage it could not be registered as a unique name, hence the registration of "Unicorn Lever" and "Unicorn Watch". But anyone could register another phrase using an image or the word unicorn, as many had already done.

I found a number of registrations of trademarks with unicorns, the earliest being Gabus & Fils in 1887, followed by Courvoisier Freres in 1895, Wittnauer & Co. in 1901, J. Ullmann & Cie in 1912, and so on. I am surprised that Wilsdorf wasn't aware of these, but it is clear that he soon realised that Unicorn wasn't sufficiently unique as a brand to be valuable. Some time later, probably after the Second World War, Adolf Schild (A. Schild ), used the name and an image of a unicorn as a trademark or brand.

Wilsdorf then started using more unique names such as ROLCO, Oyster Watch Company (which understandably confusing since there was also a Rolex Oyster watch) and many others, one of the best known these days being Tudor, which is discussed in a separate section further down this page.

BTCo. Rolco movement
BTCo. Rolco movement: Click to enlarge

The image here shows a ROLCO branded watch movement. This movement was manufactured by Beguelin & Cie S.A. or BTCo., who also manufactured watches under names Damas and Tramelan Watch Co.. This movement has been customised for Rolex by modifying the shapes of the bridges and cocks and putting the name ROLCO on the ratchet wheel. Beguelin also supplied the same movement to other companies including Ingersoll and these movements were made to look different so that it was not obvious that they were all from the same manufacturer. Apart from the shape of the bridges and cocks, all the other parts of these movements (bottom plate, train wheels, escapement, keyless work, etc.) were identical. You can see five different versions of this particular BTCo. movement on the movement identification page.

There was never any secret that Marconi, Unicorn, etc. watches were made for the Rolex Watch Company, but they were not called Rolex watches and not (usually) branded "Rolex". The distinction he created was subtle, but Wilsdorf was a master salesman, perhaps the first modern marketing expert, and he was manipulating names and brands to alter the way things were perceived. Omega did the same thing with Tissot; In "Omega - A Journey through Time" Marco Richon explains that in 1935 an economic collapse in Brazil made it impossible for Omega to maintain sales at Omega's normal price points. Rather than cut prices of Omega watches just for Brazil, which would have inevitably affected Omega branded watches sold in other markets, the company withdrew Omega marketing and sales from the country and sold watches branded "Omega Watch Co. - Tissot" at lower price points in Brazil.

In 1952 Wilsdorf is reported as saying For some years now I have been considering the idea of making a watch that our agents [emphasis added] could sell at a more modest price than our Rolex watches, and yet one that would attain the standards of dependability for which Rolex is famous. I decided to form a separate company with the object of making and marketing this new watch. It is called the Tudor Watch Company. Of course by this time Wilsdorf had been selling Marconi, Unicorns and all sorts of other branded watches, but the significant point here is that the Tudor watch was to be sold by Rolex agents alongside Rolex watches. The implication of this is that the brands other than Tudor were not sold alongside Rolex watches or by Rolex agents.

Today one sees Marconi, Unicorn, ROLCO, Tudor, etc. watches being advertised (not by Rolex I hasten to add) as "early Rolexes". Although this is not accurate, ephemeral things like brand identity are not black and white, which is clearly also what Wilsdorf himself had in mind when he created these other brands. Wilsdorf wanted purchasers of the "other brand" watches to feel that they were getting a Rolex at a cheaper price, whilst at the same time he was busy persuading other people that it was worth paying more to get a real Rolex, a watch with the Rolex brand name on it.

These were early days for marketing and branding. Wilsdorf tried to create a situation where the "Rolex Watch Company" marketed watches branded as Rolex, and also watches branded Marconi, Unicorn, ROLCO, Tudor, etc. These were sold at different price points, with Rolex branded watches being the most expensive and the other brands filling lower price points, so that there was a watch for every customer no matter what they could afford. The Rolex Watch Company name being associated with all the different brands would give customers reassurance that whatever they paid, they were getting a good quality watch. Unfortunately, most customers were not interested in what was inside the watch, whether it was a fully jewelled lever escapement movement made by Aegler, or a cheaper mass produced movement from one of the &ecute;bauche factories. And no doubt some retailers didn't draw this to their attention.

Soon all these other brands were thought of simply as "Rolex watches" and Wildsorf's carefully differentiated marketing strategy and price structure collapsed. If one could buy a "Rolex watch" with the Unicorn brand on it at a fraction of the price of a "Rolex watch" with Rolex on it, why would anyone pay the higher price. This was not what Wilsdorf had intended. He wanted people who could afford them to buy Rolex branded watches, and others who were less well off to buy one of the cheaper brands. But because of the deliberate association of the Rolex name with the cheaper brands, sales of those soared whilst more expensive watches sat on retailer's shelves. After struggling to differentiate the different brands and their price points, Wilsdorf gave up and all the other brands were dropped. Only Tudor was retained, eventually spun off as a separate company.

I have seen watches from the Great War era with BTCo. movements in silver cases that have the W&D sponsor's mark and "Rolex" in the case back and "Marconi lever" on the movement. Is this a Rolex? I would say no; it doesn't have an Aegler movement and is branded Marconi. Why is the Rolex name in the case back? It might have been punched by mistake or, more likely in my view, Wilsdorf was less careful in the early days about where he splashed the Rolex name. Perhaps he thought he could endorse lower priced Marconi watches with the Rolex name without people calling them Rolex watches. He would have quickly realised that this was a mistake.

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Oyster Watch Co.

Oyster Watch Co. Case Back: Click to enlarge.

Oyster Watch Co. Movement: Click to enlarge.

Oyster Watch Co. Movement: Click to enlarge.

The movement and case back shown here are branded Oyster Watch Co. The case back has the same list of patents found in the case backs of Rolex Oysters, and the SAR under a coronet trademark, so there is no attempt to conceal its connection to the Rolex Oyster. But this watch was made with a cheaper injection moulded case and was intended to sell at a lower price point than a Rolex watch.

The bottom plate of the movement has the FHF trademark of Fontainemelon showing that they manufactured the ébauch. It's a 10½ ligne FHF 30 movement ticking at 18,000 vph. It has a Swiss straight line lever escapement and fifteen jewels, so it is a good quality movement. Fontainemelon mass produced ébauches so perhaps this would have been cheaper than an Aegler ébauch, but similar in quality to Aegler's own 15 jewel movements. It is marked "unadjusted", which I think was put onto movements to make them cheaper to import into America, adjusted movements being charged a higher rate of import duty.

Oyster Watch Co. Case Back: Click to enlarge.

This Fontainemelon movement was also used in Tudor watches, when it was called the Tudor calibre 59. There was also a centre seconds version called the 59(SC). The Fontainemelon reference for this movement was FHF 30-1. Although the Tudor version is usually described as being ‘based on’ the Fontainemelon movement, the only modification seems to be the engraving of the Tudor name on the bridge. This was almost certainly done by Fontainemelon as the ébauche was being made.

The case of this Oyster watch is made from the "Snowite" injection moulding zinc alloy. This is a very poor quality material and, although it is chrome plated, the back very heavily pitted on the outside. I don't have the other parts of the case so I don't know how well they survived, the case back was against the wrist and some people's perspiration can cause corrosion damage, even on some grades of stainless steel. This case is particularly bad.

Later watches with Snowite front parts to their cases have stainless steel backs to avoid this. However, even the front parts of Snowite cases can suffer from heavy corrosion. It is not a good material.

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Tudor dial with Rolex Watch Co. Thanks to Ray in Australia for the image.

The first mention of the Tudor name was in 1926 in a rather strange context. On a piece of notepaper headed "Horlogerie H. Wilsdorf, Bienne" there is a declaration by "vve. de Philippe Hüther" (the widow of Philippe Hüther) that she has registered the name "The Tudor" at the request of the company of H. Wilsdorf, and that she recognises that the brand is the exclusive property of that company and that it retains all rights to it. The implication of this is that the vve. de Philippe Hüther had been using the name Tudor but that Wilsdorf had proved a prior claim to it so she agreed to register the brand and that Wilsdorf's company would have exclusive rights to it in the future.

Tudor Advert from 1961

The Tudor brand was little used before WW2 except for watches sold in Australia. The image here shows the dial from one of these, which in addition to "Tudor" clearly carries "Rolex Watch Co. Ltd". Surely anyone could be forgiven for thinking that this was a model of Rolex watch, not a completely separate brand.

Many watches sold in Australia have cases that were made by Australia's largest case maker, J. W. Handley in Melbourne. Handley made cases for Rolex, Tudor, Unicorn, Cyma, Omega, Tissot and many others. This was to reduce import duties on Swiss watches imported into Australia. Duties were lower on uncased movements because they were considered to be ‘parts’ which facilitated local employment of craftspeople. Also, the case, especially a gold case, was a significant proportion of the cost of a finished watch. A case in sterling silver cost about the same as the movement, a gold case considerably more. Making the cases locally reduced considerably the value on which import duty was levied.

The ébauche shown here from an Oyster Watch Co. branded watch is a Fontainemelon calibre 30, cal. FHF 30; it was also made in a centre seconds version FHF 30-1. It's a 10½ ligne diameter round movement ticking at 18,000 vibrations per hour. It has a Swiss straight line lever escapement and fifteen jewels, so it is a good quality movement. It was also made in a 17 jewel variant with end stones for the escape wheel bearings, and an indirect centre seconds version called the FHF 30-1.

Fontainemelon Movement: Click to enlarge.

This ébauche was widely used in the Rolex Watch Company's ‘other brand’ watches such as Oyster Watch Co. and Tudor. In Tudor watches it was called the calibre 59 and the centre seconds version called the cal. 59(SC). Although the Tudor version is usually described as being ‘based on’ the Fontainemelon movement, the only modification seems to be the engraving of the Tudor name on the bridge.

In 1946 Wilsdorf decided to create a completely separate company to sell Tudor watches and so "Montres Tudor S.A." was registered. An an S.A. is a "Société par Actions" or joint-stock company in English, a company owned by shareholders and run by a board of directors. In this case it appears that the shares in Montres Tudor S.A. were wholly owned by Rolex S.A. rather than being publicly offered.

The relationship between Rolex and Tudor caused the advertising copywriters to dance a merry jig. In early trade adverts it was said that Tudor was "sponsored" by Rolex. Later Tudor adverts such as the one from 1961 reproduced here said that they were "made" by Rolex. The use of the word "made" in this context is stretching the normal meaning of the word rather beyond breaking point in my view, since Rolex didn't actually make anything; the ébauches, dials, hands, cases, straps and bracelets of all Rolex, Tudor, Marconi, Unicorn, ROLCO, etc. etc. watches were made by companies not owned by either Wilsdorf or Rolex.

Emphasis on the (lower) price point of Tudor watches was relentless. Advertising copy said that Tudor watches were "... for the man whose purse is modest, yet whose aspirations are high." The ruggedness of Tudor watches, the waterproof case of the Tudor Oyster, the high quality of the watches, were repeatedly emphasised. Surely only somebody who worked in the advertising department could convince themselves that they were really advertising something completely separate and different to the more expensive "real" Rolex watches. Or am I just too cynical? Actually, these trade adverts were not supposed to be seen by the public - but what salesman sensing a potential sale and commission would resist mentioning the Rolex connection.

In fact, the technical differences between a Tudor watch and a Rolex watch were vanishingly small; even the advertising department couldn't come out with a convincing explanation of precisely what the difference was. The only really significant difference was in their prices. It was therefore understandable that people thought that a Tudor was a cheap Rolex, it just didn't carry the bragging rights of its more expensive stable mate. Which is why a lot of Tudors and other early Rolex Watch Co. watches have been "upgraded" in more recent years by having Rolex added to their dials or movements.

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When Is a Watch Really a ‘Rolex Watch’?

Is a watch with the name Marconi, Unicorn, ROLCO, Tudor, etc. on the movement, or marked Rolex Watch Co., or with the W&D sponsor's mark in the case back, actually an early Rolex watch? In the semantically complicated marketing world of Hans Wilsdorf the answer has to be emphatically No.

These other brand watches were made for, or sold to, the Rolex Watch Company, but they would not have called any of them a Rolex watch. The other brands were not model names of Rolex watches, they were intended to be completely separate and, let's be brutally clear, cheaper brands. They used non-Aegler movements so that they looked different, and they were sold at lower price points. Whether they actually cost less to make is not the point. After the problems caused by the initial Rolex-Marconi mistake they were called simply a Marconi, Unicorn, Rolco, etc., watch. Wilsdorf didn't want to hurt sales of premium priced Rolex branded watches by associating these other brands too closely with the Rolex name, but of course it was inevitable that people did do that, especially in the resale market.

A watch with one of these other brand names is correctly described as a Rolex Watch Company product, but not as a Rolex watch, even though it clearly is a watch that was sold by the Rolex Watch Company.

This then opens the question as to how to identify a "Rolex watch". The short answer must be that it is a watch that Hans Wilsdorf himself would have called a "Rolex watch" and which would have had the name Rolex put on it clearly at the point of manufacture.

By far the easiest identification for very early Rolex watches is that they had Aegler "Rebberg" movements. But Aegler didn't stand still and new calibres were developed that succeeded the Rebberg. But the fact remains that almost every Rolex watch ever made has an Aegler movement of some sort. If a watch doesn't have an Aegler movement, or one of the small number made with movements from other manufacturers, e.g. from Valjoux for chronographs which Aegler didn't make, then it isn't a Rolex watch.

Some early Tudor watches have Tudor on the dial along with the name of a Rolex model such as Oyster Prince, and, even going so far as to mark them with "Rolex Watch Co." on the dial or with "Rolex" inside the case back along with the Rolex trademark crown with five points with balls on their ends. The dial shown in the photograph here is clearly meant to be that of a watch of the brand "Tudor", but it also has "Rolex Watch Co. Ltd." around the sub-seconds dial. Is this a Rolex watch? The Rolex Watch Co. Ltd. wouldn't want you to say so, although they might want you to think so — at least while you were in the shop and reaching for your wallet.

It is clear that Wilsdorf wanted to give Tudor watches more than something of the lustre of the Rolex brand without actually calling them Rolex watches. However, this confused the identities of the two brands, which was not a good idea for either. Tudor was later separated from the Rolex brand and floated off as a completely separate company that stopped using the Rolex name and trademarks on its watches.

However, and this is probably the critical point for most people who are not professional hair-splitters, a watch made with one of these "other" Rolex brands would not have left the factory with the single word "Rolex" as a brand on the dial. If such a watch has the single word "Rolex" on the dial now, then that has been added later by someone else. You don't think that whoever did that might have been trying to deceive, do you? Dear me, what an unpleasant thought. As always, caveat emptor: don't believe everything that you read or are told.

Unmarked or Unsigned Rolex?

I was contacted by a correspondent who had purchased a trench watch and identified the movement as a Beguelin (BTCo.) from my Movement Identification page. From this he also knew that Beguelin supplied watches to Rolex. He told me that there are no markings on the case but the dial and crown are identical to many pictured Rolex on Google. His question was ‘Is it an unmarked Rolex?’

I explained that Rolex didn't actually make watches, they bought them from manufacturers such as Aegler, Fontainemelon, and Beguelin. Those manufacturers also supplied watches to other companies, so the only thing that distinguishes a watch supplied to Rolex from one supplied to another company are markings on the watch, such as the W&D sponsors mark, or the name Rolex or Rolex Watch Co., or the name of one of their ‘other brands’. Therefore there can be no such thing as an ‘unmarked Rolex’. If there is no Rolex related branding on the watch, it has nothing to do with Rolex and is simply an unbranded watch.

Beguelin movements were not used in Rolex watches. They were used for other Rolex Watch Co. brands such as Rolco, Marconi or Unicorn. Any watch with a Beguelin movement and Rolex on the dial has had the name on the dial added later, Wilsdorf and Rolex did not use the Rolex name for these watches.

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W&D Watches with Cylinder Movements

W&D Cylinder Movement
W&D Cylinder Movement: Click to enlarge
W&D Cylinder Hallmarks
W&D Cylinder Hallmarks: Click to enlarge

Watches sometimes turn up with the W&D sponsor's mark and very basic movements with cylinder escapements. The images here are of one of these that was auctioned on eBay, and I have seen at least two others virtually identical.

The inside of the back of the silver case has the Wilsdorf and Davis W&D sponsor's mark, which shows that it was imported into the UK by their company. The case was punched with their sponsor's mark before being sent to an assay office to be assayed and hallmarked. The hallmarks are London Assay Office import hallmarks for .925 (sterling) silver. The sign of Leo is the ‘town mark’ used by the London Assay Office on imported items. The date letter, a Gothic ‘b’ in cameo, is for the hallmarking year from 29 May 1917 to 28 May 1918.

The movement is very basic. It has a cylinder escapement and no train jewels. The red stone at the centre of the regulator is the upper end stone for the balance staff, so it looks like it has four jewels, two end stones and two jewel holes for the pivots of the balance staff. The very best cylinder escapements made by the likes of Breguet had ruby cylinders, but this one will have a steel cylinder. There is nothing particularly wrong about movements with cylinder escapements, when new they were capable of quite good time keeping but they do require very regular cleaning and oiling. They were mass produced by Swiss manufacturers in the nineteenth century in millions. The finish and lack of jewelling on this one identifies it as being one of these mass produced movements and very cheap.

So why were Wilsdorf and Davis handling these very basic and cheap watches? There is no name on this one, indeed nothing to identify it other than the W&D mark. There is certainly no suggestion that it is a Rolex watch, despite what some vendors might like you to think. The ones I have seen are all wristwatches, and all are dated from their hallmarks to the time of the Great War, during which there was a tremendous demand for wristwatches from men heading for the front. I suspect that this was simply ‘making hay while the sun shines’. When there was such a tremendous demand for anything in wristwatch form, who would resist importing and selling whatever they could get their hands on?

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Timekeeping Precision

Wilsdorf was a perfectionist and never ceased pressing Aegler to improve the timekeeping of watches they made for him. In 1910 Aegler submitted as its manufacture a Rolex wristwatch to the Bienne testing station at the School of Horology. On March 22nd 1910 this watch received a First Class certificate and thus became the first wristwatch to be officially certified as a chronometer in Switzerland.

NB: Chronometer refers to a precision watch that is tested in various temperatures and positions, thus meeting the accuracy standards set by the official institute in Switzerland, which is only achieved by the finest quality movements. It should not be confused with Chronograph, which refers to any watch with a stopwatch function, whether the time keeping is of high accuracy or not.

On July 15th 1914, a small 11 ligne (25mm diameter) Rolex wristwatch received a Class A precision certificate from the prestigious Kew Observatory in England. This was the first time that a Kew "A" certificate had been awarded to a wristlet watch, and required that the watch pass the same tests as large marine chronometers. The watch was tested over 45 days in five different positions and three different temperatures, including ambient (65 degrees Fahrenheit), oven-hot, and refrigerator-cold. Wilsdorf said that this was a red letter day in the development of the firm, a day that he would never forget. Wilsdorf asked Aegler from then on to submit all Rolex calibres for chronometer tests. The ability of a wristwatch to maintain accurate time keeping could no longer be doubted.

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English Made Gold Cases

With the outbreak of the Great War (World War One or WW1), officers and soldiers going to the front wanted reliable and accurate wristwatches and, because they were not issued with them as standard equipment, they bought their own. Officers were given an allowance to buy their kit, uniform, sword, revolver, etc. including a wristwatch, which every officer was expected to have. This presented an opportunity for Wilsdorf to sell more wristwatches, but the war also gave rise to a serious problem for importers of watches.

Before the war London had become the export centre for Wilsdorf and Davis for overseas markets as well as Britain. Every watch was examined in London before being sent to the retailers, whether British abroad. By 1914 the London company had grown to such an extent that it was occupying a large suite of offices and had a payroll of more than 60 employees.

In 1915, as part of the war effort, the British Government imposed an ad valorem duty of 33⅓% on imported luxuries, which included clocks and watches, to conserve foreign currency reserves. This meant that any watches imported into London, even if only for checking before subsequent export abroad, would be subject to this high rate of tax.

B&S gold cased watch
English B&S gold watch case for Rolex.
Image courtesy of and © John B, August 2016.

Wilsdorf and Davis had in 1912 opened an office in the Aegler factory in Bienne to facilitate their close business relationship with Aegler. As a result of the British import duty, to avoid paying the tax on watches not destined for the British market, Wilsdorf moved his main Swiss office from La Chaux de Fonds to Bienne, and expanded the function of the consolidated office to include checking all the watches he purchased from Aegler, whether they were bound for London or elsewhere, so that watches bound for countries other than Britain did not need to pass through London. For the time being the head office of Rolex remained in London.

Watches bound for Britain continued to be made and cased in Switzerland, except for gold watches of all grades. For gold cases for watches to be sold in Britain during the period of high import duty, Wilsdorf turned to English case makers such as The Dennison Watch Case Co. in Birmingham, England, to avoid the import duty. Silver watches, which attracted less tax because of their lower price, continued to be made and cased in Switzerland.

The wartime tax started a trend of gold watch cases being made in England. In addition to Dennison, Wilsdorf also had cases made by other English makers. The image here shows a gold case made by B H Britton & Sons; Charles Henry Britton, Walter Britton and Herbert Britton, of 35 Hockley Hill, Birmingham, England. The sponsor's mark B & S was first entered at the Chester Assay Office in 1912. This shape mark was first registered in May 1931. The hallmarks in this case are Chester Assay Office marks for a nine carat gold item made in Britain. The date letter "J" is for 1959 to 1960, showing that the trend for having gold cases made in England that started in 1915 continued long after the Great War, and after the Second World War.

In 1919 Wilsdorf decided to relocate the headquarters of Rolex from London to Geneva.

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My Grandparents' Rolexes

In 1918 my grandfather purchased a pair of Rolex watches for himself and my grandmother. You can see them together in the photograph below, and then the dial, movement and inside case back of my grandfather's watch.

My grandfather's watch has a clean white enamel dial with a beautifully simple design; sharp black arabic numerals on a crisp white enamel background, the 12 being picked out in red. This makes it very easy to read, probably the clearest dial I have ever seen, one of the benefits of white enamel that has never really been equalled. The hands are elegant and perfectly proportioned, the minute hand being a slender baton and the shorter hour hand a lunette style.

My grandmothers watch has a silvered dial with Roman numerals, again the 12 (XII) is picked out in red, and the hands are the same design as on my grandfather's watch.

My grandfather's watch has a 35mm diameter case with a 13 ligne A "ligne", (pronounced "line"), is 1/12 of an old French inch (pouce), used prior to the adoption of the metric system. A ligne is 2.256mm. It is used in the measurement of watch movements, and is the outer dimension of the movement just beneath the flange that holds the movement in place in the case. The shorthand for ligne is the triple prime ‴, e.g. 12.5‴. Aegler Rebberg movement. The plates and bridges have a beautiful engine turned perlage pattern. The small crown wheel is engraved “SWISS MADE” and the larger ratchet wheel “ROLEX 15 JEWELS”.

Inside the case back are, from the top, the sponsor's mark “W&D” in an oval shield with points top and bottom, then “.925” in an oval, the UK symbol for silvery purity of 92.5% or sterling silver, a mark that looks like an omega symbol on a cross in an oval shield, the London Assay Office town mark used on imported silver, and below these the date letter, a gothic “c” for 1918/1919. Underneath the British hallmarks are the Swiss hallmarks of a bear rampant and 0.935, the Swiss higher standard of silver until 1933. Either side of these are stamped “Rolex” and “ SWISS”.

mr1 (43K) mr2 (11K) mr3 (17K) mr4 (13K)

The movement of my grandmother's watch is exactly the same as my grandfather's watch only smaller, with a 10½ ligne Rebberg movement. The inside back of the gold case is marked “Dennison Watch Case Co.”, the Birmingham watch case manufacturers. It has the “9” and “⋅375” hallmarks for 9 carat gold, the anchor used the Birmingham Assay Office on native British manufactured items, and a date letter “s”for 1917/1918. The Rebberg movement was evidently imported from Switzerland but cased in England, to avoid high import duty imposed during the war years.

The presence of import hallmarks in the case of my grandfather's watch shows that it was cased in Switzerland before being imported, whereas the native British hallmarks in my grandmother's watch show that the movement was imported bare and then cased in England. The extra cost of the ad valorem duty of 33⅓% imposed on imported luxury items such as clocks and watches during the war years evidently did not make it worthwhile to use English silver cases, but it was worthwhile for gold cases. There is much more about hallmarks and date letters on the pages beginning with my Casemarks page.

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The Rise of the Rolex Brand

In Britain there was a tradition that it was the name of the retailer that appeared on watches. Wilsdorf realised that as long as the retailers continued to put their names on the dial, they had control of what they purchased and sold, because they could put their name to any watch they chose. Although by having the movement and case branded with the Rolex name Wilsdorf could build up a reputation with the retailer, this would mean nothing to the customer who would rarely if ever look inside his watch. Wilsdorf was determined to produce the best wristwatches possible, believing that this was the key to success. He also realised that he would get better orders and more control over the wholesale price of his watches if he could build up demand so that customers would go into the shop and ask for, or better still insist on, a Rolex watch by name.

In addition to the various publicity events, such as obtaining the world's first chronometer certificates for his wristwatches, Wilsdorf began to push forward the Rolex brand. Initially he applied labels to the back of the watches, but this was not enough. So from 1921 he began to ship watches with the Rolex name printed on the dial. At this time watches were shipped in small boxes, each containing 6 watches. To start with only one watch in each box had the Rolex name on the dial, then later two of them, and slowly he increased the number of Rolex branded watches sold. However, this was too slow for Wilsdorf and in 1925 he started an intensive advertising campaign costing £12,000 each year. In 1925 Rolex registered the crown symbol as a trademark. Wilsdorf writes that the retailers gradually accepted that four, and then five out of every six watches were branded Rolex.

With the launch of the waterproof Rolex Oyster in late 1926, Wilsdorf was able to insist that all Oysters should have Rolex on the dial. Wilsdorf continued his advertising campaign in support of the increasing branding of his watches, culminating on November 24, 1927 when he took over the whole of the front page of the Daily Mail, at a cost of £1,600, with a full page advert for "The marvellous Rolex wristwatch - The World's best by every test" and stated that "All Good Jewellers throughout the British Empire stock Rolex watches". By his branding and advertising campaigns, Wilsdorf effectively turned the tables on the retailers: no longer would he have to approach retailers and ask them to stock his watches, customers would demand Rolex branded watches, and the retailers would have to come to him!

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Dust and Water Resistant Cases

Being a perfectionist, attaining a class A precision certificate from Kew only spurred Wilsdorf on to addressing another shortcoming of the wrist watch: its susceptibility to dust and damp. In the wristwatch's unprotected position on the outside of the wrist, unlike a pocket watch, it was exposed to impacts, moisture, and dust. Shipments of wristwatches sent abroad were often found to have rusted by the time they arrived from exposure to dampness. Wilsdorf was not the first person to attempt to make a waterproof watch - many earlier watches are described on my page about waterproof watches - but he was by far the most commercially successful.

In the Rolex Jubilee Vade Mecum Wilsdorf writes "To my technical assistants, my constant refrain was, from the earliest days: We must succeed in making a watch case so tight that our movements will be permanently guaranteed against damage caused by dust, perspiration, water, heat and cold. Only then will the perfect accuracy of the Rolex watch be secured."

With the end of the first world war (WW1) in 1918, global trade resumed and Rolex found that they were sending many watches to the far reaches of the British Empire. The humid tropical climate soon rusted the movements of watches in conventional cases, so a damp proof case was urgently required. In their book "The Best of Time: Rolex Wristwatches: An Unauthorized History", Jeffrey Hess and James Dowling note that Rolex produced a small series of watches using the one piece Borgel screw case in 1922. They remark that "Despite the small number of watches produced in this case style, it is a very important development in Rolex watch design. It was the first model produced by Rolex in which the case was specifically designed to give protection against some of the elements." These Borgel screw case Rolex watches were the start of a line of development which would culminate in 1926 in the Rolex Oyster.

Borgel Cased Watch
Borgel wristwatch

Borgel Cases

In 1891 the Swiss watch case maker François Borgel (1856-1912) patented a case design where instead of having a hinged back cover allowing access to the movement, the normally separate case back and middle part were made in one piece. The movement was mounted in an externally threaded carrier ring, which is attached to the bezel and crystal, and the whole assembly screwed into the one-piece case from the front on a very fine thread. With careful manufacture and assembly the bezel could be made to screw down quite securely against the middle part of the case. The crown was held by a spring against the end of a tube carrying part of the split winding stem, creating a seal, and even the hole in the case for the push-pin for the hand setting mechanism was covered on the inside by a flat steel spring, so these Borgel cases are more waterproof than many people give them credit for. I have taken one (without its movement, just to be on the safe side) and held it under water for a few minutes and it didn't let in water. Not a dive watch maybe, but much better than the standard hinged snap back case of the time. You can read more about Borgel watches on my Borgel page.

To remove the movement of a Borgel cased watch, you first pull out spring loaded crown so that the winding stem is clear of the movement, and then the movement and bezel with the crystal unscrews out of the front of the case in one piece. Because of this, the method of setting the hands is unusual. The crown in its normal position winds the spring as usual, but obviously the pulled-out position is now used to release the movement. To allow setting of the hands, a pin just below the crown is pressed in and the crown then moves the hands. The picture shows a Borgel cased watch with the movement unscrewed from the case. You can see the screw thread on the movement, and the holes where the winding stem and pin-set engage with the movement.

Jean Finger Patent 89276
Jean Finger Patent 89276
Rolex Hermetic
Rolex Hermetic. Image by kind permission
of and © Anthony Green Antiques

The Double Case or Hermetic Watch

In January 1921 Jean Finger, a watch case maker of Longeau, Berne, Switzerland, was granted Swiss patent number CH 89276 for a " Montre à remontoire avec boitier protecteur" literally "a stem winding watch with a protective box".

This design of waterproof watch had the virtue of simplicity, in fact it was brutally simple; the watch was placed inside a larger case with a screw-down bezel which formed an hermetic seal around the watch within. To wind the watch or set the hands the outer bezel was unscrewed and the movement flipped out on a hinge allowing the hands to be set and the watch mainspring wound by a conventional unsealed crown.

Although this case achieved the desired waterproof effect, it had the major drawback that the bezel of the outer case had to be unscrewed every day so that the watch could be wound. Apart from being a nuisance to the owner, the case threads and the milling on the bezel wore quite quickly from this continuous use, so this was a far from ideal solution. However, despite the drawbacks a number of manufacturers including Zenith and Eberhard produced watches using this case design.

It appears that Wilsdorf must have liked the design and bought at least some rights to the patent, because he registered exactly the same case design in Britain on 26 May 1922, which was granted British patent number GB 197208 "Improvements in and Relating to Watches". Wilsdorf doesn't mention Jean Finger in his application, so the exact ownership of the patent is something of a mystery. An identical design had also patented by Frederic Gruen in the USA in 1918, see Double Case "Hermetic" Watches.

A Rolex "hermetic" watch using this case design was produced from 1924. Some hermetic cases bear the words " Double Boitier Brevet 89276" (Double Case Patent 89276), a reference to the Jean Finger patent. Some cases bear the initials JF showing that these were actually made by Jean Finger, but other case manufacturers such as the Borgel company of Geneva also made cases to this design.

Swing Ring or Semi Hermetic

A case design that is sometimes thought to be a variant or development of the Borgel case had a screw on front bezel and no rear opening. The movement is held in a carrier ring hinged to the case and when the bezel is removed the movement can be swung out.

This case design has been attributed to a Francis Baumgartner, but this name is an error based on the conflation of François Borgel and Frédéric Baumgartner due to their common initials of of FB. The semi-hermetic case bears a strong resemblance to one patented in 1924 by Charles Rothen, an employee or associate of Borgel, which you can see on my Borgel Cases page. I have not found definitive evidence of the originator of the semi-hermetic case, it may well have been simply a development of the Rothen case.

Several companies used swing ring cases in the 1920s, including Omega, Longines and Rolex. However, they still were not sealed at the winding stem opening.

These watches are sometimes called "semi-hermetic" because of a superficial resemblance to the Hermetic watch described above, but they are not waterproof; the crown is on the outside of the case and there is no hermetic seal where the stem enters the case. In my view the name semi hermetic is erroneous and misleading, and therefore should not be used.

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The Rolex Oyster

Rolex Oyster
Rolex Oyster.
Image by kind permission of and ©

In late 1926 Rolex launched on to the market a new watch with a waterproof screw-down crown and waterproof case. It was named the "Oyster" by Hans Wilsdorf, he said "because, like its namesake it could remain under water for an unlimited time without detriment."

To what extent was the Rolex Oyster an original Wilsdorf or Rolex design? There had been many previous waterproof watches reaching back as far as the mid nineteenth century, as described on my page Waterproof watches, but none of these had gone on to great commercial success. The Oyster was not the first waterproof watch, or even the first waterproof wristwatch (as was incorrectly claimed in Rolex adverts).

Wilsdorf appears to have been stimulated to create the Oyster by patent CH 114948 for a screw down crown granted to Perregaux and Perret in 1925. It would soon have been realised that the Perregaux and Perret screw crown design was essentially useless, because of the problems with the left hand thread, and it would have been Wilsdorf who cracked the whip to get the technicians at Aegler to come up with a workable design incorporating a clutch, reinventing an idea that had been patented in America in 1881.

The Oyster case was almost certainly inspired by the 1903 Borgel 3 piece screw case, the similarities are obvious and Rolex watches had been made using these Borgel cases, as well as the original Borgel patent screw case.

Although neither the crown or the case were original designs, it was probably Wilsdorf who had the idea of pulling these two ideas together and creating a waterproof watch. Why did the Rolex Oyster achieve commercial success when many earlier waterproof watches, even the war proven 1915 Tavannes Submarine wristwatch, had not?

Wilsdorf was not a watchmaker, he was a marketing genius who was prepared to invest so much on advertising the Rolex name that by the 1920s he had created a known brand from a name that didn't even exist until 1908. The previous designs of waterproof watches were created by watchmakers, and when they were not advertised and promoted they sank without trace. Hans Wilsdorf was a restless marketing genius who really propelled Rolex and the Rolex Oyster, his flagship product, towards the heights it eventually reached. He did this by spending huge amounts of money on advertising.

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The Earliest Oysters

Rolex Oyster 34303
Oyster Case Hallmarked Glasgow 1926 to 1927
Image courtesy of and © Ben Eastwood
Rolex Oyster Registration 1926
Registration of "Oyster" July 1926

The exact date that the Rolex Oyster was "in the stores" and available to purchase is not known. In the Vade Mecum Wilsdorf says "in 1927 the waterproof "Rolex-Oyster" was launched" but many people think that it was on sale in 1926. Wilsdorf acquired the patent that started his quest for a waterproof watch from Perregaux and Perret No 114948 in October 1925 and registered the name "Oyster" in July 1926, as shown by the extract from the Archives de l'Horlogerie shown here.

Dowling and Hess report that they have seen Rolex Oysters bearing the Glasgow Assay Office import hallmarks and the date stamp “d” for 1926/27, and an image of one such case is shown here thanks to Ben. The Glasgow year date letter was changed on July 1 every year when new wardens were elected, so Oysters carrying the Glasgow date letter ”d” were marked at the assay office between 1 July 1926 and 30 June 1927.

The case back shown here is stamped with "Swiss Federal Cross114948", the Swiss Federal cross and number of the Perregaux and Perret patent, and also "Patent applied for". The "Patent applied for" alongside the patent number 114948 is at first puzzling because the official patent number is not known before the patent is granted, so this cannot refer to that patent. It must refer to a patent that been applied for but not yet granted.

The application for a patent on the Oyster case was submitted on 21 September 1926, and was granted as CH 120851 on 16 June 1927. The design of the case was simpler than that of the crown, it simply needed a screw back and bezel, well established technology, and a thread on the pendant for the screw down crown, which a drawing in the patent shows was a right hand thread.

Evidently the design of the screw down crown and clutch mechanism took a little longer. The application for the patent on the screw down crown was lodged on 18 October 1926 and the patent CH 120848 granted on 16 June 1927.

As soon as the designs of the case and the improved screw down crown with clutch had been created, Wilsdorf would have wanted to get watches onto the market. The applications for the patents would have been submitted as soon as the designs were finalised. Inventors cannot reveal their inventions to the public before a patent application is submitted, this would allow someone to claim that the invention was not "original". However, as soon as an application is received at the patent office, its date and time of submission registered. When, and if, a patent is granted, that date becomes the "priority date" from which the period of protection of the invention runs. At the time in Switzerland that protection lasted for fifteen years, so it was in an inventor's interest to get products made and sold as soon as the application was in, rather than allow a year or so to elapse before the patent was granted.

The "patent applied for" legend in the case back must refer to the patents for the Oyster case and screw down crown. This means that the successful design of screw down crown with clutch must have been arrived at in early October 1926. The earliest Oyster watches released for sale must have been shortly after which, together with the dates of use of the Glasgow date letters, gives a range for Oyster watches marked with the Glasgow Assay Office "d" date letter hallmarks of late October 1926 to June 1927.

Early Oyster Serial Numbers

There is a table in the back of the Dowling and Hess book which suggests that, based on hallmark dates, early Oyster case serial numbers followed a linear pattern between 1926 and 1939. In my experience this does not appear to be correct.

There are two potential stumbling blocks with hallmark dates. The hallmark has the force of British law behind it and therefore the date letter will be "correct". However, remember that hallmark date letters span two calendar years, in the case of the Glasgow Assay Office from 1 July to 30 June, and that the hallmark date letter only shows when the case was actually hallmarked, not when the case and a movement were assembled into a watch; that was obviously later - how much later? Who can say — to some extent that must have depended on supply and demand, remember that in the late 1920s there was an terrible economic depression that culminated in the Wall Street crash and subsequent years of slow economic recovery. Expensive watches like the Rolex Oyster would not have been flying off the shelves!

Notwithstanding the hallmark date issues, the serial numbers in the Oyster case backs that I have examined seem to be almost completely random. This may be because Rolex at the time did not have control over what serial numbers were stamped onto the movements by the actual manufacturer, Aegler in the case of the Rolex Oyster. Aegler were supplying many different companies at the time and it appears that Rolex did not have sufficient influence to impose their own serial numbers, they simply had to accept whatever serial number the ébauche manufacturer allocated to the movement.

In later years, from the mid-1930s onwards, Rolex gained more financial influence over Aegler and eventually consumed the whole of Aegler's production, so the serial numbers became more organised.

In short, the serial numbers in early Oyster case backs that I have seen follow no pattern at all and seem to be completely random. If you have a better idea, then please let me know.

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The Screw Down Crown

The part of a watch case that is most difficult to make waterproof is where the winding stem enters the case. Some early designs of waterproof watches, such as the "explorers watches" produced for the Royal Geographical Society in the late nineteenth century overcame this problem by the simple expedient of a cap that enclosed the crown and screwed down onto the case, totally encapsulating the crown and stem, and the hole in the case where the stem entered. This was a bit of a nuisance because the cap had to be removed whenever the watch needed to be wound or set, and there was always the danger of dropping it. An alternative design that made the crown itself function as the cap was invented and patented in the United States by Ezra Fitch around 1880, but this was not a commercial success. You can read about these and other early designs of waterproof watch on my page about The evolution of the waterproof watch.

Perregaux & Perret Patent 114948
Perregaux & Perret Patent 114948

On 30 October 1925 in La Chaux de Fonds, Switzerland, Paul Perregaux and Georges Perret, registered Swiss patent No. 114948 for a winding system where the crown could be screwed down on to the case to create a waterproof seal. The patent was granted and published on 17 May 1926. There seems to be very little known about Perregaux and Perret, who are sometimes described as watchmakers and prototype makers.

1929 Oyster Case Back
1929 Oyster Case Back
Image by permission ©

When Hans Wilsdorf saw this patent, he must have thought he had found the solution he had been searching for. He bought all rights to the patent and had it assigned to him, and then applied for a British patent on 1 September 1926, which was granted as No. 260554 on 21 April 1927. He also patented it in Germany No. 443386, and the United States No. 1,661,232. You can see the Swiss and British patents referenced in the 1929 Oyster case back shown here.

Alongside the British patent number 260554 is stamped the year 1925, the year before the Swiss patent was granted, and before even an application for a British patent was lodged. This is valid because agreements between Britain and Switzerland meant that the application date of the Swiss patent was recognised as the "priority date".

However, although the Perregaux and Perret patent is often referred to as the patent that made the waterproof Oyster possible, not least by Rolex as can be seen from the Oyster case back pictured, it has some serious practical problems that prevented Wilsdorf from putting it into production.

Referring to the figure from the patent reproduced here, it can be seen that the way the Perregaux and Perret design works is as follows: the stem 4 and socket 6 are screwed together so that they are effectively one piece. The crown 8 is coupled to the stem and socket by the two screws 9 and 10 screwed into the crown. The ends of these two screws can slide in the longitudinal grooves 11 and 12 in the socket that I have highlighted in yellow. This permits the crown to move axially with respect to the stem and socket, screws 9 and 10 sliding up or down in the grooves as shown in the difference between figure 1 and figure 2.

Figure 1 shows the crown screwed down onto the case, the two screws are at the bottom of the yellow slots. Figure 2 shows the crown unscrewed from the case and now the screws are at the top of the yellow slots. The socket attached to the stem has not moved outwards with the crown as it unscrews, the two screws have just slid up the yellow slots. However, the two screws ensure that the stem and socket are locked together rotationally: the stem must follow any rotation of the crown and so while the crown is being unscrewed or screwed back down the stem has to turn.

The crown is threaded internally 15 at its lower end, and this thread engages with the thread on the tube 3 that projects from the case. The thread on the tube and the corresponding thread inside the crown are left handed.

This is quite clearly stated in the patent: "The present invention relates to improvements in keyless watches and more particularly to improvements in and connected with the winding mechanism of such watches and is concerned with improvements in that type of winder in which the winder is secured in a moisture proof manner to the pendant or equivalent by means of a left hand screw-thread on the winder engaging a left hand screw-thread on the pendant and then screwed down on the pendant compressing packing means. " (my bold emphasis)

The reason for this is as follows: when the watch needs winding the crown is unscrewed clockwise, in the direction of winding. Once the watch is fully wound, and the hands set if required, then the crown is screwed back down anti-clockwise, which the winding ratchet allows. It can't screw down in the right hand direction because the spring is fully wound, preventing any further rotation of the crown in that direction. The crown has to be screwed down in the direction allowed by the winding ratchet, which is anti-clockwise, or left handed, a very unnatural action!

There are some further undesirable consequences of this design. Once the watch is fully wound and the crown screwed down, the crown cannot be unscrewed until the watch has run down somewhat, because the action of unscrewing the crown also winds the watch, and if it is already fully wound it cannot be wound any further without breaking. So if the owner winds the watch fully, screws the crown down, and then realises that the hands need setting, he is stuck for an hour or two!

Wilsdorf Patent CH 120848

Another poor feature of this design is that the waterproof seal is formed by the base of the crown compressing the gasket 16 against the case, which is in a very exposed position, and would not have lasted long given the gasket materials available in the 1920s; leather, cork or felt.

A Better Design: CH 120848

The Perregaux and Perret design was impractical to say the least, requiring a fair amount of education and care on the part of the customer if disaster was to be avoided. Wilsdorf must have soon realised that this design was not suitable to be released to the public. He put on his thinking cap, or more likely got his "technical assistants" working on it, and by October 1926 they had come up with an improved design. The application for a patent for this was registered by Wilsdorf on 18 October 1926 and the patent was granted on 16 June 1927 as Swiss patent CH 120848, a figure from which is reproduced here.

NAWCC Bulletin, December 2010
Rolex screw down crown and its antecedents.

The clever bit of CH 120848 was that a dog clutch was incorporated into the joint between the stem and the crown, so that the crown could rotate freely while being screwed down and unscrewed from the case, but it became rotationally locked to the stem by the dog clutch when it was clear of the threaded tube on the watch case. This meant that the crown could be could be unscrewed at any time to wind the watch or set the hands, and then screwed down onto the case by a right hand thread that would be familiar to any customer.

Referring to the FIG. 1 from the patent, cylinder 6 is fixed into the crown. The base of this cylinder has a square hole 9 in it which I have ringed in red. The plug 10 screws on to the end of the winding stem, and has a circular flange 11 to centre it within the cylinder 6 and support the spring 13, and a square section 12 at its base which I have also ringed in red.

When the crown is unscrewed from the threaded tube 2, which is fixed into the case wall, it is pushed away from the case by the spring. The square section 12 on the stem end plug drops into the square hole 9 in the base of cylinder 6, and the stem and crown are then locked together rotationally as shown in FIG. 2.

As soon as the crown is pushed back towards the case to screw it down, the cylinder is pressed downwards and the square section on the stem pulls free of the square hole in the base of the cylinder. The crown is then free to rotate and can be screwed down on to the case without turning the stem.

A longer version of this history of the development of the Rolex screw down crown was published in the NAWCC Watch & Clock Bulletin in December 2010, "The Rolex Screw Down Crown and its Antecedents", as shown in the picture above.

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The Waterproof Oyster Case

1929 Oyster Case Back
1929 Oyster Case Back
Image by permission ©

For the Rolex Oyster a new waterproof case was designed and patented. If you look in the case back of an early Rolex Oyster such as the one pictured here you will see four patents listed: two "Great Britain Patents" 260554/1925 and 274789, and below them two "Swiss Patents" 114948 and 120851. These are a British and a Swiss patent for each of two inventions. The first British / Swiss pair (260554 / 114948) were for the waterproof screw down crown; the second pair (274789 / 120851) were for the waterproof Oyster case.

The Oyster case was made waterproof by having a screw back and bezel, and the screw down crown. How the glass was made waterproof in the bezel is not described, but presumably it was simply made a tight fit. The Oyster was not intended to be a dive watch!

An interesting feature of the patent for the case is that it begins by saying that the invention refers to a shaped or "forme" watch case (i.e., different from the usual round or circular form). The patent goes on to illustrate and describe an octagonal case and the means by which such a case can be made watertight. The only reason that I can think of for making the case octagonal shape is to make it more difficult to seal than a round case, and therefore to have something to patent.

Referring to the cross section below, the movement is held in an externally threaded carrier ring 5, which passes through the centre of the shaped case. The front bezel and case back, both numbered 11 in the drawing, screw onto the external threads of this carrier ring, rotating in opposite directions and clamping the middle part of the case between them to form the water tight seal.

Oyster case cross section
Oyster Case Cross Section

The design of the threaded carrier ring is so reminiscent of the screw cases designed by François Borgel that it is not surprising that many people think the Borgel company, then owned by the Taubert family, must have been involved in the design, but no link has yet been proven. In their book on Rolex, Dowling and Hess note that Rolex produced a small series of watches using the original one-piece Borgel screw case in 1922. In fact, the relationship between Borgel and Rolex goes back to way before the 1922 date mentioned by Dowling and Hess. The image here shows a Borgel case with London import hallmarks for 1910 and the W&D sponsor's mark entered by Wilsdorf and Davis.

Borgel case back
Borgel case with London hallmarks for 1910 and W&D mark

The Borgel company also supplied Rolex with three piece 1903 Borgel patent screw cases in the 1920s. The Oyster case was virtually identical to the earlier Borgel design and it seems obvious that the Oyster case was based on the 1903 Borgel design. The question is, why weren't the Oyster cases made by the Borgel company, then in the ownership of the Taubert family?

Wilsdorf was working on the Rolex Oyster in the years before it was revealed in 1926, and the Borgel company was taken over by the Taubert family in 1924, so perhaps Wilsdorf didn't want to approach what was essentially a new company. The Tauberts would also most likely have insisted that their Borgel trademark of the initials FB over a Geneva key to appear in any cases they made, which wouldn't have suited Wilsdorf.

The threaded Oyster case backs were milled with small radial grooves like the edge of a coin to provide the grip needed to tighten and release them by hand, the same as François Borgel had been using on the bezels of his screw cases since 1891. To get a tighter seal than possible by hand tightening in 1926 Wilsdorf designed a tool that engaged with the millings and enabled greater torque to be applied than by hand. On 3 October 1929 Wilsdorf applied for a patent for this tool, which was published on 16 January 1931 under N° CH 143449. The millings on the case backs of modern Rolex watches, and the case openers used today, derive from these early designs.

In the first Oyster case the screw thread on the pendant was cut into a pendant that was made as part of the middle section of the case. If the case was gold or silver, as the vast majority of watch cases were in the 1920s, the threads in these soft metals wore very quickly as the crown was unscrewed every day to wind the watch. This was overcome to a degree by making the pendant a separate steel tube that was harder wearing, and could be replaced if necessary. The problem of thread wear was only really overcome when automatic winding was introduced, which dramatically reduced the number of times that the crown needed to be unscrewed.

Oyster cases accumulated a series of patent numbers inside their backs over the years as listed below. If you know of one I have missed, please let me know!

Who Made the First Rolex Oyster Cases?

Glasgow 1927 to 1928 RWCLtd
RWCLtd, hallmarks Glasgow 1927/28
PdM No. 1 with number 136

Rolex do not reveal information such as the identity of the case maker who supplied the cases for the first Rolex Oysters. However, beginning in the mid 1920s Swiss watch cases of gold and platinum had to be marked to identify the case maker. These marks, called Poinçons de Maître, were very small, and the identity of the maker was encoded, so they are not well known. I am not going to go into this in detail here, you can find more about it on my page about Swiss Poinçons de Maître, but the important point is that these marks can in principle be read to identify the maker of a watch case. The problem is that they are so small they usually can't be read from photographs, at least not at the resolution commonly published on the internet.

Thanks to Crispin at I was able to examine nine high resolution pictures of early Oyster cases. From these I was able to date the cases from the date letter of the British import hallmarks, all impressed by the Glasgow Assay Office, and to read the symbols and numbers of the Poinçons de Maître (PdM). Since then I have also seen a case with Glasgow Assay Office import hallmarks and the date letter "d" for the year 1926 to 1927. All the cases bore the sponsor's mark of "R.W.C.Ltd" inside an oval shield, both the letters and shield being incuse, that is impressed into the plate rather than being in relief or cameo.

The image shows a typical Glasgow Assay Office import hallmark for 1927 to 1928. Reading from the top there is the sponsor's mark R.W.C.Ltd which shows who or what company submitted the item for hallmarking, then below that the sideways "9" and "⋅375" standard mark for nine carat gold, Glasgow Assay Office town mark for imports of two prone and opposed "F"s and finally the date letter "e" for 1927 to 1928. Date letter punches, properly called the ‘assayer's mark’, show who was responsible for the assay and therefore were changed each year when new Wardens were elected. This was part way through the calendar year, so a hallmark date letter refers to parts of two years. For brevity most tables of hallmark date letters show only the first year in which the date letter punch was used. The Glasgow date letter was changed on 1 July each year, so a case with a Glasgow Assay Office date letter ‘d’ was marked between July 1926 and June 1927. There is more about this type of mark on my page at British import hallmarks.

Oyster case hallmarks
All hallmarks Glasgow Assay Office
transfer of patent 114948
Transfer of patent 114948

The hallmarks cover a ten year period from July 1926 to June 1937 and all the cases, except the last, have the Poinçon de Maître of a hammer head bearing the number 136. This shows that they were made by the company of C. R. Spillmann SA of La Chaux de Fonds, later Chêne-Bourg and this shows that C. R. Spillmann SA were the makers of the first Rolex Oyster cases.

The company C.R. Spillmann was involved in the acquisition by Wilsdorf and Rolex of the rights to the Perregaux and Perret patent for the screw crown, CH 114948.

The record from La Fédération Horlogère Suisse shown here records the transfer in October 1925 of the rights to the Perregaux and Perret patent CH 114948, first to C.R. Spillmann et Cie,, and then onwards from Spillmann to Hans Wilsdorf. Together with the Poinçons de Maître from the Oyster cases dating back to 1927 this shows that the Spillmann company not only made the waterproof cases of the first Rolex Oysters but was heavily involved in the design of, and in fact probably were the actual designers of, the waterproof case.

PdM No.2 with number 136

The PdM No. 2 mark of a hammer with handle and the number 136 shown here is in the case of a Rolex Oyster with Glasgow Assay Office import hallmarks for nine carat gold, the date letter "d" for 1926/27. This is interesting because the vast majority of early Rolex Oyster cases that I have seen have PdM No.1, the hammer head. The registrant of PdM No. 2, the hammer with handle, with the number 136 is not recorded in the 1934 list, but given the registration of PdM No. with number 136 to C.R. Spillmann S.A., I think it is safe to say that PdM No. 2 the hammer with handle No. 136 must also have been registered to C.R. Spillmann SA.

In later years C. R. Spillmann S.A. specialised in cases for chronographs, making the cases for all of the early Omega Speedmasters and most of the Rolex Daytonas, until Rolex bought the Spillmann company to bring case production ‘in house’. Thanks to James Dowling for this information.

The company of C.R. Spillmann SA were listed as makers of gold watch case in La Chaux de Fonds. An obituary in La Fédération Horlogère Suisse recorded that Charles-Rodolphe Spillmann died on September 7th 1938. He was the founder and managing director of the company. He was also a founder and member of the executive committee of the Society of Swiss watch case manufacturers. The address given in Spillmann's obituary was La Chaux-de-Fonds, but the 1934 list of PdM gives the company address as Chêne-Bourg. I think that the company of C.R. Spillmann had its headquarters registered in La Chaux-de-Fonds, the building is still there listed as a Swiss heritage site of national significance, with a factory in Chêne-Bourg.

The CR Spillmann SA Poinçon de Maître was cancelled on 5 April 1988, presumably as a result of the takeover of the company by Rolex.

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Advertising Oysters

Once he had a fully waterproof wristwatch in the Rolex Oyster, Wilsdorf was determined to promote it in any way possible and embarked on an extensive and expensive advertising campaign.

On 7 October 1927, Mercedes Gleitze became, at her eighth attempt, the first British woman to swim the channel. She swam from France to England in 15 hours and 15 minutes. Because of a hoax claim (which was soon proven to be false) by Dr. Dorothy Cochrane Logan (using her professional name, Mona McLennan), to have swum the Channel on October 11th in the faster time of thirteen hours and ten minutes, Gleitze's own claim was cast into doubt. To silence the doubters, Gleitze decided to repeat her feat in what became known as "the vindication swim".

Mercedes Gleitze
Mercedes Gleitze

Recognizing a tremendous opportunity to demonstrate the durability of his "Oyster" watch, Wilsdorf offered a new Rolex Oyster watch to Miss Gleitze if she would carry the watch during her swim, to which she agreed. Although it has often been said that she wore the watch "strapped to her wrist", in fact she wore it on a ribbon around her neck. On 21 October at 4:21am Mercedes Gleitze once again entered the water at Cap Gris Nez. But this time the water was much colder, and she was unable to complete the crossing. At 2:45pm, after swimming for 10 hours and 24 minutes, she was pulled semi-conscious from the water some seven miles short of the English shore.

Gleitze Channel Swim
The Times, Oct 22, 1927

Although she did not complete the second crossing, a journalist for The Times of London wrote "Having regard to the general conditions, the endurance of Miss Gleitze surprised the doctors, journalists, and experts who were present, for it seemed unlikely that she would be able to withstand the cold for so long. It was a good performance." This silenced the doubters, and Mercedes Gleitze was hailed as a heroine.

As she sat in the boat, The Times' journalist made a discovery and reported it as follows: "Hanging round her neck by a ribbon on this swim, Miss Gleitze carried a small gold watch, which was found this evening to have kept good time throughout." When examined closely, the Oyster watch was found to be in perfect condition, dry inside and ticking away as if nothing had happened.

1930 Punch Advert
1930 Rolex advert in Punch

One month later, on 24th November 1927, Wilsdorf launched the Rolex Oyster watch in the United Kingdom as the focal point of a full front page Rolex advert in the Daily Mail, and the Rolex Oyster began its rise to fame.

Old Bond Street House
6-8, Old Bond Street
London, W.1.
13th May 1930

Dear Sirs.

I have now been using my Rolex Watch for some little while, and it is keeping perfect time under somewhat strenuous conditions.

I was wearing it on the occasion of the J.C.C. Double 12 Hours Race on Friday and Saturday last, and the vibration which this watch had to withstand during this long period has not upset its time-keeping properties in the least.

I would like to congratulate you on having produced a very first-class Watch, suitable for really rough treatment.

Yours faithfully, Malcolm Campbell

Wilsdorf also co-opted various sporting personalities into endorsing the Oyster. This advert appeared in Punch on the 18 June 1930. In it is reproduced a letter from Captain Malcolm Campbell (he was knighted as Sir Malcolm Campbell in 1931).

Note that although Campbell says that the watch is suitable for really rough treatment this was still before the widespread use of shock protection jewel settings for the balance staff pivots, so a sharp blow could, and still can, break the balance staff pivots on one of these watches, so don't take Campbell too literally.

In another marketing coup, in 1935 a Rolex Oyster went over 300 miles per hour on the wrist of Sir Malcolm Campbell as he set the world land-speed record in his race car at Salt Lake Flats.

The investment of a watch in Miss Gleitze's attempt proved a typically shrewd move by Wilsdorf, and Rolex were still using the event in adverts into the 1950s. The advert below left from Punch in August 1950 states that the Rolex Oyster was the first waterproof wristwatch in the world, which is not strictly true, there were other waterproof wristwatches made before the Rolex Oyster, but it was the first that was advertised to a mass audience through an extensive advertising campaign, Wilsdorf's forté.

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The Rolex Perpetual

Now that the problem of water-proofing had been solved, there was just one small remaining issue; namely, that the owner had to unscrew the crown each day in order to wind the watch. There were two side effects of this; (1) sooner or later the owner would forget to screw the crown down tightly again and the watch would no longer be hermetically sealed, and (2)in time the waterproof seals or the threads would wear out, and the same result ensue. This was solved by Rolex in 1931, with the introduction of the "Perpetual" self-winding movement.

The concept of a self-winding watch had first been introduced in 1770s. For many years it was generally believed that the rotor self winding mechanism was invented by the Swiss watchmaker Abraham-Louis Perrelet, but information uncovered by Richards Watkins includes a report from 1778 that is a clear indication that it was Hubert Sarton, of Liège in Belgium who invented the rotor wound watch.

However, Perrelet independently designed a self-winding watch at the end of 1775 or at the beginning of 1776. The winding mechanism worked on the same principle as a pedometer, using an reciprocating weight inside the watch that moved up and down as the owner walked, which through a set of gears wound the mainspring. Perrelet was the first person to create a working, practical mechanism.

The Parisian clock and watchmaker Abraham-Louis Bréguet improved the mechanism in his own version, calling his watches "perpetuelles"; the French word for perpetual, and possibly the source of Rolex's name for its "Perpetual" automatic or self winding movements.

1950 Punch Advert
1950 Rolex Advert in Punch

The first self winding wristwatch was invented in 1923 by a watch repairer from the Isle of Man named John Harwood. He took out a UK patent with his financial backer, Harry Cutts from Cheshire, on 7 July 1923, and a corresponding Swiss patent on 16 October 1923. The Harwood system used a semi circular weight that pivoted at the centre of the movement and swung through a 300 degree arc as the wearer moved his wrist or arm, and through a train of gears wound the mainspring. This was called a "bumper" design because the weight ran into a spring bumper at the end of its 300 degree travel, which the wearer could feel. When fully wound, the watch would run for 12 hours. It did not have a conventional stem winder, so the hands were moved manually by rotating a bezel around the face of the watch.

Harwood formed the Harwood Self-Winding Watch Company and commissioned the Swiss firms Fortis and A. Schild to make the watches using the Adolf Schild Calibre Cal. 350 as the base movement. The watches went on sale in 1928. They were not a runaway success in the market, and only some 30,000 were made in total. However, the presence of the patent meant that from 1923 no one else could develop a similar or improved version, so progress was essentially halted at a time when the wristwatch was becoming more and more popular. The Harwood company collapsed in 1931 during the Great Depression and, although the patent still existed, there was no one to exercise it so other companies were free to develop their own versions.

Emile Borer, nephew and ultimately successor to Hermann Aegler and head of research and development at the Aegler Bienne factory, took up the Harwood design and used it as the basis for a self winding mechanism. He improved on Harwood's design so that the centrally mounted semi-circular weight became a rotor which could rotate smoothly through a full 360 degrees and was able to turn both clockwise and counter clockwise, rather than running the 300 degrees and then hitting the bumpers of the Harwood design. This improved its performance, durability, and feel for the wearer, although it only actually wound in one direction. The amount of energy stored in the mainspring was increased, allowing the watch to run autonomously for up to 35 hours. Felsa introduced the patented 410 calibre "Bidynator" (bi-directional winding) in 1942; Aegler did not produce a bi-directional automatic winding movement until 1950 with the calibre 1030.

As a result of automatic winding it was no longer necessary to manually wind the watch every day, and the crown was used principally to set the time. As this did not require doing often, due to the accuracy of the watch, the waterproof seal was only disturbed occasionally and there was much less wear in the threads or likelihood of forgetting to screw the crown down. Consequently, Rolex Oyster Perpetual watches were now not only accurate but also durable. The automatically wound watch was even more accurate than the hand wound version because the tension put on the mainspring by constant automatic winding whilst the watch was worn was more even than that provided by winding once a day.

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Copyright © David Boettcher 2006 - 2019 all rights reserved. This page updated September 2019. W3CMVS.