RolexCopyright © Notice
The story of the Rolex watch is inextricably entwined with the story of Hans Wilsdorf, who 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 others contributed, and there were waterproof and self winding watches before the Rolex Oyster, but the fact remains than Wilsdorf is the central figure in the story of the modern mechanical wristwatch.
This 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, and was printed in a limited edition of 1,000. The booklets are:
- Step By Step
- The Evolution Of The Wrist Watch Chronometer
- How The Waterproof Watch Came Into Being
- The Story of the Self-Winding Watch
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!
If you have any questions, suggestions, or comments, then please drop me a line at Please don't give out my email address, refer anyone interested to this web site. I try to answer all emails I receive so if you don't get a reply in a few days please check your junk or spam folders.
Hans Wilsdorf - Early Days
Hans Wilsdorf was born in Kulmbach, Bavaria, Franconia (Germany) on March 22, 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 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, he started work at the major clock and watch exporting firm Cuno Korten in La Chaux de Fonds, Switzerland, for a wage of 80 Francs per annum, and became their English language correspondent and clerk. La Chaux de Fonds, along with Geneva, formed the hub of the high-quality watchmaking industry at the time. There, Wilsdorf was exposed to the most influential people and practices in watchmaking, which would later be an important asset in the founding and success of Rolex. In 1903 Wilsdorf moved to London to work for another watch making firm. Growing in confidence with the experience he gained from this and his previous employment, he set about establishing his own firm.
Foundation of Wilsdorf & Davis
In 1903 Wilsdorf moved to London, where he worked for a large watch store. Two years later, 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. Their first speciality was a travelling watch, called a portfolio watch cased in fine quality leather. But Wilsdorf was convinced that the wristwatch was the way of the future. In 1902 while in La Chaux de Fonds, he had become aquainted with the firm of Hermann Aegler in 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 pioneered by Aegler, making extensive use of machinery so that parts were interchangeable.
In 1905 Wilsdorf went to Bienne and agreed with Hermann Aegler for the firm to manufacture wristwatch movements to Wilsdorf's specification, and placed the largest order for wristwatches ever seen at that time. The first wristwatches produced under this arrangement were mens and ladies in silver cases with leather straps. Their immediate success after the autumn launch prompted Wilsdorf to introduce a selection of designs in gold cases. In 1906 the expanding bracelet was launched by an important jewellery firm, and Wilsdorf immediately made this available as a very popular option on his watches.
W&D: Wilsdorf and Davis punch
Registration with the London Assay Office
To send items for assay and hallmarking it was necessary for details to be registered with the assay office, including a UK address and the mark made by a punch used to identify each item that was sent in. This W&D is the sponsor's mark of Wilsdorf & Davis, recorded in the register as importers of gold and silver wares, first registered at the London Assay Office on 25 June 1907. A second punch with the same mark was registered on 13 August.
Until 1907 Wilsdorf & Davis imported watches and other silver and gold items without having them tested and hallmarked by a UK assay office, but UK law changed in 1907 and from 1 June 1907 all imported gold and silver items had to be assayed and hallmarked at a UK assay office. This is the reason for the registration of the W&D sponsor's mark. Items imported from Switzerland by Wilsdorf & Davis before 1907 would have carried Swiss hallmarks. Once the UK law was changed, the Swiss authorities allowed items to be exported to the UK without Swiss hallmarks.
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 two men working full time punching items that were to be sent for hallmarking.
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.
Aegler supplied Wilsdorf & Davis with movements manufactured in its ebauche factory in the Rebberg district of Bienne and hence these early movements are often referred to as "Rebberg" movements, even if they are not stamped with the Rebberg name. Rebberg was a registered trade mark of Aegler.
Wilsdorf had the movements supplied by Aegler fitted into cases in Switzerland, or sometimes in England by the Birmingham case maker Dennison. Aaron Lufkin Dennison (1812-1895) had pioneered mass production watch making in the USA, but ran into financial difficulties in a turbulent financial period in 1857. In 1862 he moved to England and set up the Dennison Watch Case Co. of Birmingham. Watch cases supplied to Wilsdorf & Davis were usually stamped "Dennison Watch Case Co" but Dennison also used the case maker mark "ALD" for Aaron Lufkin Dennison. It seems that Wilsdorf & Davis imported watches already cased in silver cases, but that it was better economically to have the expensive gold cases made in Britain and then the movements put into them in the UK to avoid the high import taxes on the gold.
The Birth of the Rolex Brand
In 1907 Wilsdorf opened an office in La Chaux de Fonds for marketing wristwatches, and coined the name Rolex. Some have speculated that this was 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". But he doesn't reveal where the name came from, so we shall probably never know. His description of the way the word is short, easy to remember and pronounce echos the words of George Eastman, who registered the trademark Kodak on 4th September 1888. Eastman said his criteria for 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 this in mind when he devised the name Rolex.
First registration of the Rolex name
Wilsdorf registered Rolex as a brand name in Chaux de Fonds on 2nd July 1908 as shown in the registration to the left. 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, and also supplied movements to Gruen. Aegler registered Rolex as a trade name in 1913 for the manufacture of watches and watch parts.
At first the Rolex name was stamped or engraved on the case and movement only; the dial being left free for the retailer to apply their name. Rolex was then a new and unknown name, whilst most of the stores they supplied had been in business for a long time, so naturally people would have more faith in a watch with the name of "The Goldsmiths Company" or "Asprey" on the dial, rather than the unknown Rolex.
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 calibers for chronometer tests. The ability of a wristwatch to maintain accurate time keeping could no longer be doubted.
The Great War
With the outbreak of the Great War (World War One or WW1), soldiers wanted reliable and accurate wristwatches and, as they were not issued with them as standard equipment, they bought their own. This presented an opportunity for Wilsdorf to sell more wristwatches, but the war also led directly to some serious problems. In 1915 the British Government imposed an ad valorem duty of 33.⅓% on imported luxuries, including clocks and watches, to conserve foreign currency reserves as part of the war effort. This meant that any watches imported into London, even if only for checking with subsequent export abroad, would be subject to this high rate of tax. To avoid paying this tax on watches not destined for the British market, Wilsdorf moved his Swiss office from La Chaux de Fonds into the Aegler factory and expanded its function 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.
In 1919 Wilsdorf decided to relocate the headquarters of Rolex from London to Geneva. 1919 also witnessed another major development in the history of Rolex when Wilsdorf and Davis gave nearly 15% of equity in their company to Herman Aegler. With this exchange, Aegler became the sole supplier of movements to Rolex and in exchange the company's name was changed to Aegler S.A. Rolex Watch Co.
My Grandparents' Rolexes
In 1918 my grandfather purchased a pair of Rolex watches for himself and my grandmother. You can see them in the photograph below, and then the dial, movement and inside case back of my grandfather's watch. The dials are very easy to read. My grandfather's watch in particular has a beautifully simple design; sharp black arabic numerals on a crisp white enamel background, the 12 being picked out in red. The hands are elegant and perfectly proportioned, the minute hand being a slender baton and the shorter hour hand a lunette style. Note that the crown is made from gold, a harder material than silver, to withstand the rigours of winding every day. 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.
On the 13 ligne Rebberg movement of my grandfather's watch you can see that 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”.
The movement of my grandmother's watch is eactly the same as my grandfather's watch but 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 itesm, and a date letter “s”for 1917/1918. The Rebberg movement was evidently imported from Switzerland but cased in England, to avoid the high import duty mentioned above.
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 33.⅓% on imported luxuries evidently did not make it worthwhile to use English silver cases, but it was worthwhile when for gold cases.
A Note on Hallmarks
The easiest way to distinguish a hallmark struck on an imported watch after 1 June 1907 is to look at the town mark, the symbol that shows which assay office carried out the assay and hallmarking. In my grandfather's watch the town mark is the sign of leo on a crossed back ground in an oval shield. This was used by the London Assay Office on imported watch cases, for watch cases manufactured in the UK the London Assay Office would have used its traditional town mark of a leopard's head. In my grandmother's watch case, the town mark is the anchor used by the Birmingham Assay Office on items manufactured in the UK. For imported items, the Birmingham Assay Office used the town mark of an equilateral triangle. Had my grandmother's watch case been made of sterling silver in the UK, the traditional lion passant or walking lion with raised right forepaw would have been used to indicate the standard. The use of the lion of sterling silver on imported watch cases was made illegal in 1888.
London hallmark dates around the date of the first world war are easy to remember. They started in 1896 at "a" running in sequence to " u" in 1915, missing out "j" in 1905. They then started again with "a" in 1916, the year of the battle of the Somme, a pivotal event in British history. If you remember 1916, battle of the Somme, letter "a" and the year before, 1915 letter "u" then it is quite easy to work out what is the date of any London hallmark date letter around the time of the Great War.
There is much more about hallmarks and date letters on the pages beginning with my Casemarks page.
The Rise of the Rolex Brand
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!
Early 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, but he was by far the most commercially successful.
Borgel Cased Watch
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 miutes 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. In the early 1920s Rolex used Borgel cases to improve the dust and moisture resistance of their watches, which marked the start of a quest that culminated eventually in the Rolex Oyster.
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.
Screw Back and Bezel
An alternative design was based on a standard pocket watch case. This involved taking the middle part of the case and threading it on both sides, rotating in opposite directions. The movement and dial were then mounted in the middle part of the case, and the case back and bezel screwed on from the back and the front. Because the orientation of the movement was not affected by the screwing on of the back or bezel, the bezel and case back could be screwed down tight and a hermetic seal achieved.
Watches with screw back and screw bezel cases were in use in America in the 1870s, and in Europe Alcide Droz & Fils patented a watch with a screw back and bezel case, and a screw down crown, which they called "l'Imperméable" in 1883. The first British military wristwatches officially issued in 1917 had this type of case - see my history page. But although the screw back and bezel solved the problem of the case joints, it did not address the opening in the case for the winding stem.
Another apparant attempt to improving watch case sealing was the swing ring case, sometimes called the "Semi-Hermetic". This had a one piece case with no separate back. The movement was carried in a ring hinged to the case, which had a slot cut in its side to accommodate the winding stem. The bezel screwed down to secure the movement in the case.
The "Semi-Hermetic" name seems to have come from the superficial resemblance of these cases to the Rolex Hermetic watch discussed below. However, the design was in use much earlier than this, particularly in American pocket watches, when it was called a "swing ring" case because of the hinged ring which carried the movement and which could be swung out of the case. There was no attempt to seal the entry point for the winding stem, and the term "Semi-Hermetic" is rather a misnomer.
Jean Finger Patent 89276
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.
Rolex Hermetic. Image by kind permission
of and © Anthony Green Antiques
The Double Case or Hermetic
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 watch with a protective box". The watch was placed inside a larger case which had a screw-down bezel, forming an hermetic seal and totally protecting the watch within. Once the bezel was unscrewed, the flipped out on a hinge to allow the hands to be set and the movement wound.
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 the rights to the patent, because he registered exactly the same case design on May 26 1922 under British patent GB 197208 "Improvements in and Relating to Watches". A Rolex watch using this case design was produced from 1924, and similar designs from other manufacturers disappeared. 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 and these were actually made by Jean Finger.
Perregaux & Perret Patent 114948
Invention of the Rolex Screw Down Crown
On October 30th 1925 in La Chaux de Fonds, Paul Perregaux and Georges Perret, registered Swiss patent No. 114948 for a moisture proof winding system, where the crown was screwed down to create a waterproof seal. This patent was published on 17th May 1926. There seems to be nothing known about these two individuals, described variously as watchmakers and prototype makers.
1929 Oyster Case Back
Image by kind permission of and ©
When 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 registered it as British patent No. 260554 on September 1st 1926. The British patent was published on April 21st 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 this 1929 Oyster case back, where Wilsdorf has used a bit of "artistic licence" to show the original Swiss registration date of 1925 alongside the British patent number.
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, which I believe prevented Wilsdorf from ever putting it into production.
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 connected to the stem and socket by the two screws 9 and 10. These screws can slide in the longitudinal grooves 11 and 12. This permits the crown to move axially with respect to the stem and socket, screws 9 and 10 sliding in the grooves as shown in the difference between figure 1 and figure 2. But the screws ensure that the stem and socket are locked together rotationally: the stem must follow any rotation of the crown.
The screw thread on the tube 3 that projects from the case, and the corresponding thread on the inside of the crown are left handed. 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, against winding the ratchet.
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 the left hand thread is because once the watch is fully wound, the crown can no longer be turned clockwise as would be required by a right hand thread, so the thread must be left handed. 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!
Another poor feature of this patent is that the waterproof seal is formed by 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.
Wilsdorf Patent CH 120848
This 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 realised that this design was not suitable to be released to the public. Wilsdorf put on his thinking cap, or more likely got the design engineers at Aegler working on it, and by October 1926 they had come up with an improved design. The patent for this was registered on 18th October 1926 as Swiss patent CH 120848.
The clever bit of CH 120848 was that a 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 became rigidly locked to the stem when it was clear of the threaded tube on the watch case. This allowed the crown to be screwed down by a right hand thread that should be familiar to any customer, and meant that the crown could be safely unscrewed at any time to wind the watch or set the hands.
Referring to the figures from the patent, cylinder 6 is screwed into the crown. The base of this cylinder has a square hole 9 in it. A 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.
When the crown is unscrewed from, and pushed away by the spring from, the threaded tube 2, which is fixed into the case wall, 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 soon as the crown is pushed back towards the case to screw it down, the square section on the stem pulls free of the square hole in the base of the cylinder, and the crown is free to rotate and be screwed down without turning the stem.
Rolex Oyster. Image by kind permission
of and © OldeTimers.com
The Oyster Case
The first "Oyster" watch (named Oyster by Hans Wilsdorf because like its namesake it could remain under water for an unlimited time without detriment) was introduced in late 1926. Now that he had a wristwatch unlike any other, Wilsdorf was determined to promote it in any way possible.
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 was called "the vindication swim".
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 October 21st 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 she was pulled semi-conscious from the water after 10 hours and 24 minutes, some seven miles short of the English shore.
The Times, Oct 22, 1927
Although she did not complete the second crossing, a journalist for the London Times 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 same journalist made a discovery and reported it as follows: "Hanging round her neck by a riband 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 watch was found to be in perfect condition, dry inside and ticking away as if nothing had happened.
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.
1930 Rolex advert in Punch
Wilsdorf also coopted 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).
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.
Who made the cases of the first Rolex Oysters?
Rolex do not reveal information like this, but beginning in the mid 1920s Swiss watch cases of gold and platinum had to be marked to identify the 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 Case Marks page, but the important point is that these marks can in principle be read to identify the maker of the 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 Oldetimers I have been able to examine nine high resolution pictures of early Oyster cases. From these I have been able to date the cases from the hallmarks, all Glasgow, and get the numbers of the Poinçons de Maître. They all, except the last, have the Poinçons 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 Chène-Bourg and indicates 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 Rolex of the rights to the Perregaux and Perret patent for the screw crown, CH 114948. They first purchased the rights to the patent from Perregaux and Perret and then sold them on to Hans Wilsdorf.
The Self Winding 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 1770 by the Swiss watchmaker Abraham-Louis Perrelet for pocket watches. It worked on the same principle as a pedometer using an oscillating weight inside the watch that moved up and down as the owner walked, which through a set of gears wound the mainspring. Perrelet sold some of his watches to the Parisian clock and watchmaker Abraham-Louis Bréguet who 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 automatic movements.
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 only 12 hours, which was obviously a serious drawback. It did not have a conventional stem winder, so the hands were moved manually by rotating a bezel around the face of the watch.
They 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, son in law of the Aegler family and head of research and development at the Rolex Bienne factory, took up the Harwood design and used it as the basis for the "auto rotor" of the Rolex caliber 620 Oyster Perpetual. He improved the 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 Rolex version also increased the amount of energy stored in the mainspring, allowing it to run autonomously for up to 35 hours. Felsa introduced the patented 410 caliber "Bidynator" (bi-directional winding) in 1942; Rolex did not produce a bi-directional automatic winding movement until 1950 with the caliber 1030.
As a result of automatic winding it was no longer necessary to manually wind the watch every day, and the crown was used solely 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 likelihood of wear or 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 winding whilst the watch was worn was more even than that provided by winding once a day.
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.
Rolexes with Calendars
In 1945, Rolex recorded another highly important patent: a small window was added to the dial at the 3 o'clock position, and a numbered wheel under the dial was moved on at midnight by the mechanism so that the watch showed the date as well as the time. This model was introduced as the "Datejust" and it became an immediate best-seller. It was followed in the early 1950s by the " President" - a man's wristwatch that has a window at 12 o'clock which displays the day of the week. Still not quite as good as the 1901 Goldsmiths watch we met on the history page, with its perpetual calendar showing day, date and month, and the moon phase dial, but not bad for a wristwatch!
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