Dials and Hands

Copyright © David Boettcher 2005 - 2023 all rights reserved.

The dial plate and the hands which move around above it to indicate the time are the most important parts of the "face" of a watch. They give it its function, and also its beauty.

Watch dials can be divided broadly into two groups; classical and modern. Classical watch dials were sometimes made of metal, but when the technique of making enamel dials was developed in the eighteenth century, the intrinsic beauty of the smooth and clear white or cream finish became the favoured material for the next two hundred years. However, enamel dials are difficult and expensive to make, so in the mid-twentieth century dials that were simply painted or lacquered came into fashion. These painted dials were not only much cheaper than enamel dials, but allowed much more freedom of design so that brand names, logos and colours could be more easily used.

It is important to understand how dials were made and which type of dial you are dealing with, because this affects how they can be cleaned or restored. For example, vitreous enamel dials are incredibly durable and will happily go through a hot wash in an ultrasonic tank and look all the better for it, but they can easily be cracked if even slightly bent. On the other hand, metal dials with painted finishes will bend without problems, but their surface is very delicate. It frequently deteriorates over time, discolouring or flaking, which is a problem because the delicate paint or lacquer finish can be destroyed by even gentle cleaning; if you put a painted dial through a hot wash in an ultrasonic tank, all that comes out is a blank metal plate!

To collectors of modern watches, the fragility of painted dials is a problem. Simply age or sunlight can discolour or cause the paint to crack, and if any moisture has got into the case, or too much oil has been applied to the movement, and has got to the dial, this can also damage the paint. The only way to repair such damage is to strip off the paint and repaint the dial - a “redial”. There are a number of companies who specialise in doing this, a quick internet search for “dial refinish” will return a list. Many modern watches have undergone this treatment. Although the improvement in appearance can be dramatic, the loss of originality often has a major affect on the value of the watch.

Collectors of watches with enamel dials are in a different, perhaps better, position. There is really no such thing as a redial of an enamel dial. Unless the enamel is badly cracked, a simple wash brings it up perfectly clean and as new, and can even make hairline cracks virtually invisible. If the dial had luminous paint on it, which originally would have been radioactive radium paint on an enamel dial, then this can be cleaned off and replaced, which is described as “re-luming” a dial rather than refinishing it. Radium luminous paint was usually replaced every few years because it stopped glowing.

It is also important to understand what type or style of hands go with what type of dial, so that the harmonious appearance of the two is preserved. Failure to appreciate this is most often seen when a dial with skeleton numerals for luminous paint has been fitted with plain instead of skeleton hands. There would not be much point in being able to see the numerals in the dark if you couldn't see where the hands were pointing!

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Enamel Dials

The very first watch dials were made of metal. In the eighteenth century, the process of using vitreous enamel to make high quality dials with white, cream, or sometimes black, backgrounds, with hour numbers, minute tracks and other other details in vitreous ink, was developed.

The word “enamel” refers to any hard shiny coating such as tooth enamel, enamel paint, or even nail enamel (nail varnish). However, when used in the context of watch dials, enamel refers to an opaque or semi-transparent hard, glass like, surface applied to a metal dial plate by vitrification. Vitrification (from Latin vitreum (glass) via French vitrifier) is the transformation by melting of a substance into a glass. The full name of the substance used for watch dials is vitreous enamel.

Vitreous enamel dials have a very hard surface which is usually shiny and reflective like glass, but the surface can be made matt by rubbing with abrasive after firing.

Vitreous enamel is made from powdered glass. Tin oxide is added to make it opaque white, other chemicals are used for other colours. To make a dial the enamel is fused onto a copper dial plate by firing in an oven at high temperature, melting the glass and causing it to run together to produce a smooth glassy surface. First the overall white or black background is made, which might take four rounds of firing and smoothing to get the desired finish. Then the numbers and tracks are drawn on in black or white enamel ink, which is then also fired, at a lower temperature, to fix it to the white background.

After firing, vitreous enamel is invulnerable to ageing or fading and can be easily cleaned; an enamel dial will happily go through an ultrasonic clean. Vitreous enamel will be cracked if the dial is flexed, e.g. by being handled clumsily or levered off from the movement without releasing them first, but apart from this kind of physical damage they will last forever.

Enamel dials are expensive to make, so in the twentieth century cheaper materials were used, usually by printing the details onto a metal base and then covering with clear lacquer. Such dials are prone to discolouration, fading, and spotting, but are are extremely delicate and cannot be satisfactorily be cleaned.

To make an enamel dial, a sheet of copper is cut to the correct size and shape, with holes for the hand arbors, and "dial feet" attached to its underside. Dial feet are small copper rods attached to the underside of the dial, usually by welding or soldering. They enter holes in the movement bottom plate, where they and are gripped by screws or clips. Over tightening the dial feet screws is a frequent cause of distortion to the dial plate, causing the enamel to crack.

In manufacture, the copper dial plate is coated with crushed and finely powdered glass. It is then heated in a furnace to about 800°C until the powder melts and becomes liquid, bonding to the copper and fusing together to form a coating of glass with a smooth glassy surface. This process is usually repeated several times, with the dial being cleaned and rubbed down between each layer, to get a perfectly smooth and opaque surface.

The numerals and minute and seconds tracks are then added in vitreous painting enamel, sometimes called vitreous ink, either hand painted or transferred with a stamp, and the dial is fired again. This melts the enamel of the numbers and other details and bonds them into to the base layer of enamel. In the cross section I have shown a white enamel dial with red ink on it, say a red number 12. When the enamel of the numbers and other details melts and bonds with the underlying enamel it becomes virtually flat with the dial surface as the cross section shows. The numbers and tracks become as much a part of the dial as the underlying enamel and cannot be removed.

Initially the numbers and tracks were painted by hand, but later an engraved copper block was used. The engravings were filled with vitreous ink and a gelatine pad used to pick up the ink and stamp it onto the dial. In this way many dials could be made accurately and quickly.

Enamel Paint

The drawing of an enamel dial cross section shows how enamel paint can be added to a vitreous enamel dial. Unlike the vitreous ink used to make the markings and numerals on the dial, the enamel paint cannot be fired - the paint would just burn. This means that the enamel paint does not form a strong bond with the underlying vitreous enamel, it just sits proud of its surface as shown in the drawing.

Enamel paint was often used to add a British retailer's name to an enamel dials of watches that were imported into Britain before the mid 1920s. Before the mid 1920s British retailers would not buy watches with a manufacturer's names or brand on their dials. If there was any name on the dial, it was that of the retailer. A small number of retailers were large and important enough to have their names or brands put onto dials in fired vitreous ink as they were made, but most did not, so enamel paint was used.

This means that Rolex, Longines, Omega, etc. watches sold in Britain before the mid 1920s didn't have their brand on the dial, and sometimes there was no name to be found anywhere. Nowadays most people expect to see a name on the dial, so some unscrupulous people have names painted on to make the watch more saleable (read "valuable"). It looks wrong.

Rolex is the most faked watch brand, so this addition of a name onto a dial in enamel paint happens most often with the Rolex name. Needless to say, just painting Rolex onto a dial does not really transform a watch into a Rolex watch. Sometimes the name is added to a genuine Rolex watch because the owner expects to see it there, but often watches that were never Rolex watches in the first place receive a new name. This is what has happened with the dial of a Marconi watch shown in the image here. If you enlarge it you can see the shiny new enamel paint on the surface of the vitreous enamel dial. It is obvious that this had been painted on quite recently.

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, enamel paint is nothing like as durable as the vitreous enamel of the dial itself. Unlike vitreous enamel, enamel paint can be easily dissolved by a solvent such as acetone or isopropyl alcohol.

Unlike the fired vitreous ink of the numerals and tracks, enamel paint doesn't bond into the underlying vitreous enamel but remains on its surface. It can usually be easily distinguished from the fired numbers and tracks by looking obliquely across the dial with a lens when it can be seen standing proud of the surface as illustrated. Because the vitreous enamel of the dial is very shiny, enamel paint has difficulty sticking to it and the added names have often become badly worn, or disappeared altogether.

If you look carefully at a vitreous enamel dial and detect that a name has been added in enamel paint, but the name doesn't show any signs of ageing, chipping or flaking, then it is quite likely that the name has been added recently.

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Names on the Dial

Throughout the nineteenth and early twentieth centuries, with very few exceptions, British retailers only allowed their own names onto the dials of watches they sold. The concept of a “brand”, which would conflict with the retailer's identity and reputation, was fiercely resisted. If there was to be any name on the dial, British retailers wanted it to be their own name. It was not until the late 1920s that British retailers began to accepted Swiss manufacturer's names on the dials of the watches they sold, a move largely forced on them by Hans Wilsdorf's extensive advertising of Rolex branded watches.

Watches are often seen with the names of prominent retailers of the period such as Harrods, Asprey, Hamilton & Inches, Finnigans, etc., etc. These names are almost damaged to some degree, whereas the rest of the numbers and markings on the dial are still pristine. This is because the name was painted in enmel paint onto the fired vitreous enamel dial. The fired enamel dial is hard and shiny and the enamel paint does not stick well to it, so bits drop off over the years.

This is clearly demonstrated by my grandfather's and grandmother's Rolex wristwatches. Although the Rolex name is engraved onto the movements and stamped in the case back of both watches, the dials are completely plain. These watches have been in my family since they were purchased new and have never been altered, so I know that the dials have always been plain like this.

Brand names were invented in the nineteenth century for food, to give people confidence in the purity of products. The idea soon spread to other areas, such as Kodak for film and cameras. In other countries in Europe and around the world, brand names played an important role in selling watches, but in Britain retailers stubbornly refused to entertain the idea. In the twentieth century some English watch manufacturers began to brand their watches. One of these was H. Williamson Ltd. who trademarked the name “Astral” and began to put this onto the dials of their watches around 1910.

This didn't meet with universal approval. Speaking in an interview in 1933, Mr R. E. Tucker, who had been a director at Williamsons, attributed this to the attitude of British retailers, who wanted to put their own name on the watches that they sold. Writing in the Horological Journal in 1916, Thomas Field, Managing Director, Field & Son, Ltd., Aylesbury, complained about “cheap, trashy American, Swiss and German "branded" watches” and stated “Speaking for my own firm, we have on principle never sold a "branded" watch of any description excepting those carrying the name of "Field & Son, Aylesbury."”

High end British retailers remained stubbornly resistant to the names of foreign manufacturers appearing on the dials of watches. This only changed in the late 1920s, when Hans Wilsdorf started to advertise the Rolex brand extensively in Britain, and people started asking for Rolex watches.

Wilsdorf said that when the Rolex Oyster was launched in 1927, he made the decision to insist that all Rolex watches carried the brand name on the dial. British retailers were suddenly faced with customers who had read about Rolex watches in the newspapers, and seen adverts for them, and started asking for Rolex watches by name. The retailers had no choice; they had to start stocking watches with the manufacturer's name and brand on them, or their rivals would and they would lose out. This was the start of a trend and other watch manufacturers soon followed.

In December 1927 the British Watch and Clockmakers' Guild held an open meeting to discuss “Pros and Cons of the Branded Article”. Hugh Rotherham kicked off the debate by saying that “in England watchmakers and jewellers insist, or most of them insist, on selling English watches with their own names on, and the public do not to-day, as a rule, look on the name as a guarantee of manufacture but as a guarantee of quality;” but noted that in Australia, New Zealand, India, Straits Settlements and South Africa, English manufactures would not sell a watch that had not got the manufacturer's name on it. A letter from the editor of the National Association of Goldsmiths Journal was read out, stating “I am afraid you will find no one in particular opposition to the branded watch except some very out-of-date retailers.” Mr. G. E. Limmer said that there was not a single watch sold in America without a brand on the dial. Mr. Charles Tucker pointed out that a branded article had to be advertised very extensively to be successful, costing between £25,000 and £30,000 a year, which was possible in America where there was an enormous market, but he questioned who would pay for this in Britain. The Secretary reported that Messrs. J. W. Benson, Ltd., of Ludgate Hill, E.C , had written to the effect that Mr. Benson was opposed on principle to selling branded articles, and that they were not sold by his firm. The meeting concluded without agreement, but the tide was clearly turning.

Painted Names

Watches supplied to the British market before the late 1920s usually left the factory in Switzerland with blank enamel dials. Sometimes the retailer's name was painted on in 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. However, enamel paint is much less durable than the vitreous enamel of the dial itself and, in surviving examples, has usually more or less fallen off. One exception to this rule are watches with Mappin „Campaign” that was fired onto the dial when it was made. But note that Mappin was a British retailer, not a Swiss watchmaker.

The advert by Baume & Co. from the Horological Journal of 1911 reproduced here is evidence of this practice. Longines watches were very highly regarded by the watch and jewellery trade in Britain, and took numerous top places in observatory competitions. But the advert says that they are supplied “without any distinctive name or mark except that of the retailer”. This is not something that Baume or Longines wanted to do. If the Longines name were put prominently onto the watches, British retailers would simply refuse to order them. Baume and Longines were immensely proud of the quality of their watches, but they were also pragmatic; they needed to 'shift product' in order to make a sales and a profit. Given the intransigence of the British retailers, they made a virtue out of necessity and made it clear that they were willing, even if they were not happy about it, to supply watches without branding.

If you have a watch dated earlier than 1930 and it has a Swiss manufacturer's name or logo on the dial, you need to be aware that this might have been added later, even quite recently, by someone trying to give the value of the watch a boost. This deception is most often found with early Rolex Watch Company items, where "Rolex" is painted onto the dials of not only actual early Rolex watches, but also the dials of Rolex's other brands such as Marconi, Unicorn, and other watches that would never have been called Rolex watches by the Rolex Watch Co. I explain why Hans Wilsdorf created brands other than Rolex at Wilsdorf's Other Brands. Before I started to expose this practice, there were few lengths that the unscrupulous would not go to. I have even seen a Marvin wristwatch from 1915/16 with Rolex laser engraved in the case back and on the barrel bridge, and Rolex painted onto the dial. Needless to say, the watch had nothing to do with Rolex.

Evidence from Longines

The dial shown here is from a Longines wristwatch. This dial has been through an ultrasonic clean, which is interesting because the name words Mappin and „Campaign” have not been affected. This is because the words are vitreous enamel fired into the enamel of the dial, the same as the tracks and numerals, not painted on later with enamel paint as is usually the case with British retailer's names, and which don't survive a trip through the ultrasonic tank. This, together with the opening low quote mark „ which is not used in English, shows that the name was put on in Switzerland by the dial maker as the dial was being made. Longines told me that the requirement for this dial is recorded in their archives showing that the watch left the St Imier factory in 1916 with this branding on the dial – but note, not the name Longines or the Longines logo.

Longines watches supplied to other countries at the time often, or perhaps always, had Longines fired onto the dial. From about the mid-1920s this began to be accepted in Britain. The earliest British imported Longines wristwatch that I have with a genuine Longines logo on the dial has London Assay Office import hallmarks in the case for 1928 to 1929. The Longines name is semi-circular around the top of the sub-seconds track. This of course still left the space between the 12 and the central hand boss available for a retailers name.

Fired or Painted?

How can you tell whether the name or logo was fired into the enamel, and is therefore original, or has been painted on later? Enamel paint is quite different from vitreous enamel and nothing like as durable. It is a solvent based paint applied cold with a brush, just like any other paint. Enamel paint does not stick well to glass, which is essentially what a vitreous enamel dial is made of. Names painted onto enamel dials 100 years ago have mostly flaked off partially or even completely in the intervening years.

When a retailer's name was painted onto a dial in enamel paint, by now it has partly or almost completely worn away or flaked off over the years, whereas the rest of dial markings in fired vitreous enamel are still crisp and sharp. The image of a Borgel watch here shows exactly this. The watch is an IWC in a black oxisdised steel case that was imported by Stauffer & Co. in 1908 and supplied to Hamilton & Inches in Edinburgh who retailed it. The Hamilton & Inches name and Edinburgh can still just be made out, althuogh it helps if you already have an idea of what you are looking at, but the paint has dulled to matt and mostly flaked off the otherwise pristine enamel dial. This is an easy indication that the name was painted on after the watch was made.

When you have looked at a lot of original early twentieth century watches without a manufacturer's name or brand on the dial, seeing one immediately looks wrong and not original. However, these days people like to see a brand name so sometimes well known names are added to the dials of watches in an attempt to boost their value. A name painted on recently using enamel paint can be difficult to identify, but there are several ways in which such an addition can be identified.

• Look carefully across the dial at an oblique angle with a lens in good light. As the cross section shows, enamel paint stands up proud of the surface unlike the fired enamel numbers which are virtually flat. If you can see the name standing up like this it has definitely been added, but a very skilful painter will make the letters very flat so some painted names can be difficult to detect by this method.
• If the writing looks crisp and sharp, it is not original. Original paint has partly or almost completely worn away or flaked off over the years. It is possible that original writing has been renewed, but witout a record of what the dial looked like before this was done it is impossible to know what was there originally, if there was anything at all. If the writing makes the watch more valuable by adding the name of a famous maker that is not found anywhere else on the watch, then it is often fake.
• Wipe the suspect lettering with a solvent that dissolves paint such as acetone. Names fired into the enamel will not be affected by the solvent whereas names painted on later will dissolve and wash off, leaving the original enamel details of the dial intact.

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Dial Refinishing

Enamel dials require little in the way of refinishing compared to the printed and lacquered dials that followed. Think of the difference between cleaning a glass dish and a glossy magazine. The glass dish can be plunged into warm soapy water and will come out looking like new, but you can't treat a glossy magazine the same way. In fact, printed and lacquered dials can only be very lightly cleaned, and a badly degraded dial will have to be either left as it is, which is often the best option, or completely stripped of its original finish and reprinted, which never looks exactly the same as the original.

Non-luminous enamel dials and hands have no paint. The dial can be cleaned in many ways, but if it has cracks, an ultrasonic wash is a good method because it removes dirt from the cracks and makes them less visible. Hands are often heat blued steel, which can be polished and re-blued.

Removing paint from a luminous enamel dial and hands is relatively easy, but radioactive materials in the original paint mean that many companies will not take on this work. Putting paint back on the numerals and hands to match the original is important. Close up photos of the dial and hands should be sent to several companies with a detailed description of what you want, asking if they can do it in the way that you wish. If you want the dial and hands to look exactly like they do now, paint colour and finish included, make sure you say so. Be as detailed as you can in describing what you want, don't imagine that they will know.

Think carefully about getting radium paint on an early dial replaced with luminous paint. The old radium paint no longer glows in the dark, so if you replace it with luminous paint which does, it will be obvious what has been done. Replacing radioluminescent paint is a good thing, it eliminates the radiation and radon problem, making it obvious that the paint is a modern luminous compound and not the old, non glowing, radium based lume.

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Hand Styles

It seems obvious to say, but the style of the hands should match the style of the dial, and the hands should match each other.

Old watches have sometimes had their hands replaced, which might not be obvious when you first see a watch that you are interested in, but becomes more painful to look at as time goes by, and can be difficult to rectify. The reason that the wrong hands were fitted by a watch repairer in the past was that hands of the correct style, in the correct lengths and with the correct size holes to fit the hour and minute pinions, were not available at the time, and can be equally if not more difficult to find today.

Hands should also be the right length. The minute and seconds hands should terminate on their respective tracks, and the hour hand should point to or just touch the number.

Luminous Hands

If the numerals on the dial are skeletonised for luminous paint, the hands should also be skeletonised to take the same luminous paint. There would not be much point in being able to see luminised numerals in the dark if you couldn't see where the hands were!

The correct shape for the hands of a trench watch is shown in the image here. The shape of these hands was called in Swiss/French “poire squelette” (the second word is pronounced “skelette”) that is “pear skeleton”, presumably after the pear shaped bulge at the end of the hour hand.

This style is referred to in manufacturers catalogues of the time as “Luminous” or often simply “Radium”. The hands are sometimes referred to as “cathedral” hands because they look a bit like a stained glass leaded window.

Luminous hands like this became widely used during World War One as an essential feature of a trench watch. The luminous effect was created by radioluminescent paint that used radium and other radioactive elements to power the glow, hence the name Radium for the style of hands.

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The Date Window

Who invented the date window, the little window on a wristwatch dial that shows today's date?

I am pretty sure that Rolex would like us to think that it was them. Today the Rolex web site (accessed 15 August 2019) says “The year 1945 saw the birth of the Datejust, the first self‑winding wrist chronometer to indicate the date in a window on the dial.” This is not quite the same as saying that Rolex invented the date window in 1945, but without the qualification “self‑winding wrist chronometer”, which I am sure that many people would see as just a fancy way of saying wristwatch, it would say that the Datejust was the first watch with a date window.

Rolex did invent the “cyclops”, the magnifier in the crystal that magnifies the date to make it easier to read. This is said to have been inspired by Betty, Wilsdorf's second wife, who complained that the date on her ladies' Rolex wristwatch was too small to read. The cyclops was introduced in the early 1950s.

However, Rolex did not invent the date window itself.

Jean-Louis Jeanmaire

The earliest patent yet seen for a date window is illustrated by the figure from a Swiss patent reproduced here.

It is Swiss patent No. 5139, dated 19 June 1892. The patent was granted to Jean-Louis Jeanmaire, of Orvin near to Bienne. It is titled Quantième à guichet pour montres et pendules or Calendar window for watches and clocks.

The diagrams in the figure illustrate the method of operation.

The date is displayed through a hole in the dial by two circular discs, one numbered 0 to 3 and the other 0 to 9 to allow the full range of dates from 01 to 31 to be displayed. The day of the week is displayed by a third disc through a second hole in the dial below the centre.

The day of the week and the 0 to 9 disc are moved forward by the watch mechanism every twenty four hours. As the 0 to 9 disc completes its revolution, which takes place every 10 days, the index labelled d between the 0 and 9 on its periphery moves to 0 to 3 disc on one place.

The indexing of the date discs would allow 32, 33 etc to appear after 31, but the patent mentions that there are three pushers that enable the discs to be moved at will to any desired position, so presumably the owner of the watch was expected to change the date from 32 to 01.

The separation of the first and second digits of the date onto separate rings is reminiscent of the big date display introduced by A. Lange & Söhne at its relaunch in the Lange 1. Indeed, the patent granted to Jeanmaire says that the two disc construction allows it to be applied to ‘un quantième de très grandes dimensions’, a date of very large dimensions. Lange are careful to say that theirs is the first example of a big date display being used in a wristwatch.

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Marlys' Date Watch

The advertisement from the Watchmaker & Jeweller, Silversmith & Optician for October 1930 clearly shows a wristwatch with a date window; a “Marlys Date Watch” in fact.

In small print the advert says “Patents applied for in all principal countries.”

The fact that the Marly's advertisement says "Now - Marlys gives the date ..." suggests that they thought this was the first wristwatch with a date window. They were granted Swiss and French patents, but although an application was made for a British patent, it was never granted.

• Fabrique d'Horlogerie Marlys S. A. of La Chaux-de-Fonds was granted on 15 December 1931 a Swiss patent for “Mécanisme indiquant le quantième du mois pour montres et pendulettes” or mechanism indicating the date of the month for watches and clocks, the priority date being 16 July 1930.

• The same device was granted a French patent under the title “Mouvement d'horlogerie à quantième”

• An application for a British patent under the title “Date indicating mechanism for watches and small pendulum clocks” was also lodged, but this was allowed to become void.

Marlys seem to have been particularly interested in dials. A patent was granted to them in 1928 for “Instrument permettant de reconnaître si un tour d'heure est correctement placé sur son cadran” or an instrument to recognize if a time lapse is correctly placed on the dial. This was a device for checking that dials were laid out and divided correctly. The purpose was for dial makers to be able to see if a dial printing machine was working properly, or by watch manufacturers to check that dials sent to them were free from defects.

Marlys appear to have been an assembler of watches. Movements of Marlys watches are marked “FEF” for Fabrique d'Ébauches de Fleurier.

The British agency for Marly's was taken by Adie Brothers who then traded under the style “Adie-Marlys Watch Company” at Craven House, 121 Kingsway, London.

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Graef & Co Kalenderuhr

Jon Hallet discovered an application for a British patent with a very similar mechanism, "A watch or clock with a device for indicating the day of the month". This mechanism, called a “Kalenderuhr” was invented by the Swiss company Graef & Co of La Chaux-de-Fonds. The application priority date was 31 January 1930 and it was granted Swiss patent No 148818 on 15 August 1931.

The British rights to this patent were assigned to Claude Lyons of the Vertex Watch Company who made an application for a British patent. This was given the provisional number 377,953, but no patent was granted and the application, like the Marlys application for a British patent, became void. However, the priority date is nearly six months earlier than the Marlys' patents, so at the moment this Kalenderuhr date window is the earliest known.

Unlike the Marlys design, which has the date window below the 12, the Graef & Co Kalenderuhr design placed the date window at the now-familiar position of 3 o'clock on the dial.

Patek Philippe

In the Patek Philippe museum there is a perpetual calendar pocket watch with the date in an aperture at 10 o'clock, and also the day of the week and the month shown through other apertures in the dial.

This watch dates 1928-1929, just a little bit before the Graef & Co Kalenderuhr patent.