Monday, 15 January 2018

Watchmakers Service Marks.

I am sometimes asked what the meaning is of the small scratched numbers and letters  often found scratched onto the inside of the back or dust cover of a watch. They are service marks put there by watchmakers.

In America the prefix will usually tell you who last serviced or sold the watch, IIRC a practice originally a legal requirement to try and prevent (tax?) fraud but now done on a voluntary basis and organised by the American Watchmakers – Clockmakers Institute.

In UK we are not so lucky and the marks are normally just a ledger or job number and some codes only meaningful to the watch repairer who made them. Just occasionally however you come across something different.
Inside the back of this watch by Review, signed by Jewellers Sharman D Neil Ltd of Belfast and in a Swiss silver case assayed in London in 1926 there are 4 “normal” marks that mean little, except perhaps that one has a prefix NL which could be a contraction of Neill.
But there is also a block of marks all by the same repairer, shown at the top of the page. Easy to read with a loupe but very difficult  to photograph, after some serious work with Photoshop we can see that each has a (ledger?) number, followed by “M” and then what must be the month and year and what are probably initials of the workman.

 Someone clearly looked after the watch as it was serviced in October 1935, then in 1938, 39, 42, 44, 47, 49 and then in April 1953.

Wednesday, 8 November 2017

A Pocket Watch for use on Nuclear Submarines.

I was a little sceptical about this but the story checks out. The watch is a standard size 16 Waltham 1908-1609 with 9 jewels, a Swiss lever escapement and a Breguet sprung cut compensated balance with double roller. It is adjusted for temperature and in three positions. The serial number dates it to 1942.

As confirmed by the catalogue number it was originally supplied to the Royal Navy during WWII with luminous hands and face, it was retained at the end of the war, unlike around two million pounds worth of surplus watches and clocks that were sold off.

Later, following the introduction of Nuclear submarines in 1960, it was given non-luminous hands and dial so that the relatively high radiation levels (by todays standards) would not confuse on-board radiation detection equipment. The case was then stamped "Non-Lum".
The American screw backed case is in base metal case and was made by the Star Watch Case Company, it is stamped with the military catalogue number, the Military property mark, the service allocated serial number and "Non-Lum" as described above.

Monday, 4 September 2017

The last version of the Bank watch by J.W. Benson.

The "Bank" Watch was in production a long time, by 1935 a new version was introduced that was almost certainly the last, it is rare and the one pictured is the only one that I have seen.

Although in general layout it is similar to the previous ones this version was much slimmer and had the dial secured with screws rather than pins but amazingly they stick with the slow train movement that most makers had replaced with the fast train 40 years earlier.

I don’t know if it was made in house or bought in but I suspect it was either the former or they used outworkers making to their specification.

One interesting point is that historically the “Bank” watch was cheaper than the Ludgate but this version of the “Bank” was more expensive as explained in this section of a contemporary Benson sales catalogue.

Sunday, 28 May 2017

Dating a Russell Fusee Hunter

11J Hunter signed Thos Russell & Son. Liverpool
There was something odd about this watch when I saw it listed for auction, the case was clearly hallmarked at Chester in 1914 but the movement looked older than that. It is also very unusual to find a "Consular" type case as late as 1914, in fact I don't recall seeing one that late.

When it arrived my suspicions were confirmed as the movement has a very "slow train" running at 15,400 Vibrations Per Hour which was obsolete by the early 1890s. Further research also showed that the trading name on the dial was in use from 1859 though 1894 and the address probably from after the late 1870s.

Case hallmarked in Chester 1914, maker's mark S.Y for Samuel Yeomans.

The case however clearly belonged to the movement they have the same serial number. So the movement had must have had a new case made for it in 1914, a telling point for the provenance of the movement was the makers mark on the case of S.Y, this is for Samuel Yeomans who was mention in my last post but one on a Harrison watch, where there is some background on this important figure in Coventry watchmaking.

The point is that Yeomans was in the business of manufacturing watches, he was not a case maker and it is very unlikely that someone would go to the company for a new case, and the company was unlikely to provide one, unless they had originally made the watch.

So whilst Russell was, I believe, still making watches when this movement was made he is also known to have been buying in watches from Coventry and this is one of them, almost certainly made by Yeomans from a Prescott ebauché (the ebauché makers mark "M.M" is stamped on the movement).

The 11 Jewel Fusee Movement c 1880

This all helps with dating, at first sight from the design etc. the movement is likely to be from c 1850 through to c 1900, the use of a 15,400 VPH slow train narrows this further to a latest date of c1890. The use of a Prescott ebauché probably confirms 1890 as the latest date as by this time Yeomans was also chairman of the Coventry Watch Movement Company who were making Fusee ebauché [3] for the Coventry trade and he was hardly likely to buy in a Prescott ebauché [1]

In 1877 Yeomans [2] was working with Newsome and their movements were marked  "N&Y" as was the Harrison from that date.

So the movement is between c1878 and c 1890 and in my view given the obsolescent very "slow train" most likely from c 1880.

[1] The CWMC did on occasion by in ebauché from The Lancashire Watch Co of Prescott but this is not one of them.
[2] Yeomans first registered is silver mark in 1874, probably for watches made with Newsome - the two together did not have a mark that I can find. It is therefore unlikely that the movement is earlier than 1877.
[3] The CWMC started off making Fusee ebauché  but quickly realised their error and re-tooled for going barrel movements.

Fusee Maintaining Power

One drawback of a Fusee is that power to the movement is lost whilst the watch is being wound, very often this was accepted on Verge Fusee watches but most Lever Fusee watches were equipped with "Maintaining Power" to overcome the problem.

The components fitted to the Fusee cone to provide "Maintaining Power"

To provide maintaining power the Fusee has some additional components, on the right of the picture above we see the underside of the Fusee cone which now does not have the teeth on its edge to engage with the centre wheel pinion.

Instead there are teeth to engage with the two sprung loaded paws on the piece shown in the centre which fits beneath it.

The teeth on the edge of this piece engage with a paw on the movement to prevent it turning the wrong way. The paw is shown in the picture to the right bottom centre, it is swung away from the Fusee in the picture as its spring would push it over without the top plate in position.

The piece on the left has the teeth to engage with the centre wheel and a flat circular spring running in this picture from 3 o'clock around to 12.

The top of the spring has freedom to move about 2 teeth along the rim of the disk, a stud just visible (click on the image for a larger view) engages with the small hole at 12 o'clock on the centre piece, it will be under tension and will provide power to the train during the brief period power comes off with each turn of the key.

The assembly is kept together with a collar pinned to the arbour as shown in the final picture. The slot near the top of the disk is the business end of the maintaining spring. The rivet to the left is securing the other end of the spring.

Tuesday, 23 May 2017

One Watch - Four Names

Fusee Lever signed Harrisson & Son, Darlington. 1877.
The watch has a substantial size 18 Fusee movement in a silver case made in 1877. A nice, well made watch as well it might with 4 well known names associated with it.


Long Case Clock by W. Harrison of
Hexham c1825 and insert English
Watch Co Chronograph 1882 signed by
W.E. Harrison of Stockton-On-Tees.
The first and most obvious is that of Harrison (and Son) of Darlington on the dial and movement, the Harrison’s were a large clan of watchmakers from the north east of England, probably related to the John Harrison who won the longitude prise for his 18th century chronometers who originated in Northumberland.
Unfortunately without a great deal of research the actual relationships between the various branches of the family is likely to remain unclear, particularly as many of them were called John or William and several seemed to move around quite frequently.

As best as I can make out from Loomes[i], the Harrison who made our long case clock in the 1820’s and who was at the time based in Hexham (before that he worked in Newcastle upon Tyne and after in Morpeth, then Warkworth and then back to Newcastle) was probably the father or the uncle of the Harrison of Harrison & Son of Darlington.

The second and third names are a bit harder to find, but under the dial the movement is stamped “N & Y”, this is for Isaac J.T. Newsome and (Frederick) Samuel Yeomans, two important men in the Coventry watch trade in the late 19th century.

A Newsome finished CWCCo movement 1894.
Some years after the Fusee watch was made they were trading on their own accounts running two of the larger watch manufacturing operations in Coventry – although small by comparison by Rotherham – making high quality watches.
Unusually both signed at least some of their movements under the dial so they can be identified and they also had their own silver marks so many complete watches are also identifiable.

Early watches were from Prescott ebauché but both were early customers of the Coventry Watch Movement Company and for at least one it is easy to see why......

An unusual watch - made by the Lancashire Watch
Company but resold by Yeomans. 1896.
I have seen considerably more movements by Newsome which suggests that he had the larger business which may be attributable to Yeomans in 1889 being one of the founders and chairman of the Coventry Watch Movement Company. 

Later an S.T. Newsome[ii] was also involved with the CWMCo but it is unclear from my reading in what capacity although he was clearly senior as in 1903 he stood in for the then chairman at the AGM.
The forth big name is the case maker, John Hammon of Clerkenwell.

The Hammons were important makers with addresses in London from 1822 onwards (including a “Manufactory” in Sekforde St) and with what was probably another branch of the family in Coventry from 1869[iii].

[i] Watchmakers and clockmakers of the World, Brian Loomes, NAG Press, 2006.
[ii] Watches 1850 – 1980, M. Cutmore, David & Charles, 1989.
[iii] Watch Case Makers of England, Philip T. Priestly, NAWCC, 1994.

Sunday, 14 May 2017

Verge Fusees and Modern Mainsprings don’t mix.

A Verge Fusee signed by Thos Gilbert of Hythe, 1833.
As explained in some detail my posting “The Fusee Watch” a major problem to overcome in the design and manufacture of clocks and watches powered by a spring is the variation in timekeeping as the spring winds down and power decreases (a lack of Isochronism[1]), typically with high power it will run fast and then slow and perhaps running fast again when the spring is nearly exhausted as a lever movement develops a shallow but fast action.

It is a particular problem with escapements with high friction such as the Verge Escapement invented in the 13th Century and still being used in pocket watches well into the 19th century.
The problem was recognised and addressed by various means over the years, the first successful approach was the Fusee, described in detail my previous post, which provided variable gearing between the spring barrel and the train.
Various other measures contributed to improvements but one of the most significant developments in the late 19th and 20th centuries was the improvements in metallurgy (including a move from steel to alloy construction), design and manufacture of mainsprings which by giving them variable thickness along the length of the spring and other features, allowed them to provide a relatively steady “pull” from shortly after fully wound for at least 24 hours.

Now for the conservator we have a problem. The Fusee compensates for variable power from the mainspring but 20th and 21st century mainsprings are designed for “Going barrel” watches[2] to give reasonably constant power so when the mainspring is replaced the Fusee is over compensating.

The result is that Fusee watches will typically keep time with varying accuracy over time, most particularly those with Verge escapements.

The Verge Fusee:

This is the first proper timekeeping check (a few runs of 1 - 2 hours first got it to this state) on a jewelled Verge Fusee movement by Vale & Rotherham from 1828 with a new mainspring.
To mitigate the problem I will, when practical, shorten a much longer spring than would fit in the barrel, by removing the first third or so of the spring the rest will usually be more like an old spring but the best that can realistically be done is to set the regulation so that the watch keep acceptable time for 12 - 18 hours, in the example above setting it to start off running a little fast would see it keep time  within about 90 seconds throughout a working day. So don’t expect too much from a Verge Fusee watch.

The Fusee Lever:

On the left a Fusee from a lever movement, note that the grove for the chain
moves in at a steady rate. On the right is the Fusee from a Verge watches. the
grove at the edge of the fuse is moving in at about double the rate of the other
 and the difference between the gearing effect at full and low wind is greater
for Verge , particularly when it is remembered that the run time of the lever
would usually be somewhat longer.
The same problem applies to Fusee lever movements but because of other improvements, the low friction lever escapement and some improvements in mainsprings by the mid to late 19th century the Fusee was far less aggressive and a modern mainspring will therefor have significantly less impact on the lever watch than on the Fusee.

[1] Isochronism : The ability of an escapement to run at an even rate irrespective of the power supplied to it.
[2] In a going barrel movement the barrel containing the mainspring meshes directly to the centre wheel (or sometimes in English movements, notably by the Lancashire Watch Co, through a dummy Fusee – just an extra gear in the train - to give anticlockwise winding) rather than via a Fusee.