A brief description of technical terms used in describing clocks and watches

Acier Garrantt Sometimes you see the mark 'ACIER GARRANTT' on the back of a watch. The mark simply states (in French) that the case is Guaranteed Stainless (steel)!

Adamantine According to a reply in a NAWCC bulletin, Adamantine is a veneer made from celluloid made up of cellulose (cotton), nitric acid and Camphor. The paper thin veneer is highly flammable and is very vulnerable to heat, including sunlight. The material is very tough. To clean it, Seth Thomas originally suggested just using rag with 'sweet oil' on it (Sweet oil is a vegetable oil similar to Olive Oil). Do not use ANY acids or abrasive polishes on this material.

Ancre Ligne Droite The watch has a ‘straight-line lever’ escapement

Brevet or Brevet SGDG These names are often found on French or Swiss clocks. It is not the name of the maker. The word Brevet is similar to the English 'Patent'. If it appears on a clock or watch, it simply means that patents that have been previously registered have been incorporated into that item.

Compensateur This refers to the fact that the balance wheel is temperature compensated
Echappement en Ancre This means that it is equipped with a lever escapement

DRGM or Deutsches Reichs, Gebrauchzmuster type was a utility model patent (not to be confused with the Geschmacksmuster - the registered or industrial design type). These "small" or "petty" DRGMs were available from 1891 until 1945. For more details of when different DRGM numbers were issued - click here

DRP The DRP, or Deutsches Reichspatent, was a "proper" patent - assigned from 1877 until 1945 in Germany. For more details of when different DRP numbers were issued - see click here

Galonne The word Galonne means 'mechanically gold plated silver' . This can often be confusing as the plating might have worn off and you are left with just the plain Silver watch.

Incabloc This is a type of shock protection on watches. for a more detailed description see Incabloc

Jewels Jewels are inserted in, mainly watches, to reduce friction on the gear train. Until the 20th century, watch jewels were made of ruby, sapphire, aquamarine, garnet, and diamond. I have seen colourless jewels which might be quartz, or low grade (colourless) aquamarine. Pale blue ones are aquamarine or low grade sapphire, and pink ones can be low grade ruby, or possibly garnet. Sapphire and ruby used was usually not of jewellery grade. Diamonds saw limited use, but they show up as balance wheel cap jewels periodically.

Kahmen Kahmen is russian for jewels. Therfore the Kahmen 15 shown below means that it is a 15 jewel watch.

Karussel This name strictly refers to a particular type patented by Bonniksen of Coventry (U.K.) in 1894 in which the platform revolved once every 52.5 minutes; it was a refinement of an earlier device called a ‘tourbillon’ in which the period of rotation was usually much shorter. Perhaps, as this watch was made so soon after the patent date, it is actually Bonniksen's work

Marque Deposee Marque Deposee simply means "Trademark".

Parachute This refers to the method of fastening the balance wheel cap jewels
Reveil This means "wakening" or alarm in French. It is used on the dial of some alarm clocks to indicate that an alarm is featured.
Schutz Marke The mark simply means (in German) 'Trade Mark'

Spiral Breguet The hairspring is of the ‘Breguet’ or ‘overcoil’ type, with its outer end bent inwards and fixed over the inner coils; this arrangement, named after its inventor, helped to ensure that the spring always vibrated at the same speed whether the watch was fully wound or almost run down.

Known Trade Directory listings from trade directories that we have currently catalogued

None Found.

Note: Due to the dynamic nature of the addition of Trade Directories to our library, these results may show additional dates to the text above.

Known Published Photos or articles

Please note that due to British copyright laws, we are not able to show any photos or articles mentioned below. However, the books etc should be available for order from your local library or see Links page for details of places to obtain copies of the sources listed below)


Sources (see Links page for details of places to obtain copies of the sources listed below)



The above information and dates are correct to the best of our knowledge based on the current books etc in our library at the time this page was last written or amended. Please be aware that any dates given are not necessarily the start and finish dates of this maker, they are just the dates that it is likely that he was working based on the information we have found. These are taken from trade directories etc and it is quite possible that they were working for longer periods than shown above.

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This web site, was run by Rosemary Harrison-Smith with the help of Tony Harrison-Smith FBHI, was started in 1997 and it held information that we have found about various clock and watchmakers, and has 35,758 records in its database. The information comes from listings published in books and trade directories that we had in our library, giving dates that makers are known to have been working. The database includes 31,947 individual trade directory entries from 363 trade directories and more detailed biographies for 4276 makers and retailers.

The information is not necessarily all there is to know about the maker, but it is a digest of all we have found in our researches. 
We specialise in British and Irish makers.
The site is now archived so that researchers can view the information held in the database for a daily charge.