Jean Antoine LépineCopyright © David Boettcher 2006 - 2020 all rights reserved.
The Lépine Calibre
Around 1764 Jean-Antoine Lépine (1720 - 1814) of Paris designed a new layout for the pocket watch that was much thinner than had been made previously, so that it could slip easily into the pocket of a close-tailored waistcoat. The waistcoat had been introduced into English fashion by King Charles II in 1666, derived from a Persian vest worn by Sir Robert Shirley, an Englishman who had lived in Persia and became Persia's ambassador to the court of Charles II. It was initially a loose fitting garment that extended down to mid-thigh. The waistcoat was subsequently adopted in France and by 1770 in Paris the fashionable fit of the waistcoat had become shorter and tighter, much like the waistcoat worn today as part of a three piece suit. This of course required a thinner watch to avoid an unseemly bulge.
Watches at this time normally had the train wheels, the fusee and the verge escapement mounted between two plates, with the balance mounted on the outside of the top plate. This made them thick to start with, and then they often had an outer case or a hunter lid over the crystal, which made them bulky.
The traditional vertical verge escapement dictated that the balance occupy its traditional position on the outside or top of the top plate. To make a thinner and flatter watch that would fit comfortably in a waistcoat pocket, Lépine used horizontal escapements such as the cylinder or virgule instead of the upright verge, which allowed him to move the balance from above the top plate to between the plates, so that it was in the same plane as the train wheels. The cock for the balance staff top pivot was fixed to the bottom plate instead of to the top plate, with the bottom pivot of the balance staff in the bottom plate.
Lépine realized that using either the virgule or cylinder escapements, which are ‘frictional rest’ escapements, meant that the bulky fusee could be dispensed with, and the mainspring barrel was pivoted in the bottom plate only, in a cantilever arrangement with no top bearing. The barrel is the item that normally determines how far apart the plates have to be, because it has to house a spring which must not be too thick and therefore must be of a certain width.
From Lépine's creative mind flowed other improvements which became standard practice in later years, such as winding and hand setting from the from the back of the movement, barrel stop work and wolf teeth profile gears for the winding wheels.
With a single top plate, there is a limit to how close it can be to the bottom plate because the watchmaker needs access to guide the pivots into their holes. To make the movement as thin as possible but still possible to assemble, Lépine replaced the single piece top plate with individual cocks or bridges for the top pivots of the balance and train wheels so that they could be fitted one by one. For the spring barrel he even dispensed with the top pivot, cantilevering the barrel off the bottom plate only. This design was called at the time the Lépine calibre.
Lépine and Breguet
Lépine was working before Abraham-Louis Breguet (1747–1823). The exact nature of their relationship, if any, is unknown. It is known that they had a business relationship over many years since the Breguet archives record many watches that were supplied to Breguet by Lépine.
In later watches, Lépine used a lever escapement very similar to that used by Breguet, exactly the same kind of temperature compensation and also the parachute shock protection device for the balance pivots. Breguet also used ‘wolf teeth’, invented by Lepine, in the winding train of his perpetuelles. The style of hands called Breguet hands were used in Lépine watches before Breguet began work as a watchmaker.
Adolphe Chapiro and others are of the opinion that at some stage Breguet was taught by or worked under Lépine. Whether Breguet was an apprentice of Lépine is unproven, but it is possible that Lépine should be given credit for many improvements that are generally attributed to Breguet.
Lépine and Voltaire
From 1759 to 1778 the small village of Ferney, on the French side of the Swiss border near to Geneva, was home to French writer and philosopher Voltaire, who moved there to escape from the strictures of the Calvinist regime in Geneva. Voltaire encouraged Geneva craftsmen, including watchmakers, to follow to Ferney him so that they could practice their trades without retrictions. After the French Revolution, the village was renamed "Ferney-Voltaire".
Lépine was involved in Voltaire's watchmaking activities in some way as yet not fully known, but it appears that most of the ébauches for Lépine's watches were made there in the years between 1778 and 1782.
Lépine and Savonnette Styles
All watches today have the balance mounted on the bottom plate and use horizontal escapements, so why do we call some of them Lépine and other savonnette? Well there is a clue in the name savonnette, which is the French for a small round cake of soap with slightly domed top and bottom. A watch with a hunter lid resembles this when the lid is closed, and from this it is evident that the name savonnette means a hunter style watch.
To make his watches even thinner, sensationally thin in fact, Lépine didn't use a hunter lid, so the crystal was exposed and Lépine watches were ‘open face’. This new design caught the fashionable mood of the time and the demand in Paris was for one of Monsieur Lépine's watches. Of course the general public didn't understand or care about the details of Lépine's changes to the construction of the movement, they just wanted one of the newly fashionable watches, the most distinctive characteristic of which was the open face, so in time any open face watch became called Lépine.
Because an open face watch has no outer cover, rather than holding the watch in one hand and using the other hand to open the cover, it is more natural to view it with the pendant held vertically, so Lépine rearranged the layout of the dial to put the pendant at 12 o'clock. The meant that the small seconds display on the dial, when it was used, had to be moved so that it was opposite the pendant rather than at right angles to it. To achieve this the layout of the gear train was laid so that the arbor of the fourth wheel (which carries the seconds hand) was placed on a line projected from the axis of the winding stem. Most if not all of the watches made by Lépine didn't have small seconds, so it is unlikely that this movement layout is named after him, rather it is called Lépine after the open faced Lépine watches in which it was used.
An early Stauffer Lépine calibre
Adolphe Chapiro categorised stages in the development of Lépine style calibres from I to V as follows:
- Original Lépine calibre with round bridges 1795-1800
It must not be assumed that the introduction of a new style caused the previous styles to be discontinued. In fact, earlier styles continued alongside the later styles for many years, and in some cases for many decades. The new styles introduced technical improvements but required old tooling to be replaced, so in many cases the old styles continued to be produced as they were cheaper to make. Customers were not always demanding improvements, but were always wanting the best price.
Here is the movement of a pocket watch produced in the Stauffer Son & Co. Chaux-de-Fonds factory some time between 1830 and about 1850. Adolphe Chapiro describes this layout as ‘Lépine-Calibre IV’, with a bridge for the centre wheel instead of a cock, and says that this layout was used from 1835-1850, after 1850 a layout with the barrel bridge a straight bar and the cocks arranged more in parallel was used. However, I have seen a watch with an identical layout in a Swiss case with English hallmarks for 1880 to 1881, so production of this style of movement carried on after 1850, although not by Stauffer who by then had moved on to making lever escapement movements.
The terms "Lépine movement" or "Lépine calibre" are not a brand name or maker. Used in the broadest sense they describe either an open face watch or the type of movement invented by Lépine. These were called "bar movements" by the English because they had the top "plate" made up of "bars" — cocks and bridges — rather than a full, three quarter or half plate. This style of movement was made by many watch makers in France and Switzerland during the 19th century.
So, the term Lépine can be used to refer to any one of the following:
- An open face watch.
- A style of movement with the top "plate" made up of "bars" — cocks and bridges.
- A movement with the fourth wheel on a line projected from the axis of the winding stem.
Copyright © David Boettcher 2006 - 2020 all rights reserved. This page updated September 2019. W3CMVS.