André Hessen (1745 – 1805) was born in Sweden, settled in Paris in 1767, where he worked as experienced watchmaker. In 1775 he became watchmaker to ‘S.A.R Monsieur’, meaning to ‘Son Altesse Royale Monsieur’ which translates to ‘His Royal Highness Mister’ and refers to the brother of Louis XVI, King of France: Charles Philippe Comte d’Artois. Hessen was a close collaborator of Lépine and although highly convinced of the importance of the verge system, he later made watches with experimental escapements as well as watches with highly decorated enamelled cases. 1785 he published in London and Paris his thoughts about a new method for constructing watches (a discussion about the Lépine caliber). As mentioned above, he was a critic of new types of escapement, as Berthoud, used exclusively the verge escapement well passed 1780, still he must have recognised the advantages of this new types of escapements and later used the virgule escapement a lot. In 1790 Hessen returned to Stockholm.
The Lépine – Hessen movement, 1780 – 1790
The development of the bridged calibre by Lépine coincided with the new fashion of larger and thinner watches slowly spreading over the channel from England in about 1775. In England, larger watches were already in fashion since the publication of George Harrison’s H4. A large watch (ideally with central seconds) represented the new fashion statement and made owners appear to be connected with the important new scientific discoveries in astronomy and geography. The movements equipped with verge escapements, which were still largely used for their toughness, could hardly compete with these new technical and aesthetic developments.
Still, André Hessen defended the advantages of the verge escapement, being used for over 200 years, being robust and easy to service and declared the new escapements, mostly adapted from England, as ‘fashion statement’ without technical merit. His solution to stay competitive, was to adapt the verge movement aesthetically and to some regard also functionally to Lépine’s new and revolutionary advances, with the main feature of keeping the whole wheel work hidden and protected and not exposed like Lépine did in his last versions.
Lépine – Hessen movement – Type I, 1780
The method Hessen found for his first caliber version, developed towards 1780, was to enclose the wheel train, as Lépine did in his first transitional caliber, having fusee and main barrel showing through the main plate and reducing the back plate to a crescent shaped ‘bridge’ which holds the fusee and main barrel. On the dial side an additional bridge is added to hold the escape -and 3rd wheels. All these changes guarantee for a very slim construction and an easier maintenance of the movement, because single components can be removed without disassembling the whole piece. This Hessen-verge-caliber was thought to be a serious competitor of the Lépine movement.
So it’s not surprising that a few Paris watchmakers and watch retailers, Abraham – Louis Breguet among them, used this updated version of verge movement. Hessen must have tried to promote them, by offering them for a cheaper price as the Lépine movements. Still, these early Hessen-verge-calibers were rarely used and very rarely survive.
New evidence shows that until 1783 the workshops of Lépine (Rue des Fossés St. Germain l’Auxerrois, now Rue de la Monnaie) and André Hessen’s workshop (Rue Mercier, now part of the Rue de Viarmes) were only a few 100m apart. Moreover also Breguet’s workshop (Quai de l’Horloge) was within walking distance (under 700m) to both other workshops at that time, which explains the use of identical calibers in all three workshops and confirms that the three watchmakers must have known each other.
Lépine – Hessen movement – Type II, 1784
The second version of Hessen’ caliber, introduced towards 1780, does not use verge escapements any longer and he’s aligning with Lépine in dropping the fusée completely, while keeping the wheel work enclosed.
By then Hessen finally recognised the advantages of the new escapements, he modified his enclosed movement to receive the virgule escapement. He also dropped the two-footed cock of his first version for the more elegant one footed Lépine-style cock, while retaining the Louis XVI-style decoration on it. Latter virgule escapement version of the Hessen-movement was more largely used. On the long run even the updated Hessen-virgule-caliber could not compete with the even slimmer, more practical and more precise, bridged movements by Lépine.
Lépine – Hessen movement – Type III, 1786
One third version of the Hessen movement is a partial ‘reconciliation’ with the Lépine system by retaining the virgule escapement, modernising the decoration on the cock, making it completely in style of Lépine and some of these versions have a hanging barrel, as Lépine designed them, still keeping the wheel work completely enclosed. These last versions described as Lépine-Hessen-movements were used between 1786 and 1790.
Also Breguet, among other Parisian watchmakers used this caliber, as can be seen in No. 135, sold in 1792. Please note, that latter watch is clearly not made in the Breguet workshops and is a ‘retail piece’, most probably bought directly from Hessen, as can be deduced from the lacking signature on the original dial. Moreover the whole design of the case with the application of pearls and translucent enamelling on the guilloched metal surface, does not correspond to the usual design of the Breguet output of that time. The sale of this watch is mentioned in the ledgers, otherwise one could think of a contemporary forgery.
Finally after 20 years criticising Lepine for pseudo-revolutionising horology, as Hessen insinuated in a pamphlet of 1767, he had to admit, that Lepine’s method was better.
Antiquarian Horology 
