Collector's Pocket Watches, Wristwatc...

Noga Hilton, Geneva, Apr 12, 2003

LOT 301

F(riedrich) Hauth, Horloger de la Marine Imperiale, St. Petersburg, No. 43, circa 1850.Important and very fine eight-day going, double barrel marine chronometer with constant-force detent escapement and regulator dial in a wooden fitted box.

CHF 25,000 - 30,000

EUR 17,000 - 21,000 / USD 19,000 - 22,000

C.Three-piece, brass, plain in mahogany two-part fitted box. D. Silvered, radial Roman hours to the left, symmetrically seconds, center Arabic minute track. Blued steel "spade" hands. M. 77 mm., brass, full plate, jeweled escapement with diamond endstone on the balance, constant-force chronometer escapement, bimetallic Pennington type cut compensation balance with six temperature screws and four mean nuts, blued steel helical balance spring with terminal curves.Signed on dial and movement.Diam. 80 mm., box: 115 x 130 x 64 mm.


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Grading System
Grade: AAA

Excellent
Case: 3
Movement: 3*
Dial: 3-21-01

Period

HANDS Original

Notes

The instrument incorporates an unusual constant-force escapement invented by Hauth as he proudly inscribed on the dial. The impulse is given by a spring-loaded (helical hairspring) pivoted lever, which, at a certain moment of the impulse, releases one of the two concentric escape wheel locking detents. The Earnshaw type detent is released by an unlocking jewel mounted on a roller of the balance staff. Each locking lever acts on its own escape wheel. Both escape wheels are concentrically mountedon the same arbor. The unlocking releases the double escape wheel which, via an additional lever on the impulse detent, winds it, making it ready for the next impulse. The invention Hauth refers to lies in the synchronization of the unlocking levers, hence the double escape wheel. Each wheel has 15 teeth. Both can be easily adjusted in respect to each other, thus controlling the length of the impulse. Hauth set them off half a tooth (12o), which gives a nice amplitude.Friedrich HauthWas a very talented chronometer and watch maker who received many awards. His business was on Nevskii Prospect in St. Petersburg, where he was listed between 1828 and 1849. Between 1836 and 1837 he made an astronomical clock for the St. Petersburg University, and as soon as he finished it he began working on one for the Pulkova Observatory. Between 1845 and 1849 Hauth was chosen to service the chronometers of the St. Petersburg Academy of Sciences. In 1843 he contributed nine chronometers for thpurpose of finding the difference in longitude between Altona (Hamburg) and Pulkova Observatories. Two of them are recorded at the Royal Observatory at Greenwich in 1854.