The present lot is one of the first calendar watches designed and produced as a wristwatch, as opposed to being converted from a pocket watch.
A similar watch, No. 256899, is illustrated on the cover of Wristwatches - History of a Century's Development by Kahlert, Mühe & Brunner. It is further illustrated and discussed on page 314.
Johann Heinrich Moser, better known as Henry Moser, was born on 12 December 1805 in Schaffhausen, Switzerland. His father Erhard Moser (1760-1829), was a clockmaker and city councilor.
In the early 20th century, Moser as well as other Swiss watchmakers such as Paul Buhré and Tissot, were the main suppliers to the Russian market, notably to the Imperial Court and Carl Fabergé.