The Historical and Memorial Museum of the Demidovs presents an astrolabe — a device for determining horizontal angles. It is used to measure the longitude and latitude of celestial bodies. It is one of the oldest astronomical instruments created by man. The device operates based on the principle of stereographic projection. The astrolabe is a predecessor of the modern planisphere.

The device on display was made at the Tula Arms Plant. In the 18th century, the Tula Arms Plant was recognized as the best state-owned arms manufacturer in Russia. The plant was under the close attention and patronage of the highest personages, and Tula craftsmen were famous for their skill and talent. This is why, the workshop “for the manufacture of mathematical, physical tools and instruments made of bone, wood, metal” was established at the factory. Grigory Alexandrovich Potemkin was the patron of this workshop. He appointed the Englishman Ferdinand Dovich head of the workshop.

From 1786 the workshop with its cutting-edge equipment produced the most precise measuring devices: sundials, astrolabes, protractors, and thermometers. They were distinguished by their optimized design, high quality of assembly, engravings and other decorative elements, while at the same time being sleek and elegant. To manufacture these devices, the factory used advanced metalworking machines, mechanisms and technologies. After the death of Ferdinand Dovich, Pavel Dmitrievich Zakhava was appointed mechanic of the workshop. From just 1812 to 1826, Zakhava was able to create several unique machines for drilling gun barrels, as well as machines for manufacturing and processing of bayonet tubes — which, among other things, contributed to the Tula Arms Plant becoming famous and well-acclaimed in Europe. Zakhava’s achievements at the Tula Arms Plant were held in high regard, and in 1833 he was awarded the Order of St. Vladimir, 3rd class. He is credited as the creator of many unique tools.