He was chief of the Bureau of Ordnance in 1893-1897.
In 1757 he was made lieutenant-general of the ordnance, and transferred to a fourth colonelcy.
The Duma endorsed this all but unanimously, and as the result the Grand-dukes Peter and Sergius resigned their posts of inspector-general of Engineers and Ordnance respectively, and the Grand-duke Nicholas his chairmanship of the Committee of National Defence.
In 1741 a school of instruction for the military branch of the ordnance was established here.
At the Charlestown navy-yard (1800) there are docks, manufactories, foundries, machine-shops, ordnance stores, rope-walks, furnaces, castingpits, timber sheds, ordnance-parks, ship-houses, &c. The famous frigate " Independence " was launched here in 1814, the more famous " Constitution " having been launched while the yard was still private in 1797.