His first important work was a portrait of the racehorse "Antinous" (foaled 1758), for the Duke of Grafton.
Other horse-portraits were "Herod" (foaled 1758) for the Duke of Cumberland; "Snap" for a Mr. Latham; "Cardinal Ruff" for a Mr. Shafto; and "Bay Malton" for the Marquis of Rockingham.
Sartorius was a prolific and popular painter, and it is said that he produced more portraits of the famous race-horse "Eclipse" during the zenith of his fame than all other contemporary artists together (Bailys Magazine, January 1897, p. 23).
(1793–1795) are four excellent engravings from his works, including the famous racehorse "Waxey" (sired by the notable thoroughbred "Pot-8-Os").
His son John Nost Sartorius (1759–1828) was also a notable horse artist, the most distinguished of the family.