) In 1803 he was appointed professor at
Moscow University. He participated as a ship's doctor, marine biologist and expedition artist on the frigate Nadezhda in the
first Russian circumnavigation of the globe during 1803-1806 under
Adam Johann von Krusenstern. The Nadezhda departed from
Kronstadt on the Baltic Sea, with Tlesius joining the expedition at Copenhagen; included among his baggage were a violin and viola, which he played on the voyage. The Nadezhda sailed past the
Canary Islands and Brazil, around Cape Horn and across the Pacific Ocean to Japan, stopping at the
Marquesas and
Hawaiian islands, and also at
Kamchatka. After visiting Japan, the Nadezhda set off towards Alaska, then sailed past China to the Indian Ocean, around Africa and back to the Baltic. Tilesius made numerous sketches and watercolors during the trip, particularly after the official artist departed in Japan. Honors Tilesius received on his return included being made a knight in the
Order of St. Vladimir, corresponding membership of the
Imperial Academy of Sciences, and a lifetime pension of 300
rubles per year. His illustrated report on the expedition appeared in 1814. However, he did not win public recognition like his contemporary,
Alexander von Humboldt. ==Later life==