In 1893 and 1894 Fassett was engaged in chart-making on the Northern fur seal and fishery investigations carried out by the United States Fish Commission on USFC Albatross.
[2] His duties expanded to include photography using a glass-plate camera on the Alaskan salmon research cruises conducted from 1894 to 1897.
[3] As captain's clerk on the 1889-1900 Pacific cruise of USFC Albatross conducted by the United States Fish Commission, Fassett was engaged in chart making[4] and photography; recording people, communities and scenes during this voyage using a glass-plate camera.
The ship visited Japan, departing Yokohama on 2 June 1900 to visit Hakodate, Japan, and Kamchatka, north of the Aleutian Islands, and collected biological specimens in the North Pacific and into the Bering Sea and ultimately returned to San Francisco on 30 October 1900 after a cruise of 14 months.
By 1907 Fassett is titled in official publications as a fishery expert,[6] and participated in the Albatross Philippine Expedition,[7] from 16 October 1907 to 4 May 1910, conducted by the United States Bureau of Fisheries and the Smithsonian Institution, under Commander Marbury Johnston and Hugh McCormick Smith, Deputy Commissioner of Fisheries, Director of the Expedition.