Born February 14, 1812 (or 1817), in Sparta, N.Y. Studied with his brother Frederick and with Thomas Cummings. Lived in New York, 1831–38. Served as "portrait and botanical artist" on the Wilkes around-the-world expedition, 1838–42. Lived in Washington, D.C., 1842–46. Prepared over half the illustrations for Wilkes's six-volume Narrative of the United States Exploring Expedition (1844–-45). Married Elizabeth Hill Kennedy of Alexandria, 1845. Died January 5, 1846, in Washington, D.C.
Andrew J. Cosentino and Henry H. Glassie The Capital Image: Painters in Washington, 1800–1915 (Washington, D.C.: Smithsonian Institution Press for the National Museum of American Art, 1983)
Alfred T. Agate learned the art of miniature painting from the artist Thomas Seir Cummings. He spent almost a decade working in New York, exhibiting several times at the National Academy of Design. In 1838 he joined the Scientific Corps of the United States Exploring Expedition as a portraitist and botanical artist. He spent four years traveling around the world, mapping the coast of Oregon, documenting hundreds of islands in the Pacific, and collecting more than sixty thousand plant and bird specimens. On his return, Agate settled in Washington, D.C., and prepared his drawings for the expedition’s extensive report. The artifacts and specimens brought back later became the founding collection of the Smithsonian Institution.