Naturalist; born in Westfield, Mass., Jan. 9, 1744; was a pupil of Silas Deane (q. v.) when the latter was a school-master.
His early education was not extensive.
Apprenticed to a mechanic, he ran away, in debt to his master, and went to sea; but returning with means, he compensated his employer.
Again he went to sea; settled in Guiana, South America, as a physician, in 1763, and afterwards made his residence in London, where, in 1769, he published a Natural history of Guiana.
He became a Fellow of the Royal College of Physicians, and Fellow of the Royal Society.
While Franklin was in England on a diplomatic mission, Dr. Bancroft became intimate with him; and through the influence of the philosopher became a contributor to the philosopher became a contributor to the Monthly review.
He was suspected by the British government of participation in the attempt to burn the Portsmouth dock-yards, and he fled to Passy, France.
Soon afterwards he met Silas Deane, his