Franz Boas (1858-1942) was born in Germany where he studied physics and geography. After an expedition to Baffin Island (1883), where he conducted ethnographic work among the Eskimo, Boas's lifework changed. In 1886 he worked among American Indian tribes in British Columbia before his permanent move to America in 1888. This eventually lead to a professorship at Columbia University in 1899 which he held until his retirement in 1936 (Lowie 1937:128-129). Boas was a pioneering anthropological field worker and based many of his concepts on experiences gained while working in the field. He insisted that the fieldworker collect detailed cultural data, learn as much of the native language as possible, and become a part of the native society in order to interpret native life "from within." Boas hoped to document accurately aboriginal life and to alleviate the bias of "romantic outsiders." He used the technique of recording the reminiscences of informants as a valuable supplement to ethnography (Lowie 1937:132-135). He believed the cultural inventory of a people was cumulative and was the result of diffusion. Boas envisioned culture traits as being part of two historical processes, diffusion and modification (Hatch 1973:57-58).