Smithsonian iNSTiTtrTiON, 
Bureau of Ethnology, 
December 7, 1884. 
While engaged in tbe exploration of the Eocky Mountains I was 
urgently requested by the late Professor Henry, Secretary of the Smith- 
sonian Institution, to study the Indian tribes of tbe region, and espe- 
cially to collect vocabularies. In comi^liance with this request I culti- 
vated an acquaintance with the various Indian tribes met in that region, 
and usually a number of Indians traveled with me. I eventually became 
deeply interested in the study of the Indian languages of the United 
States, which interest increased as comparative studies were subse- 
quently made. 
From these rude beginnings I was led to explore a much wider field, 
and at last formed the plan of completing the classification of these 
languages, and especially of extricating the subject from much biblio- 
graphic confusion. During this time Mr. Pilling assisted me in collect- 
ing the literature of the subject, and at my request he undertook to 
prepare a bibliographj of the materials I was then using. But from 
year to year his work grew on his hands, until at last, at my earnest 
solicitation, he commenced the preparation of a bibliography of North 
American languages. To this task he has given the patient labor of 
years, and developed a genius for the work to which the present vol- 
ume is a monument. 
J. W. POWELL. 
