The early period at which Mr. Schoolcraft entered the field of observation in the United States as a naturalist; the enterprise he has from the outset manifested in exploring the geography and geology of the Great West; and his subsequent researches as an ethnologist, in investigating the Indian languages and history, are well known to the public, and may be appropriately referred to as the grounds of the present design, in furnishing some brief and connected sketches of his life, family, studies, and literary labors. He is an example of what early and continued zeal, talent, and diligence, united with energy of character and consistent moral habits, may accomplish in the cause of letters and science, by the force of solitary application, without the advantage of hereditary wealth, the impulse of patronage, or the prestige of early academic honors. Ardent in the pursuit of whatever engaged his attention, quick in the observation of natural phenomena, and assiduous in the accumulation of facts; with an ever present sense of their practical and useful bearing--few men, in our modern history, have accomplished so much, in the lines of research he has chosen, to render science popular and letters honorable. To him we are indebted for our first accounts of the geological constitution, and the mineral wealth and resources of the great valley beyond the Alleghanies, and he is the discoverer of the actual source of the Mississippi River in Itasca Lake.