The Journal of Negro History, Volume 2, 1917 is a Book of Social Science. The book describes the Negro History. Slavery in Africa has existed from time immemorial, having risen, not from any outside influence, but from the very nature of the local conditions. The three circumstances necessary to develop slavery are: First, a country favored by the bounty of nature. Unless nature yields generously it is impossible for a subject class to produce surplus enough to maintain their masters. Where nature is niggardly, as in many hunting districts, the labor of all the population is required to meet the demands of subsistence. Second, a country where the labor necessary to subsistence is, in some way, very disagreeable. In such cases every man and woman will seek to impose the task of production upon another.