days of antislavery agitation, when Cotton Mather, in his “Essays to Do Good,” spoke of the injustice of slavery in terms such that his little book had to be expurgated by the American Tract Society to accommodate it to the degenerate conscience of a later day, and when the town of Boston in 1701 took measures “to put a period to negroes being slaves.” Such endeavors after universal justice and freedom, on the part of the Christians of New England, thwarted by the insatiable greed of British traders