Amongst the inhabitants of the Spanish colonies, the fourth rank was assigned to the _negroes_ pure and simple. They were in several settlements employed chiefly in domestic service. Their superior physical strength, as well as their favour with their masters, gave them an ascendancy over the natives, whom they were wont to treat with such insolence and scorn, that an implacable antipathy arose between the two races. This antipathy, which originated from accidental causes, was no sooner perceived than it was sedulously fomented, great precautions being taken to prevent anything which might form a bond of union between the two races. Last of all, in the order of society, came the unfortunate native Indians, who had been so ruthlessly dispossessed of all their natural rights. Due regulations determined the nature and extent of the services which these were required to perform, and likewise the amount of the annual tax imposed upon all males between the ages of fifteen and fifty. When the native was an immediate vassal of the Crown, three-fourths of the tax, which may have been on an average about four shillings a head, were paid into the royal treasury. When he formed part of an _encomienda_, a like proportion belonged to the holder of the grant. As the original _encomiendas_ were only granted for two lives, they then reverted to the sovereign. The benefit of the labour of the natives in like manner belonged either to the Crown or to the holder of the grant. They were compelled to assist in works of necessity, such as the culture of corn, tending cattle, forming roads, bridges, &c.; but they could not be constrained to labour for the furtherance of objects of personal gratification or commercial profit. For the purpose of service in the mines they were called out in successive divisions, called _mitas_, in which each person took his turn. In _Peru_ each _mita_ could not exceed a seventh part of any inhabitants of a district, and was detained at service in the mines for six months at a time. Whilst engaged in this service, however, each labourer was duly paid, receiving from two to four shillings a day; and, after a time, a humane regulation was introduced, forbidding the deportation of the natives of the plains to the elevated regions. No Indian residing more than thirty miles from the mine might be assigned to the _mita_ employed in it.