In the year 1825, Humboldt estimated the entire population of Brazil at about 4,000,000; of this number he calculated that 920,000 were whites, 1,960,000 negroes, and 1,120,000 mixed races and native Indians. Here the proportion of the coloured races to the white is about three to one. Later estimates give an entire population of 5,000,000; and the proportion of the coloured race to the whites stands as four to one. It was supposed at the time when the law was passed to render illegal the introduction of new slaves, that the proportional number would speedily decline. Had this law been strictly observed, such would, no doubt, have been the case, as it is well known that the number of births falls far short of the deaths among the slave population in Brazil. This does not arise from their ill usage, as some writers have supposed, but from the well-known fact that a greater proportion of males than of females has at all times been introduced to the country. On some estates in the interior the proportion of females to males is often as low as one to ten. In the Diamond District, in particular, females are very scarce. The law, however, has not been attended to, and the consequence of incessant introduction is, that the number of slaves in the country has not declined. During the five years which I spent in Brazil, I have good reason for believing that the supply was always nearly equal to the demand, even in the most distant parts of the empire. Notwithstanding the vigilance of the cruisers both on the coast of Brazil and that of Africa, it was well known to every one in Rio, that cargoes of slaves were regularly landed even within a few miles of the city; and during several voyages which I have made in canoes and other small craft along the shores of the northern provinces, I have repeatedly seen cargoes of from one to three hundred slaves landed, and have heard of others. There are many favourite landing-places between Bahia and Pernambuco, particularly near the mouth of the Rio San Francisco. Again and again, while travelling in the interior, I have seen troops of new slaves of both sexes, who could not speak a single word of Portuguese, varying from twenty to one hundred individuals, marched inland for sale, or already belonging to proprietors of plantations. These bands are always under the escort of armed men, and those who have already been bought, are not unfrequently made to carry a small load, usually of agricultural implements. There is no secrecy made of their movements, nay, magistrates themselves are very often the purchasers of them. It is likewise well known that the magistrates of those districts where slaves are landed, receive a certain per-centage on them as a bribe to secrecy. The high price which they bring in the market, is a very great temptation to incur the risk of importing them. It is said that if only one cargo be saved out of three, that one will cover the whole expenses, and leave a handsome profit besides.