The second, and more potent cause of development of the New England slave trade, was the commerce between those colonies and the West Indies. Each of the mother countries endeavoured to monopolize to herself all the trade and transportation of her own colonies. But it was the perpetual policy of Great Britain to intrude into this monopoly, which Spain preserved between herself and her colonies, while she jealously maintained her own intact. This motive prompted her systematic connivance at every species of illicit navigation and traffick of her subjects in those seas. The New England colonies were not slow to imitate their brethren at home; and although their maritime ventures were as really violations of the colonial laws of England, as of the rights of Spain, the mother country easily connived at them for the sake of their direction. The Spanish Main was consequently the scene of a busy trade during the seventeenth century, which was as unscrupulous and daring as the operations of the Buccaneers of the previous age. The only difference was, that the red-handed plunder was now perpetrated on the African villages instead of the Spanish, and for the joint advantage of the New England adventurers and the Spanish and British planters. At length, the treaty of Utrecht, in 1712, recognized this encroaching trade, and provided for its extension throughout the Indies.[16] New England adventure, as well as British, thus received a new _impetus_. The wine-staves of her forests, the salt fish of her coasts, the tobacco and flour of Virginia, were exchanged for sugar and molasses. These were distilled into that famous New England rum, which, as Dr. Jeremy Belknap, of Massachusetts, declared, was the foundation of the African slave trade.[17] The slave ships, freighted with this rum, proceeded to the coast of Guinea, and, by a most gainful traffick, exchanged it for negroes, leaving the savage communities behind them on fire with barbarian excess, out of which a new crop of petty wars, murders, enslavements, and kidnappings grew, to furnish future cargoes of victims; while they wafted their human freight to the Spanish and British Indies, Virginia, the Carolinas, and their own colonies. The larger number of their victims were sold in these markets; the less saleable remnants of cargoes were brought home, and sold in the New England ports. But not seldom, whole cargoes were brought thither directly. Dr. Belknap remembered, among many others, one which consisted almost wholly of children.[18] [Footnote 16: Bancroft, vol. iii., p. 231.] [Footnote 17: Moore's Hist. of Slavery in Mass., p. 6.] [Footnote 18: Moore, p. 68.]