Thus, the trade of which the good ship Desire, of Salem, was the harbinger, grew into grand proportions; and for nearly two centuries poured a flood of wealth into New England, as well as no inconsiderable number of slaves. The General Court of Massachusetts recognized the trade as legal, imposing a duty of £4 per head on each negro sold in the province, with a drawback for those resold out of it, or dying in twelve months.[19] The weight of this duty is only evidence of a desire to raise revenue, and to discourage the settlement of numbers of negroes in Massachusetts; not of any disapproval of the traffick in itself, as a proper employment of New England enterprise. The government of the province preferred white servants, and was already aware of the unprofitable nature of African labour in their inhospitable climate; but the furnishing of other colonies with negroes was a favoured branch of commerce. The increase of negro slaves in Massachusetts during the seventeenth century was slow. But the following century changed the record. [Footnote 19: Idem, pp. 59, 60.] In 1720, Governor Shute states their numbers at two thousand. In 1754, a census of negroes gave four thousand five hundred; and the first United States census, in 1790, returned six thousand.[20] [Footnote 20: Moore, pp. 50, 51.] Meantime, the other maritime colonies of Rhode Island and Providence Plantations, and Connecticut, followed the example of their elder sister emulously; and their commercial history is but a repetition of that of Massachusetts. The towns of Providence, Newport, and New Haven became famous slave trading ports. The magnificent harbour of the second, especially, was the favourite starting-place of the slave ships; and its commerce rivalled, or even exceeded, that of the present commercial metropolis, New York. All the four original States, of course, became slaveholding.[21] [Footnote 21: Bancroft, vol. iii., ch. 24, does justice to the crimes of England against the Africans, and against her own colonies; but is absolutely silent touching the complicity of New England! And, as though this _suppressio veri_ were not enough, he proceeds to a studious _suggestio falsi_. Page 405th he says: "Of a direct voyage from Guinea to the coast of the United States, no journal is known to exist, though slave ships from Africa entered nearly every considerable harbour south of Newport." And, p. 410: "The English continental colonies, in the aggregate, were always opposed to the African slave trade." We have seen evidence, that Bancroft must have known that every American slaver which ever entered a port of the United States, was either from this same Newport, or other ports north of it. We shall see hereafter, that he must have known also, that Massachusetts was certainly not among that "aggregate" of the colonies which opposed the African slave trade. Yet, in this chapter, he endeavours expressly to produce that impression. See p. 408.]