Though the wealth of Great Britain has increased very much since the establishment of the Act of Navigation, it certainly has not increased in the same proportion as that of the colonies. But the foreign trade of every country naturally increases in proportion to its wealth, its surplus produce in proportion to its whole produce; and Great Britain having engrossed to herself almost the whole of what may be called the foreign trade of the colonies, and her capital not having increased in the same proportion as the extent of that trade, she could not carry it on without continually withdrawing from other branches of trade some part of the capital which had before been employed in them as well as withholding from them a great deal more which would otherwise have gone to them. Since the establishment of the Act of Navigation, accordingly, the colony trade has been continually increasing, while many other branches of foreign trade, particularly of that to other parts of Europe, have been continually decaying. Our manufactures for foreign sale, instead of being suited, as before the Act of Navigation, to the neighbouring market of Europe, or to the more distant one of the countries which lie round the Mediterranean Sea, have, the greater part of them, been accommodated to the still more distant one of the colonies, to the market in which they have the monopoly rather than to that in which they have many competitors. The causes of decay in other branches of foreign trade, which, by Sir Matthew Decker and other writers, have been sought for in the excess and improper mode of taxation, in the high price of labour, in the increase of luxury, etc., may all be found in the overgrowth of the colony trade. The mercantile capital of Great Britain, though very great, yet not being infinite, and though greatly increased since the Act of Navigation, yet not being increased in the same proportion as the colony trade, that trade could not possibly be carried on without withdrawing some part of that capital from other branches of trade, nor consequently without some decay of those other branches.

England, it must be observed, was a great trading country, her mercantile capital was very great and likely to become still greater and greater every day, not only before the Act of Navigation had established the monopoly of the colony trade, but before that trade was very considerable. In the Dutch war, during the government of Cromwell, her navy was superior to that of Holland; and in that which broke out in the beginning of the reign of Charles II, it was at last equal, perhaps superior, to the united navies of France and Holland. Its superiority, perhaps, would scarce appear greater in the present times; at least if the Dutch navy was to bear the same proportion to the Dutch commerce now which it did then. But this great naval power could not, in either of those wars, be owing to the Act of Navigation. During the first of them the plan of that act had been but just formed; and though before the breaking out of the second it had been fully enacted by legal authority, yet no part of it could have had time to produce any considerable effect, and least of all that part which established the exclusive trade to the colonies. Both the colonies and their trade were inconsiderable then in comparison of what they are now. The island of Jamaica was an unwholesome desert, little inhabited, and less cultivated. New York and New Jersey were in the possession of the Dutch: the half of St. Christopher's in that of the French. The island of Antigua, the two Carolinas, Pennsylvania, Georgia, and Nova Scotia were not planted. Virginia, Maryland, and New England were planted; and though they were very thriving colonies, yet there was not, perhaps, at that time, either in Europe or America, a single person who foresaw or even suspected the rapid progress which they have since made in wealth, population, and improvement. The island of Barbadoes, in short, was the only British colony of any consequence of which the condition at that time bore any resemblance to what it is at present. The trade of the colonies, of which England, even for some time after the Act of Navigation, enjoyed but a part (for the Act of Navigation was not very strictly executed till several years after it was enacted), could not at that time be the cause of the great trade of England, nor of the great naval power which was supported by that trade. The trade which at that time supported that great naval power was the trade of Europe, and of the countries which lie round the Mediterranean Sea. But the share which Great Britain at present enjoys of that trade could not support any such great naval power. Had the growing trade of the colonies been left free to all nations, whatever share of it might have fallen to Great Britain, and a very considerable share would probably have fallen to her, must have been all an addition to this great trade of which she was before in possession. In consequence of the monopoly, the increase of the colony trade has not so much occasioned an addition to the trade which Great Britain had before as a total change in its direction.