Thus our trade must, till that country becomes as fully peopled as England (that is for centuries to come) be continually increasing, and with it our naval power; because the ocean is between us and them, and our ships and seamen must increase as that trade increases.--The human body and the political differ in this; that the first is limited by nature to a certain stature, which, when attained, it cannot ordinarily exceed: the other, by better government and more prudent police, as well as by change of manners and other circumstances, often takes fresh starts of growth, after being long at a stand; and may add tenfold to the dimensions it had for ages been confined to. The mother, being of full stature, is in a few years equalled by a growing daughter: but in the case of a mother-country and her colonies, it is quite different. The growth of the children tends to increase the growth of the mother, and so the difference and superiority is longer preserved. Were the inhabitants of this island limited to their present number by any thing in nature, or by unchangeable circumstances, the equality of population between the two countries might indeed sooner come to pass: but sure experience, in those parts of the island where manufactures have been introduced, teaches us; that people increase and multiply in proportion as the means and facility of gaining a livelihood increase; and that this island, if they could be employed, is capable of supporting ten times its present number of people. In proportion, therefore, as the demand increases for the manufactures of Britain, by the increase of people in her colonies, the number of her people at home will increase; and with them, the strength as well as the wealth of the nation. For satisfaction in this point, let the reader compare in his mind the number and force of our present fleets, with our fleet in Queen Elizabeth's time[39], before we had colonies. Let him compare the ancient, with the present state of our towns on or near our western coast (Manchester, Liverpool, Kendal, Lancaster, Glasgow, and the countries round them) that trade with any manufacture for our colonies (not to mention Leeds, Halifax, Sheffield, and Birmingham,) and consider what a difference there is in the numbers of people, buildings, rents, and the value of land and of the produce of land; even if he goes back no farther than is within man's memory. Let him compare those countries with others on the same island, where manufactures have not yet extended themselves; observe the present difference, and reflect how much greater our strength may be (if numbers give strength) when our manufacturers shall occupy every part of the island where they can possibly be subsisted.