Commerce rather than industrialism or agriculture is the distinctive feature of English economy during the seventeenth and first half of the eighteenth century. By means of newly developed trade-routes, the East and the West were tapped for such products as tobacco, tea, coffee, cocoa, sugar, rum, spices, oranges, lemons, raisins, currants, silks, cotton, rice, and others with which England had previously somehow or other dispensed; and the principal bone of contention was the carrying trade of the world. Shipbuilding was the most famous English industry; and when Peter the Great visited England, he spent most of his time in the Deptford yards. For some of these imports England paid by her services as carrier; and so far as India was concerned it was a case of robbery rather than exchange. But exports were more and more required to pay for the ever-increasing imports. It is impossible to state categorically either that the imports provoked the exports or the exports the imports; for the supply creates the demand as much as the demand creates the supply. There can have been no conscious demand for tobacco in England before any Englishman had smoked a pipe; and when an English merchant in Elizabeth's reign took a thousand kerseys to Bokhara, he did so without waiting for an order. Both exports and imports, however, can only develop together; the dimensions to which English commerce had attained by Walpole's time involved exports as well as imports; and the exports could not have been provided without developing English industries. In particular, England had to export to the colonies because the colonies had by the Navigation Acts to export to England; and Walpole's abolition or reduction of duties on colonial produce illustrated and encouraged the growth of this trade. In return for colonial tobacco, rice, cotton, sugar, England sent chiefly woollen and afterwards cotton manufactures. These woollens had long been manufactured on the domestic system in the sheep-rearing districts of England, particularly Yorkshire; many a cottage with its four acres for farming had also its spinning-wheel, and many a village its loom; and the cloth when finished was conveyed by pack-horses or waggons to the markets and fairs to be sold for export or home consumption. But between 1764 and 1779 a series of inventions by Arkwright, Hargreaves, and Crompton, transformed the simple spinning-wheel into an elaborate machine capable of doing the work of many spinners; and once more an advance in national productivity was made at the expense of the individual workers who took to breaking the machines to stop their loss of work.