If, by the general progress of improvement, the demand of this market should increase, while, at the same time, the supply did not increase in the same proportion, the value of silver would gradually rise in proportion to that of corn. Any given quantity of silver would exchange for a greater and a greater quantity of corn; or, in other words, the average money price of corn would gradually become cheaper and cheaper. If, on the contrary, the supply, by some accident, should increase, for many years together, in a greater proportion than the demand, that metal would gradually become cheaper and cheaper; or, in other words, the average money price of corn would, in spite of all improvements, gradually become dearer and dearer. But if, on the other hand, the supply of that metal should increase nearly in the same proportion as the demand, it would continue to purchase or exchange for nearly the same quantity of corn; and the average money price of corn would, in spite of all improvements, continue very nearly the same. These three seem to exhaust all the possible combinations of events which can happen in the progress of improvement; and during the course of the four centuries preceding the present, if we may judge by what has happened both in France and Great Britain, each of those three different combinations seems to have taken place in the European market, and nearly in the same order, too, in which I have here set them down. _Digression concerning the Variations in the value of Silver during the Course of the Four last Centuries._ _First Period._--In 1350, and for some time before, the average price of the quarter of wheat in England seems not to have been estimated lower than four ounces of silver, Tower weight, equal to about twenty shillings of our present money. From this price it seems to have fallen gradually to two ounces of silver, equal to about ten shillings of our present money, the price at which we find it estimated in the beginning of the sixteenth century, and at which it seems to have continued to be estimated till about 1570.