The value of a free-stone quarry, for example, will necessarily increase with the increasing improvement and population of the country round about it, especially if it should be the only one in the neighbourhood. But the value of a silver mine, even though there should not be another within a thousand miles of it, will not necessarily increase with the improvement of the country in which it is situated. The market for the produce of a free-stone quarry can seldom extend more than a few miles round about it, and the demand must generally be in proportion to the improvement and population of that small district; but the market for the produce of a silver mine may extend over the whole known world. Unless the world in general, therefore, be advancing in improvement and population, the demand for silver might not be at all increased by the improvement even of a large country in the neighbourhood of the mine. Even though the world in general were improving, yet if, in the course of its improvements, new mines should be discovered, much more fertile than any which had been known before, though the demand for silver would necessarily increase, yet the supply might increase in so much a greater proportion, that the real price of that metal might gradually fall; that is, any given quantity, a pound weight of it, for example, might gradually purchase or command a smaller and a smaller quantity of labour, or exchange for a smaller and a smaller quantity of corn, the principal part of the subsistence of the labourer. The great market for silver is the commercial and civilized part of the world. 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.