air at those depths, is acknowledged by everybody who has inquired into the state of those mines.

These causes, which are equivalent to a growing scarcity of silver (for a commodity may be said to grow scarcer when it becomes more difficult and expensive to collect a certain quantity of it) must, in time, produce one or other of the three following events. The increase of the expense must either, first, be compensated altogether by a proportionable increase in the price of the metal; or, secondly, it must be compensated altogether by a proportionable diminution of the tax upon silver; or, thirdly, it must be compensated partly by the one, and partly by the other of those two expedients.

This third event is very possible. As gold rose in its price in proportion to silver,