第601页 / 共2651页

These different sorts of rude produce may be divided into three

classes. The first comprehends those which it is scarce in the

power of human industry to multiply at all. The second, those

which it can multiply in proportion to the demand. The third,

those in which the efficacy of industry is either limited or

uncertain. In the progress of wealth and improvement, the real

price of the first may rise to any degree of extravagance, and

seems not to be limited by any certain boundary. That of the

second, though it may rise greatly, has, however, a certain

boundary, beyond which it cannot well pass for any considerable

time together.