of its exchange value: higher the value cannot ascend; peculiar circumstances are required to raise it so high. This topic is happily illustrated by Mr. De Quincey. "Walk into almost any possible shop, buy the first article you see; what will determine its price? In the ninety-nine cases out of a hundred, simply the element D—difficulty of attainment. The other element U, or intrinsic utility, will be perfectly in-operative. Let the thing (measured by its uses) be, for your purposes, worth ten guineas, so that you would rather give ten guineas than lose it; yet, if the difficulty of producing it be only worth one guinea, one guinea is the price which it will bear. But still not the less, though U is inoperative, can U be supposed absent? By no possibility; for, if it had been absent, assuredly you would not have bought the article even at the lowest price. U acts upon you, though it does not act upon the price. On the other hand, in the hundredth case, we will suppose the circumstances reversed: you are on Lake Superior in a steam-boat, making your way to an unsettled region 800 miles a-head of civilization, and consciously with no chance at all of purchasing any luxury whatsoever, little luxury or big luxury, for the space of ten years to come. One fellow-passenger, whom you will part with before sunset, has a powerful musical snuff-box; knowing by experience the power of such a toy over your own feelings, the magic with which at times it lulls your agitations of mind, you are vehemently desirous to purchase it. In the hour of leaving London you had forgot to do so; here is a final chance. But the owner, aware of your situation not less than yourself, is determined to operate by a strain pushed to the very uttermost upon U, upon the intrinsic worth of the article in your individual estimate for your individual purposes. He will not hear of D as any controlling power or mitigating agency in the case; and finally, although at six guineas a-piece in London or Paris you might have loaded a waggon with such boxes, you pay sixty rather than lose it when the last knell of the clock has sounded, which summons
