“So,” observed Charles, “if a mine should ever be dug so deep that the air is not fresh at the bottom where the miners work, the owner of the mine would be very glad to buy air of any one who could convey it down by a machine. Such an one would be wise to charge so much a gallon for the fresh air he supplied, to pay for the labour and expense of his machine, and for the trouble of working it.” Marguerite then mentioned that she once staid in a small country town during a drought. There was no reservoir of water, and all the pumps and cisterns were dry. The poor people went out by night into the neighbouring country, and watched the springs; and any one who was fortunate enough to obtain a gallon of fresh water was well paid for it. The price rose every day, till at last one woman gave a calf for a pailfull of water, hoping to save her cow, it being certain that both must die without this supply. “And did she save her cow?” “Yes. While the woman was anxiously sitting up in bed, planning what she should change away next, she fancied there was a different feel in the air; and on looking out of the window, she found the sky covered with black clouds; and before morning, the trade in water was over. There was nobody to give a doit for a cistern-full.” “It was just so with me,” observed Charles, “when I was besieged in the cellar. I was parched with thirst, and would have given a pipe of my best wine to any one who would have let me down a quart of water through the trap-door. Three hours after, I myself threw hundreds of gallons on the fire at the guard houses, when the order was given to take them down in an orderly way; and I did not consider such use of the water any waste. So much for the value which is given by scarcity.” “But, papa, though things are more valuable to people when there is a scarcity of them, the people are less rich than they were before. That seems to me very odd.” “Because you have been accustomed to consider value and wealth as the same things, which they are not. Our wealth consists in whatever is valuable in use as well as in exchange. Owing to the storm of last year, I have less wealth in my possession now than I had then, though what I have may, perhaps, exchange for more wealth still. I have as much furniture, and as many clothes and luxuries, and as much money; but I have fewer growing vines, and much less wine. If I were to use up my own grapes and wine instead of selling them, they would last a much shorter time than my stock of the former year would have lasted. So I have less wealth in possession. But the value of wine has risen so high, in consequence of scarcity, that I can get as much now of other things in exchange for a pint, as I could, fourteen months ago, in exchange for a gallon.” “But that is partly because the wine is older. Mr. Steele is very particular about the wine being old, and he pays you much more, he told me, the longer it has been kept.”