"How so?" said Rollo.
"Why, the money that you will pay for it will produce about fifty cents a year, if you keep it at interest; and of course, if you buy a chain with the money, you stop all that income."
"Yes," said Rollo, "I understand that for the fifty cents: and now for the other ten. You said sixty cents."
"Why, the chain will be gradually wearing out all the time, while you use it," said Mr. George, "and I estimated that it would lose about ten cents a year. That makes up the sixty."
"Yes," said Rollo, "I suppose it would."
"You see," continued Mr. George, "that the little links and rings, where the chief wear comes, will gradually become thinner and thinner, and at last the time would come when you could not use it for a chain any longer. You would then have to sell it for old gold; and for that purpose it would not be worth, probably, more than half what you now give for it.
"So you see," continued Mr. George, "you would lose the interest on the money you pay for the chain every year; and besides that, you would lose a portion of the chain itself. When you have money safely invested at interest, you have the interest every year, and at the end of the term you have your capital restored to you entire. But in such a purchase as this, you are sure, in the end, to sink a portion of it by wear, and tear, and depreciation; and this circumstance ought always to be taken into account."
"Yes," said Rollo; "that is very true."
"Making such a calculation as this," continued Mr. George, "will often help us determine whether it is wise or not to make a purchase. The question is, whether you would get as much pleasure from the possession and use of this chain as sixty cents a year would come to."