What a bank can with propriety advance to a merchant or undertaker of any kind, is not either the whole capital with which he trades, or even any considerable part of that capital; but that part of it only which he would otherwise be obliged to keep by him unemployed and in ready money, for answering occasional demands. If the paper money which the bank advances never exceeds this value, it can never exceed the value of the gold and silver which would necessarily circulate in the country if there was no paper money; it can never exceed the quantity which the circulation of the country can easily absorb and employ.
When a bank discounts to a merchant a real bill of exchange, drawn by a real creditor upon a real debtor, and which, as soon as it becomes due, is really paid by that debtor; it only advances to him a part of the value which he would otherwise be obliged to keep by him unemployed and in ready money, for answering occasional demands. The payment of the bill, when it becomes due, replaces to the bank the value of what it had advanced, together with the interest. The coffers of the bank, so far as its dealings are confined to such customers, resemble a water-pond, from which, though a stream is continually running out, yet another is continually running in, fully equal to that which runs out; so that, without any further care or attention, the pond keeps always equally, or very near equally full. Little or no expense can ever be necessary for replenishing the coffers of such a bank.
A merchant, without over-trading, may frequently have occasion for a sum of ready money, even when he has no bills to discount. When a bank, besides discounting his bills, advances him likewise, upon such occasions, such sums upon his cash account, and accepts of a piece-meal repayment, as the money comes in from the occasional sale of his goods,