Still a further and future exchange was contemplated by both parties at the time of making this exchange, and as a silent part of it. A takes what is now his own wheat, and B takes as an equivalent for what was his wheat a right to demand of A in six months an equivalent for the present equivalent (the pledge) for the sake of which B rendered the wheat. The note of hand is the evidence of this pledge, and it belongs absolutely to B. It is his property. He may keep it till maturity and then sell it to A for its face, or he may sell it at once to a bank for its face less the discount for six months. Discount is the difference between the face and the present price of a note of hand. The first peculiarity, then, of Credit is, that it always involves the element of future time. But it involves this secondarily, and not primarily. In other words, a present equivalent is always rendered by both parties in every commercial transaction; but the present equivalent in the case of a credit transaction is the right to demand something of somebody sometime in the future. This distinction is very important, as we shall see clearly when we come to treat of Banking, though it is generally ill-understood at present. Valuables, when they exchange at all, exchange once for all. But there is one kind of valuables, namely, claims, which, when subject to exchange, imply and require another and a future exchange, not necessarily between the parties to the first exchange, but between _some_ two parties; and not, speaking strictly, to _consummate_ the first exchange, because that took and gave its own satisfactory equivalents; but, as involving both time and trust, the credit sale must in the nature of things be followed by another sale of one of the three kinds.