But things arrange themselves thus: It is soon found that one of the things which are being exchanged is easier to carry than the rest, and perhaps lasts longer and also can be easily used in small or large amounts. For instance, in the case of our three producers, John, William and Robert, _wheat_ might easily appear in this character. People always want wheat sooner or later. It keeps well. It is not very difficult to transport, and you can divide it into quite small amounts, or lump it up in large amounts. So the chances are that when any of the three wanted to benefit by getting rid of some of his surplus produce he would get into the habit of taking _wheat_ in exchange, even if he did not want it for the moment. For he would say to himself: “I can always keep it by me and then exchange it against somebody else’s produce when that somebody else happens to want wheat”. Soon you would find each one of the three would be keeping a little wheat by him for the purpose of saving tiresome journeys to effect complicated double exchanges, and the wheat so used by all three of them would be in effect =MONEY=. It would be used as a common medium of exchange to facilitate the disposal of goods one against the other, without the elaborate business of making special barters, after long search. Mankind has found, in most cases, that where a very large number of articles were being exchanged _two_ in particular naturally lent themselves to this particular use, and those two were GOLD and SILVER. They have also used bronze, and even iron and in some places rare shells, and all sorts of other things. But gold and silver came to be for nearly all mankind, and are now for all civilised mankind, the objects which most naturally are used as money. The reason for this is as follows: The thing which naturally becomes money out of all the things that are exchanged will be that which best combines a certain number of qualities, some of which we have already mentioned, and of which here is a list. 1. It must be portable, that is, a large weight of it must take up little room, so that quite considerable values can be taken easily from place to place--for money has to be always moving from one to another to effect purchases and sales. 2. It must be easily divisible, for one is always wanting to use it in all sorts of amounts, very little and very large. 3. It must keep. That is, it must not deteriorate quickly, or it would have very little use as Money. 4. It must be of an even quality, so that, wherever you come across it, you may count on its being pretty well always the same, and therefore weight for weight of the same value. 5. It must be more or less stable in value. It would be difficult to use as money some object which was very plentiful at one moment and suddenly scarce at another; very cheap this year, and very dear next year--such as are, for instance, agricultural products depending upon the season.