But some of the metals, having value in small bulk, salability, cognizability, and durability, step by step displaced other forms of money. Finally, money must be made of a material easy to divide and unite. It is a great convenience in small transactions to be able to represent a fractional value by a small coin. The money material thus, likewise, is easily shifted to and from its money use. It is a very poor money that has not this quality, yet a thing may serve for money in larger transactions without it. Cattle, slaves, and land have been thus used, although they answer in a very rough way these fundamental requirements of the money material. [Sidenote: Industrial changes affect the convenience of certain money forms] 4. _The changing material and industrial conditions of society change the kind of money that is used._ The money use, as has just been shown, is a resultant of a number of different motives in men. Things that have the highest claim to fitness for money with a people at one stage of development would have a low claim at another. As each of these stages is passed, the thing used as money either increases or decreases in its fitness. The final choice depends on the resultant of all the advantages. The use of a material may become more general or less so. Shells used for ornament in poor communities cease to be so used in a higher state of advancement, and thus their salability ceases. Furs, used at some stage of development as money in all northern climes, cease to be generally marketable when the fur-bearing animals are nearly killed off and the fur trade declines. Tobacco was at one time in Virginia a great staple. Merchants were always ready to take it, and its market price was known by all; but as it ceased to be the almost exclusive product of the province, it lost the knowableness and marketability it had before. In agricultural and pastoral communities where every one had a share in the pasture, cattle were a fairly convenient form of money, but to-day would be a most inconvenient one; a city merchant exchanging goods for Poland China pigs and Texas steers would envy the proverbial owner of a white elephant. [Sidenote: The proved fitness of gold and silver as money]