2. _Goods may be ranked by their relation to wants in time._ The relation in respect to time is measured by the period that must elapse before the utility of an agent results in, is converted into, gratification. No agent or influence intervening, a thing may yet be removed a long way from gratification. A tree may not be fitted to bear fruit for ten years to come. Meantime, there are many other possible uses for the tree: it may be used for fuel, or to make a canoe with which to catch fish, or to follow some other indirect method of production. Evidently the technical and time relations of goods are very different. The number of steps has no necessary relation to the time. A number of technical steps may be taken in half an hour, or a process of a single technical step may last a year. In the mechanic arts the technical relations are of primary significance, but in economics the time relations are mainly to be considered. 3. _Economic goods may be classified as immediately enjoyable goods and durable agents._ Enjoyable goods are goods in a final form, producing gratification or just ready to give gratification the next moment, as the cool draft of air made by a fan on a hot day, the cup of coffee steaming on the table. [Sidenote: Enjoyable goods and durable agents] Many goods of just the same form as the foregoing may not be affording current gratification (except that afforded by thrift and forethought), but are kept because later they will gratify a more intense want or gratify a want better. Apples and potatoes are kept in a cellar so that their use is distributed throughout the winter; cider and wine are kept till they get a quality that appeals more to the palate. Coal, wood, and stocks of goods, are thus kept in the form of enjoyable goods, destined to be physically destroyed when at length they yield a gratification. Evidently they must be storing up meantime a certain additional utility, for otherwise there would be no reason why they should be kept for the future. Such goods as these are sometimes called unripened consumption goods, but until ripened they bear in part the character of durable agents. Abiding sources of economic enjoyments are called durable agents. The inhabited house is a source of continued gratification in each moment's shelter it affords; but, further, it is the durable source of a series of future uses, as yet unripened. The hammer, the hoe, the tree, the field may all be considered as agents to secure consumption goods. Some of these are but one step removed from direct gratification, as the hoe helping the gardener to get food for his own use. Other agents are bound by many technical links to the ultimate gratification. [Sidenote: Degrees of durableness]