§ 3. Indirect uses, consumptive and durative. We turn now to illustrations of indirect uses which are consumptive or durative in varying degrees (and, of course, either present or future). Many of thg,objects that yield indirect uses yield at the same time direct ones; indeed, this is the rule rather than the exception. Other examples of consumptive goods used indirectly are : the oil giving light in the factory, the ice in the refrigerator. These are present uses and are also capable of direct use. The oil in tank, and the ice in the icehouse contain future consumptive uses. A dynamo producing elec tricity is yielding a present durative use and, as it is capable of continuing to yield similar uses, it contains also future dura tive uses. Further examples are most tools, implements, and machines, and all houses, lands, engineering works, and all transportation agencies that are used both directly for pas senger service, and indirectly in carrying freight.
§ 4. The single consumptive use. The distinction between consumptive and durative uses should be kept clearly apart from that between direct and indirect uses. As a matter of fact, directness of use is essentially a technical rather than an economic quality. It is equally important to keep the matter of the "timeliness" of a use distinct from either "directness" or "consumptiveness." In connection with timeliness arises the very subtle problem of capital-value, which will be discussed at some length in Part IV of this book. Wrapped up with the question of durability is a problem to which we must give earlier consideratiOn—the problem of usance-value. This will be taken up in Chapter 13. Our immediate task, however, is a somewhat further consideration of the nature of the distinc tion between consumptive and durative uses.
We have been employing the words consumptive and dura tive as contrasted terms. Strictly speaking, however, con sumptive and durative uses shade into each other by almost imperceptible gradations. Even most of the more fleeting uses continue through an appreciable period of time. The great majority of goods in which man is interested are more or less durable in character. The things which may reasonably be said to have consumptive uses—that is, things which are con sumed at a single use—are relatively few, tho absolutely nu merous and important. Food, for example, is consumed at a single use ; illuminants and fuel can be used but once ; cut flowers quickly wither and fade. The materials of which these things were composed are dissipated in sewage, garbage, rub bish, dust, ashes, carbonic acid gas, etc., and can be reassembled —if at all—only with difficulty. • § 5. No economic goods absolutely durable. At the other
end of the scale are things which render their services for an extremely long period of time. All earthly things, however, wear out, change, or decay. Whenever man's hand is with held, nature takes possession of his work, regardless of his purposes. Dust gathers on unused clothes, and moths burrow in them. Shut up a house, and windows are shattered, roofs leak, and vermin swarm. To close a factory is to hasten the time when buildings and machinery will be piled upon the rubbish heap. The most magnificent and solid works of man have crumbled under the finger of time. The earth is strewn with ruins of gigantic engineering works, aqueducts, canals, temples, and monuments, whose restoration would be no less a task than was their first building. Everywhere vigilance and repairs are the conditions of continued uses of wealth. There are, thus, no economic goods which as usable wholes are abso lutely durable. When we divide uses into those which are con sumptive and those which are durative, we mean simply that the duration of the goods yielding the former is relatively brief, whereas the latter endure through a relatively long period of time. The line of demarcation between the two is not absolute or sharp.
§ 6. Inevitable depreciation. Changes go on in the sub stance of things which cannot be prevented by any attention to repairs. The wood in a framework will decay, the metals crystallize. There is also an unpreventable wear of parts that can not be replaced without replacing the whole machine. It is the aim of the modern manufacturers to make machines like the wonderful one-horse shay, every part of equal durability. The development in America of the system of "interchangeable parts" has greatly simplified and cheapened repairs, and has lengthened the working life of machines; nevertheless they go at last to the scrapheap. This general depreciation appears to be nearly avoided in large factories where there is serial re placement of the parts, but occasionally some invention or some improvement of process necessitates an almost completely new equipment. An old man said to me when I was a boy : "I built this house and have lived in it forty years; it was well built, has been repainted regularly, has never been allowed to leak a drop, and it is as good as it ever was. I see no rea son why it could not be kept to eternity if always kept in repair." But the same could not be said of the house now. There is a termination of the use-bearing power of nearly all kinds of goods, by this natural decay or by technical progress, and they have to be replaced by new stuff and by new forms.