tion on the earth's surface, it is, except for rare catastrophes, such as earthquakes, volcanic eruptions, and floods, well-nigh everlasting in the view of mortal man But it is something more than mere location that makes land useful, whether used for agricultural, forestry, quarrying, or mining purposes. Used for these, and even for residence and commercial pur poses, it is quite capable of being used up and destroyed as a use-bearer. It is in large part not nature but man's art in the careful use of land that enables it to be looked upon as an indestructible agent, yielding a permanent series of uses. A form of contract came to be used in letting the land for hire, that called for the return of the land in as good condition as when it was taken. The tenant had to replace the ele ments of fertility which he used up. It is clear that the main he buys from the landlord is what we have called the usance of land; but as he usually takes something more (through failure to repair and because of inevitable deprecia tion) he pays for this an additional price included in the gross rent.
§ 4. The medieval rent-charge as a sale of income. It thus came about that land, tho not as an economic good inde structible, was nevertheless in many cases so managed as to yield a continuing income. In medieval times this income or rent was realized in products and services, not in money.
The fruits of the soil were consumed on the spot instead of being sold as now. Land was thought of as a place on which the tenant could live and from which the landlord could draw an income. The medieval estates were so tied up by legal conditions that they could not be sold outright, so means were found of doing practically the same thing. The owner, in some cases, mortgaged the annual rental by selling a rent charge upon it. A rent-charge was an annual sum payable (in perpetuity or until redeemed) out of the yield of an estate. Thus, in the Middle Ages, not the land itself, the mill, the mar ket rights, the forest, etc., were subject to trade, sale, and contract, but merely the usufruct, as a whole or in part, for a definite period. The sale of rent-charges has now only a his torical interest, as loans now are made in other ways, the land being pledged as security for repayment. After this brief survey of the old land tenures we turn now to the modern method of selling the use of wealth of various kinds under the form of the renting-contract.
§ 5. Definition of the renting-contract. The renting-con tract is the agreement of a borrower to pay a specified price for the use of a thing and, at the end of a specified period, to restore it in good condition or pay for its repair. In prac tical business it is necessary to have definite agreements to prevent disputes, and whenever a thing is rented there is a contract, either implied by custom or formally made, orally or in writing. The terms are all specified ; the duration, whether for a day or perpetual, or at the pleasure of either party ; the rent, whether cash, share of the produce, definite or contingent on some events ; taxes, insurance, and repairs, what and how much to be done by either borrower or lender. In the case of things other than land, many other details must be specified. Some of these details may be merely implied in a higher gross rent, which covers ordinary wear and tear, or dinary risk of breakage, fire, etc., and ordinary risks of every kind (e.g., rent of piano, of theatrical wardrobe), the bor rower being liable, however, for unusual carelessness in use.
The form of the renting-contract is observed by men in estimating the uses of their own wealth where no contract exists. If they count the gross product of an agent as a net usance, it is bad bookkeeping. In many cases it is necessary, therefore, for owners to observe the form of the renting con tract in order to determine the net yield of durable goods.