3. _The most usual form of short-time loan is that made by a bank or broker to business men on security of commercial paper._ By commercial paper is meant promissory notes given by customers of the merchants, bills of lading for goods that have been shipped to their customers, and various other evidences of indebtedness that may be offered the banks for discount. When goods have been sold on time (as thirty, sixty, or ninety days) the seller has the choice between letting the time expire and collecting the bills direct from the customers, and discounting the bills for ready money at the bank. According to the conditions and needs of the particular business, either method may be chosen. In most industries there is need for larger capital at the seasons when the product is put upon the market. The merchant or manufacturer plans his business in the expectation of an average rate of discount at such times, and if it chances that the discount rates are abnormally high, he has no choice but to go on borrowing and paying the high interest out of the expected profits of his business. This risk of a change in the interest rate is one of many chances he has to run. [Sidenote: Long-time loans by purchase of mortgages, bonds, and stocks] 4. _Most debts in modern times are outstanding for a term of years and represent the lender's purchase of a claim on the earnings of some productive enterprise._ The simplest forms of long-time loans are those made on the security of real estate, which is mortgaged to the lender for the term of the debt. Usually the debtor is obliged to pay the interest either annually or semi-annually, and often, but not always, is permitted to reduce the principal by partial payments. These real-estate mortgages rest on the security of the particular mortgaged wealth, and, unlike most short-time loans in bank, are not personal obligations resting on the general credit of the borrower. Most other long-time debts share this character of being non-personal; if payment is defaulted, only the particular wealth can be sold for payment, not the general wealth of the borrower. Corporation bonds, issued by railroads and other large stock companies, have increased greatly in number in recent years. They yield an income fixed in advance, and are secured usually by mortgage on the entire property of the corporation issuing them. The income of some special kinds of "preferred stocks" is so guaranteed as to make them for investors substantially the same as bonds. Another large class of long-time loans are those made by national, state, and local governments. Tens of billions of dollars of public debts are now outstanding, held by private investors in every walk of life.