These and similar variations are differences not so much of interest as of security, cost of negotiation, and mental attitude. The farm mortgage pays a higher rate than the government bond partly because it is less secure, partly because it involves greater trouble of investment, and partly because it does not run for so long a time. For the same reasons a higher rate of interest is charged on a promissory note than on a bank deposit certificate. Again, the lower rates on government bonds and bank deposits are due in some degree to the peculiar attitude of that class of investors whose savings are small in amount, who are not well aware of the range of investment opportunities, and to whom security and convenience are exceptionally important considerations. If such persons did not exist the rates on government bonds and savings deposits would be higher than they actually are. The higher rates in a new country on, say, farm mortgages are likewise due in part to psychical peculiarities. Where men are more speculative and more eager to borrow money for industrial purposes, the demand for loans is greater relatively to the supply than in older and more conservative communities. Therefore, the price of the loans, the rate of interest, is higher. In one sense it would seem that the lowest of the rates cited above, namely, that on United States bonds, represents pure interest, and that all the other rates are interest plus something else. Nevertheless, the sums invested in these bonds form but a very small part of the whole amount of money and capital drawing interest, and they come from persons who do not display the average degree either of business ability or of willingness to take risks. Hence it is more convenient and more correct to regard as the standard rate of interest in any community that which is obtained on first class industrial security, such as the bonds of railroads and other stable corporations, and mortgages on real estate. Loans to these enterprises are subject to what may properly be called the average or prevailing industrial risks, are negotiated in average psychical conditions, and embrace by far the greater part of all money drawing interest; consequently the rate that they command may be looked upon as in a very real and practical sense normal. While this conception of the normal rate is in a measure conventional, it accords with popular usage. It is what most men have in mind when they speak of the prevailing rate of interest.