The next important part is the financial side of it. The estimate for this must necessarily vary with the intended mode of disposal of the prospective invention after its perfection.

If it is the intention of the inventor to dispose of his invention after it is perfected, the expense can be approximately estimated, and in many cases will be moderate, of course varying with the nature of the invention. But if it is the intention to manufacture it, create and supply a market for it, the required capital will always be considerable.

For many obvious reasons, it is considered advantageous for the profitable exploitation of an invention to have the financial end of it under a separate head, which is generally the case. Usually this is "making a virtue of necessity," as inventors seldom have anything outside of their "aspirations and prospects," whether it is that "necessity is the mother of invention," or that "Invention is the mother of necessity," is something that physiologists have not quite determined. But in any event, the prospective successful inventor must provide himself with a "finance minister," variously designated as "Angel," "Backer," or "Octopus."

This part of the inventive problem, to many an inventor, is insolvable for many reasons. To solve it successfully requires good insight, and judgment of human nature. Ability to impart one's own "enthusiastic aspirations," and to keep it up, requires diplomacy and tact.

But solve the problem he must if the inventor wants to be successful, and various means have been employed to do so. One of them, which is probably as good as any, is for the enterprising inventor to divide that part of his problem into two or several parts. If he cannot command a large amount at once, he will devote his energies to interesting successively small amounts, which will enable him to carry on the development of his invention from one stage to another; each time advancing it further, becoming stronger, and showing enhanced prospects. To sell to each successive "Backer" the interest of his predecessor, and if the predecessor's money has been used to good advantage, that can be done profitably, and to the satisfaction of everybody concerned, as well as increasing the available means for carrying on the exploitation of the invention.

That is one of the ways by which an inventor can provide himself steadily with some one to take care of the "finance portfolio" in his cabinet.

Another, but far more hazardous way, is to resort to the professional promoter.

Great care, however, must be taken by the inventor in these various financial transactions, which necessarily include the making and signing of various contracts and legal instruments, that his entire invention as well as himself are not entirely absorbed by others.

As competent and reliable legal advice may not always be within his reach, he must be able to make contracts advantageously, and above all to be the possessor of a vision sufficiently penetrating to detect "the nigger in the woodpile," in any paper before he signs it.