How often has the question been asked by persons seeking a profitable investment of their capital, Will such a canal or railroad pay? This is really an indefinite question, and admits of no one answer applicable to all cases. It may, for example, in some particular instance, be tolerably certain that at the end of the first four years, if the shares are sold, and the account closed, there will be an entire loss of half the principal, and all interest during that time. If the shares are not sold until the end of eight years, they will produce a return of the original capital, together with a profit of five per cent. If, however, those shares were retained until the end of twelve years, they might, when sold, produce a return of the original capital, together with a profit of ten per cent. during the whole time. Now, it is obvious that the answer to the question, “Will that canal or railway pay?” must depend on the capital possessed by the purchaser and on the period of time during which he can afford to abstain from its use. The purchaser who could not abstain from the use of the interest of his money for four years might be ruined, whilst he who could abstain for twelve, might be greatly enriched. But a wealthy country is generally better able to abstain than any commercial firm, and the investment in discoveries becoming productive at a distant time, will be of far more advantage to a nation than to individuals. A certain number of persons maintain the opinion, that if men of science became rich they would become idle, and that it is expedient to starve them into discovery. Such persons may perhaps have been misled by arguing from a supposed analogy with some other profession. But the pleasure of science arises from the exertion, not from the inactivity of the mind. Others, and a very large number, hold that science is of so sublime a nature, that it ought to be above all sublunary rewards;—they maintain that it is beneath its dignity to wish for the wealth or the honours awarded to success in other pursuits;—that ribbons and titles are quite unworthy of the ambition of those who are searching into the truths of nature. When men state a principle, the best test of their sincerity is to be found in their application of it. We may ourselves utterly repudiate a principle, and yet be unable to show that it is not sincerely believed by those who assert its authority. Man cannot dive into the mind of his fellow-man, and witness the internal conviction he asserts; but he can always examine the _fairness_ with which he applies that principle. Now, if the lofty dignity of science is such that it is, from its very nature, incompatible with wealth—if decorations and titles are entirely unworthy of its legitimate ambition,—then, as a necessary consequence, all pursuits of a higher order are still more absolutely excluded from such vanities.