Science is another important field of human effort. Science is the pursuit of pure truth, and the systematizing of it. In such an employment as that, one might reasonably hope to find all things done in honesty and sincerity. Not at all, my ardent and inquiring friends, there is a scientific humbug just as large as any other. We have all heard of the Moon Hoax. Do none of you remember the Hydrarchos Sillimannii, that awful Alabama snake? It was only a little while ago that a grave account appeared in a newspaper of a whole new business of compressing ice. Perpetual motion has been the dream of scientific visionaries, and a pretended but cheating realization of it has been exhibited by scamp after scamp. I understand that one is at this moment being invented over in Jersey City. I have purchased more than one "perpetual motion" myself. Many persons will remember Mr. Paine--"The Great Shot-at" as he was called, from his story that people were constantly trying to kill him--and his water-gas. There have been other water gases too, which were each going to show us how to set the North River on fire, but something or other has always broken down just at the wrong moment. Nobody seems to reflect, when these water gases come up, that if water could really be made to burn, the right conditions would surely have happened at some one of the thousands of city fires, and that the very stuff with which our stout firemen were extinguishing the flames, would have itself caught and exterminated the whole brave wet crowd! Medicine is the means by which we poor feeble creatures try to keep from dying or aching. In a world so full of pain it would seem as if people could not be so foolish, or practitioners so knavish, as to sport with men's and women's and children's lives by their professional humbugs. Yet there are many grave M. D.'s who, if there is nobody to hear, and if they speak their minds, will tell you plainly that the whole practice of medicine is in one sense a humbug. One of its features is certainly a humbug, though so innocent and even useful that it seems difficult to think of any objection to it. This is the practice of giving a _placebo_; that is, a bread pill or a dose of colored water, to keep the patient's mind easy while imagination helps nature to perfect a cure. As for the quacks, patent medicines and universal remedies, I need only mention their names. Prince Hohenlohe, Valentine Greatrakes, John St. John Long, Doctor Graham and his wonderful bed, Mesmer and his tub, Perkins' metallic tractors--these are half a dozen. Modern history knows of hundreds of such.