Page:Popular Science Monthly Volume 46.djvu/407

  is evidently one of Nature's weapons of defense. In some animals it is developed in a wonderful manner. Wherever it is found it becomes to the animal possessing it a powerful means of defense by rendering it inconspicuous, and in some instances wholly unnoticeable.



HE biographer Carlyle relates that the father of Frederick the Great scandalized the conventionalism of his day by removing all upholstery from the electoral mansion; an object-lesson in personal cleanliness no doubt so little appreciated by his contemporaries that, if the sturdy elector escaped the nickname of "crank," it was because the word had not then been invented, at least in Brandenburg. Even six generations later it may be doubted whether Friedrich Wilhelm's antipathy to germ-haunts has been realized outside a few modernly equipped infirmary wards. To the sanitarist, however, even such merely tentative application is a hopeful one, because he has learned to accept with equanimity the impossibility of any other than a gradual adoption of ideas greatly in advance of the average public sense, and to recognize the fact that even conservatism has its uses: the keel and the ballast which hold the ship to its course and, perchance, prevent a capsize—nay, sometimes even an anchor cast to windward—may be as necessary as the guiding rudder or the propelling sail. He has, therefore, no controversy with the slowness of the change-drift if mainly in the direction of better conformity with hygienic requirements; he even looks forward to a time when factories, dwellings, lecture rooms, stores, and every other kind of edifice, public and private, will be as well ventilated and be made as absolutely fire, vermin, and dust proof as the best hospital wards.

Public indifference to hygienic requirements was significantly