Page:Popular Science Monthly Volume 29.djvu/293

Rh of ship-building. The tree is necessarily destroyed in the manufacture of camphor, but the law requires a new one' to be planted in the place of every one taken away. The gum is extracted by distillation from the chips, the whole tree being cut up for the purpose, and steamed in a tight vessel or box. The steam, camphor, and oil, the immediate products of the process, are conducted through a bamboo tube to a second tub, and from this to a third, which is divided into an upper and a lower compartment. The partition between the two divisions is perforated with small holes to allow the oil and water to pass to the lower compartment. The upper compartment is supplied with a layer of straw, which catches and holds the camphor in crystals. The camphor is then separated from the straw and packed in wooden tubs containing a picul, or one hundred and thirty-three and one third pounds, each, for the market. The oil is used for illuminating and other purposes. The exports of camphor from Nagasaki in 1882 were valued at $290,000.

Protect the Birds.—The Committee on Protection of Birds of the American Ornithologists' Union has begun the issue of circulars, calling attention to the threatened danger of the destruction of our native birds by the greed of specimen-collectors, milliners, egg-hunters, and Vandal sportsmen. A paper by Mr. J. A. Allen, in the first "Bulletin," gives an estimate of the alarming extent to which this destruction is going on. The conditions of modern life are in themselves furnishing what we might now call natural agencies—that is, spontaneous and of constant operation—which contribute more, perhaps, than all previously operating natural agencies combined to limit the increase, or, perhaps, diminish the numbers, of birds. To these may be added the growth of a passion for hunting birds for various purposes and sometimes under mistaken views, which has become so violent that it is almost a wonder that any birds are left. Collectors appear to be charged with a larger share of responsibility in this matter—than notwithstanding there is vastly too much reckless collecting—they deserve. Mr. Allen calculates that the number of birds killed for their purposes since collecting began does not exceed 500,000; while, to gratify the vanity of the "dead-bird-wearing gender" of the human race, not less than 5,000,000 are sacrificed every year! Mr. George B. Sennett, in a paper in which he tells how the pelicans were exterminated from an island off the coast of Texas in an experiment at making an oil from them which proved to be worthless, says that "if a tithe of the truth were known throughout the country at large concerning the sacrifice of bird-life in the names of 'business,' 'enterprise,' 'food,' 'sport,' and what not, from Maine to Mexico, and from California to Alaska, there would be such a cry of remonstrance as would make the bird-destroyers hang their heads for shame"—that is, if there is any shame left in persons capable of engaging in such business. By far the largest numbers of birds are slaughtered to supply ladies' hats; and it is for the ladies themselves to apply the remedy for the evil, by refusing to wear such barbaric ornaments. Noble women in this and other countries are organizing to put down the iniquitous fashion. The object deserves universal support.

Professor Pickering's Telephone.—In a paper read by him before the American Academy of Arts and Sciences, on his "Early Experiments in telegraphing Sound," Professor Edward C. Pickering showed that in 1870, several years before the telephones now in use were invented, a receiver was devised, constructed, and tried, which consisted of a flexible iron diaphragm, supported at the edges and replacing the armature of an electro-magnet. Musical sounds were telegraphed successfully, and the apparatus was described at a scientific meeting, of which a report was published in the "Troy Press" of August 24, 1870. In 1872 and later, the experiment was repeated under various conditions. In 1879 it was shown that the instrument was capable of serving as a telephone, and of rendering articulate speech audible at a distance. It appeared to differ in no way in principle from the receiver now used. Professor Pickering explains, however, that all his experiments were made, or were intended to be made, with