THE POPULAR SCIENCE MONTHLY.
being rated at 4,800 and another at 20 quarts a minute. At the averaged rate of supply, each of the wells should furnish water enough to sustain 15,000 palm-trees, representing a plantation of 425 acres. Each tree, if thriving, well manured, and cared for, will bear from one hundred to one hundred and twenty-five pounds of dates; raised by the quantity and without manure or particular attention, the average crop per tree is thirty-five or forty pounds, and this is worth about sixty cents. It is not a matter of very great expense to start a plantation of dates. A lot of five or six hundred acres, on which 30,000 trees may be planted, can be bought for about five hundred dollars; the wells will cost eight hundred dollars apiece; the trees cost about thirty cents apiece; and M. Jus estimates the whole expense of stocking an oasis with 10,000 trees at about $4,000. The trees are expected to bear a crop in the fifth year after planting. The cost might be greater and the time of waiting longer than is calculated, as will often probably turn out to be the case, and the enterprise still be a profitable one, especially as the expense of the outlay, it is thought, may be nearly covered by the barley that may be raised with the aid of the winter rains. The care of the young trees is intrusted to tenant farmers, who take half the barley and a sixth of the dates. When the plantation has come into bearing, it will return, if all is prosperous, 375,000 pounds of dates, worth $6,000 gross, of which the proprietor receives $4,800, or a few hundred dollars more than his estimated first outlay. The prospect has proved flattering enough to attract the attention of a few capitalists who have started several plantations near Ourlana, in the center of the oasis.
The Poisonous Principle of Bulbs.—Professor Husemann remarked several years ago that a certain class of poisons was generally diffused in plants of the families Liliaceæ and Amaryllidceæ. His view has been confirmed by the results of later researches. Gerrard has extracted from the tulip a poison called tulipin, the nitrate of which, according to Sydney Ringer, has the power of stopping the contraction of the heart, with many of the properties of veratrin. Professor Warden, of Calcutta, has extracted from a lily of India a very poisonous principle (superbin), which appears to be identical with the scillitoxin of the squill, and a very small dose of which killed a grown cat. The presence of the poisonous principle in bulbs, on which many plants are more dependent for propagation than on the seed, has an important bearing on the perpetuity of species by its agency in preserving them from the attacks of animals which would be likely to destroy them by eating them. "While the poisons are comparatively harmless to men, they are peculiarly deadly to the rodentia; and it is from the depredations of animals of this class that bulbs would be most likely to suffer.
Scope and Value of Anthropological Studies.—Professor Otis A. Mason, in his address before the Anthropological Section of the American Association, on the "Scope and Value of Anthropological Studies," answers the inquiry as to what benefit the world has derived from the cultivation of that science: First, every study is improved by study, and, if "the proper study of mankind is man," it is eminently important that that should be improved and pursued scientifically. Secondly, the value of a study must be estimated by its effects upon human weal; and are not the questions agitated by anthropologists connected with human welfare? "Do they not relate to the body, mind, and speech of man, to the races of mankind, their arts, amusements, social needs, political organizations, religion, and dispersion over the earth? For instance, the French in Africa, the British in India, and our own citizens in malarious and fever-laden regions, have they not learned from loss of treasure, ruined health, and the shadow of death, that there is a law of nature which can not be transgressed with impunity? It is the same with sociology and religion. The pages of history glow with the narratives of crusades against alleged wrongs, which were in reality campaigns against the sacred laws of nature. Social systems, which had required centuries to crystallize, have been shattered in some effort to bend them to some new order of things. Arts and industries planted in uncongenial soil, at great