Page:Popular Science Monthly Volume 42.djvu/443

Rh go to sleep by reading the order to do so; the orders would retain their power when he had not seen the patients for weeks; in fact, he had been repeatedly called upon to give them new pieces of paper when the original talisman had worn out. A captain's wife, in the habit of taking sea voyages and being sick, was now regularly relieved by the author's suggestion.

Useful Bacteria.—It is true, says Dr. H. W. Conn, in a paper on Some Uses of Bacteria, that bacteria are occasionally injurious to us, but it is equally true that they are of direct benefit to us; particularly useful are many of them to the farmer. There are the yeasts, for instance—not bacteria, but microscopic plants closely related to them—the fermenting agents by the aid of which we make bread, wine, and beer. Cider having been fermented by yeast into an alcoholic liquid—hard cider—is further changed in time by the agency of bacteria into vinegar. These bacteria grow on the surface of the hard cider, forming a sort of scum which is the "mother" of vinegar. In the ensilage management of silos, the whole process of procuring proper and sweet ensilage is one of properly managing bacteria growth. During the ripening of cream and the development of the aroma that gives its flavor to butter, bacteria are growing within it "with absolutely inconceivable rapidity" to produce the precious changes. But, "if the butter-maker owes something to bacteria, the cheese-maker owes everything to them. The butter-maker can not get the proper aroma without the agency of bacteria, but the cheese-maker can not get anything. By them unpalatable fresh cheese is converted into ripened, strong, pungent, well-flavored cheese. The quality of the cheese depends on the kind of bacteria that are planted in it, and the selection of these bacteria or the method of introducing them constitutes one of the arts of cheese-making, in which much is yet to be learned; and there is another art in keeping out the noxious bacterium, tyrotoxicon, which poisons the cheese. Bacteria are the powerful agents through which dead animal and vegetable matter is removed by decay. Bacteria also have an important agency in plant life, by promoting the decomposition of compounds from which plants are fed. Of special importance is one particular kind of organism known as "the nitrifying organism," which produces nitric acid. But this is not the end of the agency of bacteria in plant life. They are not only of value in ripening your fertilizers and in keeping up this constant growth of Nature, but we have learned. . . that at the very foundation the growth of plants is absolutely dependent upon these organisms, and similarly in the future the continuance of the vegetable world must be also dependent upon them."

Prehistoric Fish Weirs.—The stone implements, potsherds, and other objects found by Dr. H. T. Cresson in the mud near the mouth of Naaman's Creek, Claymont, Delaware, form the subject of a special paper in the records of the Peabody Museum. The objects were found in close association with the decayed remains of stakes or piles, indicating an aboriginal structure of an unknown character. This structure (or structures) Dr. Cresson conjectures to have been originally fish weirs. Herein he agrees with Prof. H. W. Haynes, who deems it safe to consider them fish weirs rather than the remains of a pile-dwelling people. This confirms the words of the fisherman who first brought the stone implements to notice, when he suggested that "the Indians in old times used to hitch their canoes to them and spear fish, and that was the reason why their darts, axes, etc., were found there." Fish weirs have been mentioned by certain early explorers on this continent, and remains resembling such structures have been referred to by more modern writers.

The Ribs of the Gorilla and of Man.—Describing the articular processes of the gorilla as compared with those of man, Prof. Struthers said, in the British Association, that in the gorilla the chest was planted a vertebra lower than in man. The seventh presented all the characters of the normal sixth, the eighth all the characters of the seventh. In man he had seen the whole chest a vertebra too high. He had met with three cases of a rib more than usual. It was common enough in the human body; instead of the ordinary twelve you had one more at the neck much more commonly than below. In the cases of three out of fourteen gorillas the