Page:Popular Science Monthly Volume 16.djvu/598

 premises at St. Petersburg Place, Bayswater, for three months, and when examined on October 24th the butter was as sound and sweet as when first put in, although during the whole time it had practically been exposed to the air, nothing having been done to exclude the latter from the firkin. Without treatment it would undoubtedly have become wholly putrid in that length of time; nothing, however, could be detected by either smell or taste to indicate that the sample had suffered the slightest deterioration, as it possessed all the qualities of flavor and firmness of butter churned the day before. Experts in different parts of the country were furnished samples, and all pronounced the preservation wonderful; they were of the opinion, however, that the best, newly-made butter has a peculiar aroma that is not quite equaled in the preserved butter, while the latter was considered a little "dead," a defect that is removed by the addition of one per cent, of salt. The cost of the preservative does not exceed one halfpenny per pound of butter; it is worked in directly after churning, and requires no further care or attention, except that, like other butter, it should be kept in a moderately cool place.

Are Bacteria found in Healthy Animals?—In the "Journal of Anatomy and Physiology" for April, 1878, Messrs. Chiene and Ewart asserted that bacteria did not exist in the organs of healthy living animals. In the August number of the "Journal für Praktische Chemie" Messrs. Neucki and Gracosa urge the affirmative side of the question. The chief points of the latter's argument we abstract from a recent copy of "Nature": Dr. Burdon-Sanderson plunged an organ from a newly-killed animal into paraffine heated to 110°, it was allowed to cool and then covered with Venetian turpentine to still further protect it from outside infection. Two days after, the organ was found in a clotted and slightly cooked condition on the outside, but bacteria were present in the center. To this, Messrs. Chiene and Ewart replied that the bacteria-germs fell upon the organ in the interval between its extraction and the moment of plunging it into paraffine. This was accordingly guarded against by an antiseptic method, and three days afterward, when the specimens were examined, no bacteria were discovered. The conclusion, therefore, of Messrs. Chiene and Ewart was that, if the organs were treated antiseptically after death, neither bacteria nor their germs will be found; and hence that no bacteria-germs exist in living healthy organs. Messrs. Neucki and Gracosa, in order to prove the contrary, filled a large glass test-tube with mercury, closed it with a slip of glass, and inverted it in a vessel containing mercury. The vessel was then heated until the tube was one third filled with vapor of mercury. It was then allowed to cool; the quicksilver in the tube again condensed; and when that in the outer jar was heated to 120° it was covered with a five per cent, solution of carbolic acid. A portion of an internal organ from an animal recently killed was brought by means of a pair of tweezers under the mouth of the tube, up which it ascended. The apparatus was kept for several days at a temperature of 40°; and bacteria were subsequently found in the specimen. All experiments of this kind led to the conclusion that bacteria exist in the organs of living healthy animals.

Antiquity of Man.—Professor Boyd Dawkins, in a paper on the antiquity of man, read before the Sheffield meeting of the British Association, said that when he examined the great divisions of the Tertiary period in their relation to the highest forms of life, he was confronted by the following important facts: In the Eocene age there was not a single species of placental mammal. There is not a single well-authenticated case of any mammalian species, now living on the earth, having lived in the Miocene age, although the French archæologists claim that man lived then. In the Pliocene age one or two living species make their appearance. Passing to the Pleistocene or Glacial period, living species are very abundant, extinct species are rare. It is in this period that man appears, over an extended area. He is a mere hunter, not a farmer or possessor of wild animals. The prehistoric period which succeeded the Pleistocene was characterized by the absence of the extinct species of mammalia, with the single exception of the Irish elk. At this