Page:Popular Science Monthly Volume 20.djvu/739

Rh of the brain, in consequence, probably, of the increased flow of blood into the veins of the thoracic cavity; the increase of volume in the brain, when it takes place, is, on the contrary, due to a more abundant flow of arterial blood to the encephalus.



to Professor Cope's "Review," members of the order of Rodentia were very abundant during the White River and Truckee (Miocene) epochs in North America. They are referable to thirty-one species and eight genera, of which three genera—Sciurus, Hesperomys, and Lepus—still exist in the regions where their fossil remains are found. All the species belong to the three great divisions of the order which now inhabit North America, while the fourth division, Hystricomorpha, now very sparingly represented on the continent, has not been detected in the formations in question, but appears in a single species of porcupine in the Loup Fork bed. None of the species are of larger size than their modern representatives, while the beavers, squirrels, and rabbits are smaller.

has called attention to a story told in the "Histoire de la Louisiane" by M. Le Page du Pratz, of a Yazoo Indian named Moncatch Apé, who, before the year 1720, made a journey to the upper Missouri, thence over to the head-waters of the Columbia, in regions then wholly unknown to white men. Reaching a tribe of the Pacific coast, he learned that the Indians were visited regularly every year by white men with long, black beards, who came in fleets of thirty pirogues or more. They were described as stout and short, with large heads covered with cloth, their coats coming down to the middle of their legs, which, with their feet, were covered with a red or yellow dress. Their arms made a great noise and a great fire. M. de Quatrefages believes that those visitors may be identified with the Loo-Choo Islanders.

Riley has described a new imported insect which has been found preying upon the clover-fields at Barrington, New York. Its damages were first observed in the latter part of April, when small patches of clover showed the leaves to be badly eaten, and increased till the end of July, when acres of the clover were ruined. The insect continued to lay its eggs till October, a part of them outside the plant, but most of them inside of the old and hollow stems. The insect is a beetle, known as the Phytonomus punctatus.

of Hong-Kong, gives a good account of the success which has attended the faithful practice of vaccination among the Chinese of that colony and the neighboring mainland. No port in the world is more liable to a visitation of small-pox; yet the disease never spreads at Hong-Kong. The health-officer of the colony, noticing that nearly all the young Chinese emigrants had vaccination or inoculation-marks on their arms, learned on inquiry that the doctors of the Tung-wa Hospital—a native charitable institution—practice vaccination upon their countrymen in the colony, and send travelling vaccinators over the adjoining provinces of China, using lymph supplied them by the British Colonial Office.

in a communication to the Boston Society of Natural History, has given his reasons for believing that the iron-ores of the Marquette district, Lake Superior, are of eruptive, and not of sedimentary origin, as has been commonly held. He rests his conclusions upon the fact that the jaspilite and iron-ore in this district, while they offer no characters inconsistent with those which known eruptive rocks have, "possess characters which eruptive rocks exhibit, especially in relation to other rocks, and which no sedimentary rock, proved to be such, has been known to have." The particular facts supporting this view are given in the paper.

has made experiments toward ascertaining whether calomel is liable to decomposition in the human system, with the production of corrosive sublimate. He has found that calomel may be slowly decomposed and corrosive sublimate formed by the action of water at the temperature of the body, and that the change is accelerated by the presence of citric acid, sodium chloride, or sugar.

geological formations of Schuylkill County, Pennsylvania, embrace, according to Mr. P. W. Sheafer's monograph on the subject, the rocks, with an exception or two, from the Oneida conglomerate (Upper Silurian) to the coal-measures. The only formation of importance for its mineral wealth is the last. It rests upon the Pottsville conglomerate (Millstone Grit), which has served as a barrier to protect the coal-deposits from erosion, and which varies in thickness from 675 to 1,030 feet. The coal-bearing strata are 3,000 feet thick at their thickest point, and include, perhaps, thirty coal-beds, of which fifteen are workable and over three feet thick, giving a total of 107 feet of coal. The series can be separated into three divisions by the color of the ash of the coals: a lower or white-ash group, a middle or gray-ash group, and an upper or red-ash group, 