Page:Popular Science Monthly Volume 28.djvu/877

Rh  gravel deposit at West Philadelphia, which Mr. C. E. Hall has regarded as a glacial moraine, "is identical with that which occurs all along the Delaware from Trenton to Wilmington." Even at the Wind Gap, only a short distance south of his moraine line, Mr. Lewis did not see a single scratched or transported [sic]bowlder, nor any striæ or other signs of glaciation, although these were abundant three miles away, where they suddenly stopped.

Bacteria and Surgical Lesions.—The positive demonstration of the important factorage of bacterial growths in surgical lesions, says Dr. H. O. Marcy, of Boston, in an address before a section of the American Medical Association, would seem no longer wanting. Its recognition in the evolution of the systems of modern wound-treatment is apparent, yet Dr. Marcy is ready to admit that "many questions of great magnitude remain unsettled, that many subjects connected therewith are shrouded in doubt and obscurity, and that many fields of great promise remain yet for exploration. Willie this may temper our zeal, and cause us to examine with double caution our premises and conclusions, it can not the less stimulate every thoughtful student to better endeavor and renewed effort." The too commonly held ideas of antiseptic surgery, as consisting of carbolic acid applied as spray, or in dressing, are believed to be "not only superficial and misleading, but distinctly incorrect and injurious." Such imperfect knowledge of any scientific truths must have its fruitage only in evil, leading to a distrust in methods, at the best only half understood, and the results obtained, where protection in wounds has not been secured, are falsely reported in proof that antiseptic surgery is only the fashion of the hour."

Depth of Frozen Arctic Soil.—General Sir J. H. Lefroy communicated to the British Association at its last meeting the results, so far, of researches to ascertain the depth of the permanently frozen soil in the Arctic regions of Siberia and British North America. The depth of the "perpetual ground-ice," as it is called, has been found to be, near Yakutsk, Siberia, three hundred and eighty-two feet. But few actual measurements have been recorded in North America, for the people who possess a perpetually frozen soil do not like to speak of it, for fear that it may be regarded as a stigma against their climate. The greatest thickness of "ground-ice" yet actually measured in America is forty-five feet, as measured by Sir John Richardson in latitude 64° 20' and longitude 124° 15' west. There is good reason to believe, however, that within the Arctic Circle in America a thickness of ground-ice is attained much exceeding that at Yakutsk. Lieutenant P. H. Ray, U. S. A., sank a pit near Point Barrow, in 1883, to a depth of thirty-eight feet. At twenty-eight feet from the surface the temperature of the soil was 12° Fahr.; and it was the same at thirty-eight feet. Taking the unit of increase of temperature per unit of depth under-ground as 1° Fahr. for sixty-four feet, Lieutenant Ray provisionally computed the total thickness of the ice at about thirteen hundred feet. The depth to which the summer thaw reaches and its rate of progress are more variable, for they are more dependent on the season and the exposure than the depth of the frozen soil. They must greatly influence the agricultural capabilities of the place. In some respects the existence of a frozen stratum underground may be regarded as rather an advantage than otherwise The cooling of the surface soil which it effects appears to be a provision to counteract the intense heating power of the sun in the summer months, and to secure a supply of moisture to the roots of cereals when they most require it; so much so that General Lefroy believes that agricultural experience in the Northwest would be in favor of retaining it, even if it were possible to get rid of it.

The Travels of a Storm.—At the meeting of the Royal Meteorological Society held November 18th, Mr. Henry Harries read a paper on "The Typhoon origin of the Weather over the British Isles during the Second Half of October, 1885," which embodied the first daily tracing which has been made of a storm from the Pacific Ocean to Europe. The author showed by means of daily charts that a typhoon which originated near the Philippine Islands on September