Page:Popular Science Monthly Volume 41.djvu/730

712 Reid, in his Studies of its features (National Geographic Society, publishers), occupies a depression in the mountain about thirty-five miles long and between six and ten miles wide. It is fed by a great number of tributaries, the largest of which are again made up of many smaller glaciers. A total area of about eight hundred square miles is drained by the system, and the actual surface of the ice is about three hundred and fifty square miles. The area draining into Muir Inlet is about seven hundred square miles. Most of the precipitation which falls on this area flows off as water in the sub-glacial streams; the rest, compressed into ice, is forced through the narrow gateway two miles and a half wide into the inlet, where the glacier terminates in a vertical wall of ice varying from one hundred and thirty to two hundred and ten feet above the water surface, whence large masses are continually separating to become icebergs. The water is in places seven hundred and twenty feet deep, and, as this is not enough to float a mass of ice rising so high above the water as the glacier, the ice must reach to the very bottom and must attain a thickness of nine hundred feet. The actual length of the ice-front facing the water is nine thousand two hundred feet, or a mile and three quarters. On each side the glacier sends forward a wing, which rises in the shape of a wedge over the stratified sands and gravels of the shore. The wings are fringed by treacherous quicksands, which support large stones and look firm; but the tourist who steps on them carelessly will sink in over his ankles. The ice-front has a wonderful coloring. Places from which ice has recently broken off are deep blue, sometimes almost black. This color lightens under exposure to the air and sun, and in a few days becomes pure white. All shades of blue, in striking variety, are represented in the ice-front.

The Action of Fungicides.—The principle involved in the use of fungicides for plant rusts, according to Prof. Byron D. Halsted, in the Report of the New Jersey Agricultural Experiment Station, consists in the application to the susceptible plant of a fine spray containing the substance that, when in contact with the spores, will either kill them or prevent their development. The whole practice of using fungicides depends upon the fact that these mildews, rusts, blights, and other fungous decays produce minute spores, which are easily disseminated and thereby propagate the trouble far and wide. These spores, either as such or when undergoing germination, are easily injured by various chemicals, notably the compounds of copper. It therefore follows that if these fungicides be placed upon the foliage in a thin film, it will go far toward destroying the spores already there and prevent those subsequently falling upon it from germinating. The ways in which this principle is carried out are many, depending upon the nature of the infected plant. The progress made during the last ten years in the study of fungous diseases is unparalleled. A few workers began collecting and describing some fifty years ago. This was followed a quarter of a century later by a critical study of the injurious species. The first systematic tests of fungicides do not date back more than a decade ago, and since that time, through the Department of Agriculture, experiments were begun which have been continued with well-defined practical results. By means of the experiment stations a new impetus was given to the subject about three years ago, and to-day there is a well-organized crusade against the fungous enemies of crops. The nature of the several blights, molds, and rots has been studied out in the laboratory, while fungicides in large numbers have been tested in the field. The result has been that several of the worst are practically subdued, provided the methods of warfare are followed.

Shuswap Traits.—Among the customs of the Shuswap people of British Columbia recorded by Mr. George M. Dawson is one from primitive times, by which, in the case of a man dying and leaving behind him a widow or widows, his brother next in seniority took the widow to wife. The right of a man to the widow of his deceased brother was considered as incontestable as that to his own wife or wives, and the women had equally a claim to receive from him the duty of a husband. The proper name of a man was changed from time to time during his life, when he would assume the name of some kinsman. Young men on reaching manhood were accustomed to separate themselves and