Popular Science Monthly/Volume 20/February 1882/Notes

From Wikisource
Jump to navigation Jump to search

NOTES.

Professor W. J. Beal, of the Michigan Agricultural College, in a lecture on "The New Botany," gives a description of the old method of teaching that science that reads much like a burlesque—but which we know is too sadly accurate, for persons living have not forgotten how they "studied botany" when they were young—and then sketches the new way in a most attractive style. In the latter, we study objects before books; a few short talks are given; the pupil is directed and set to thinking, investigating, and experimenting for himself . . . . Before the first lesson each pupil is furnished or told where to procure some specimen for study. . . . For the first recitation each is to tell what he has discovered. The specimens are not in Bight during the recitation. In learning the lesson, books are not used, for, if they are used, no books will contain a quarter of what the pupil may see for himself." And the professor goes on to describe the particular features of his method in a manner that makes most interesting reading.

The International Committee of the Red Cross (Geneva Convention) has offered prizes for three essays, designed to constitute a series, on "The Art of improvising Means for assisting the Wounded and Sick of Armies." The three essays will relate, respectively, to methods of treatment, means of transportation, and the improvisation of an ambulance or a field-hospital. The consideration of the subjects must be limited to improvisation, and have no reference to fore-prepared means of assistance. The processes suggested should be illustrated by designs when practicable; and the essays should be full, scientific works, not manuals, and should describe expedients that have been tried and tested for practicability. The papers, which may be in English, German, or French, should be sent in before the first day of April, 1883. The awards will be made by an international jury, and will include a prize of five hundred dollars for the best essay on each of the three topics, if worthy, and one hundred dollars to the unsuccessful competitors.

Two views are held regarding the relative age of the copper-bearing traps of Keweenaw Point, Lake Superior, and the Eastern sandstone: one, that the traps and sandstone are of the same age; the other, that the traps are an earlier formation (pre-Palæozoic), and the Eastern sandstone a later one (Palæozoic). Mr. M. E. Wadsworth, having carefully examined the relative position of the two rocks, finds that the Eastern sandstone underlies the trap conformably, "that is, as conformably as a bed can underlie a lava which has flowed over it," and that, therefore, it must be older in order of time, but of the same geological age with the copper-bearing rocks. Hence, the "Keweenawan series," which has been projected upon the theory that the copper-bearing rocks are the older ones, has no foundation. The balance of evidence in regard to the absolute age of the rocks appears to be with the views of Messrs. Whitney and Foster, that they are of the Potsdam age.

Seubert having observed that, in the periodic systems of classification of the metals of Meyer and Mendelejeff, platinum comes before gold, while the received atomic weight, 196·7 to 197·8, puts it after that metal, recently undertook the revision of its atomic weight. Having obtained the pure metal, by Schneider's method, he then, with pure potassium chloride and pure ammonium chloride, prepared the double salts by four methods. The mean value of eight experiments, corrected and reduced to a vacuum, gave 194·34050 as the atomic weight of platinum.

The Peabody Museum of American Archæology and Ethnology has been forced for lack of means to suspend the explorations it had undertaken. Its last report, however, shows that it has done much good work and made many valuable acquisitions. The largest gift received during the year was a collection of Peruvian relics of all kinds, particularly rich in fabrics and garments, received from Dr. W. Sturgis Bigelow, which, added to the other Peruvian collections, makes this department an imposing one. Dr. Flint has brought from Nicaragua many copies of inscriptions on rocks and caves. Mr. Edwin Curtis has procured many thousand specimens, which are recorded in 1,431 entries, from the mounds of Eastern Arkansas. Numerous other hardly less important acquisitions arc noticed. The museum has in press a work by Dr. Abbott, of Trenton, New Jersey, on "Primitive Industry, or Illustrations of the Handiwork in Stone, Bone, and Clay, of the Native Races of the Northern Atlantic Seaboard of America."

Professor Dufour has reported to the Helvetic Society of Natural Sciences an interesting observation of what he considers a new proof of the roundness of the earth, in the deformation of images produced on large surfaces of calm water. It may often be witnessed on the Lake of Geneva, and in the case of ships some miles distant at sea.

Professor M. E. Wadsworth, of Cambridge, Massachusetts, recently expressed the opinion, founded on his observations in the region, that the amygdaloid cavities and veins in the Keweenaw Point district of Lake Superior had been filled, by the action of water percolating through the rocks, with mineral matter derived from the adjacent rock. Professor J. D. Dana traversed his view, holding that all changes in the rocks took place before the rocks lost their original heat, and were brought about by means of the moisture inclosed at the time of the eruption, acting generally in the vaporized state. Professor Wadsworth has reiterated his views, with a statement of his reasons for adhering to them, before the Boston Society of Natural History. He claims respect for them because they are derived from personal knowledge of the facts, while Professor Dana's views depend on the observations of others. The discussion involves the question of the extent to which water can permeate rocks.

Mr. William H. Johnson, B. Sc, has described before the Manchester Literary and Philosophical Society, a series of experiments in the electrical resistance of iron and steel wire, from which he has drawn the conclusion that the amount of that resistance is a measure of the resistance of the iron or steel to tensile strain, and of the amount of combined carbon, sulphur, silicon, and phosphorus it contains.

The course of instruction in natural history of the Academy of Natural Sciences, of Philadelphia, which was begun in the spring of 1881, was resumed for the present winter in the first week in January. Courses of from twenty-five to thirty lectures each will be given, with practical demonstrations in the laboratory, on "Physiography and Invertebrate Paleontology," by Professor Angelo Heilprin, and on "Mineralogy," by Professor Henry Carvill Lewis. Professor Heilprin's lectures embrace general considerations relative to various features of the earth's structure and history, and the geological and geographical distribution of past and present life, with special attention in the latter half to practical paleontological demonstrations and advanced instructions. Practical work, including the methods of distinguishing minerals by their external and chemical characters, and blow-pipe analysis, is a regular feature of Professor Lewis's lectures.

Mr. Frederick Curry, an English botanist, distinguished chiefly for his studies of the fungi, died September 8th, aged sixty-two years. He had been Secretary, and was at the time of his death Vice-President and Treasurer of the Linnæan Society. His valuable collection of fungi is to be presented to the museum at Kew.

Professor J. P. Wickersham having been commissioned by the National Educational Association to inquire into the efficiency of education as a preventive of crime, reports that in the prisons of Pennsylvania, the colleges and high-schools are most insignificantly and the fairly educated classes only moderately represented, while one sixth of the crime of the State is committed by the wholly illiterate, who constitute only one thirtieth part of the population. He further concludes that about one third of the crime is committed by persons practically illiterate, mid that the proportion of criminals among the illiterate is about ten times as great as among those who have been instructed in the elements of a common-school education or beyond.

M. Pasteur has succeeded in communicating rabies by inoculation from the brain of a dog dead with the disease. He has also found that by trephining a healthy dog and placing in contact with its brain cerebral tissue from an infected animal, not only is the disease communicated with certainty, but the incubative period is in every case reduced to a few days.

The Surgeon-General of the United States Army reports that the proportion of cases on the sick list of the army last year was 1,768 per thousand of mean strength among the white troops, and 1,984 per thousand among the colored troops. The average number at one time was 44 per thousand of white, and 45 per thousand of colored troops. About one sixth of the number of white and less than one seventh of the colored sick were cases of wounds, accidents, and injuries. The proportions of deaths to cases treated were 1 to 190 among the whites, and 1 to 97 among the colored troops.

M. Fatio explains the theory of disinfection by sulphurous acid by remarking that the vapors of the acid act in two ways on all organisms that depend on oxygen for life, viz., by asphyxiating them through suppression of that element, and by gradually burning them interiorly, the acid being dissolved in their humors or aqueous parts.

A catalogue of the phenogamous and vascular cryptogamous plants of Indiana, prepared by the editors of the "Botanical Gazette" and Professor C. E. Barnes, names 1,432 species, grouped under 577 genera, and is published, though not absolutely complete, to provoke further additions. The flora of the State is divided into four groups, each marked by the physical aspect of the region in which it is found. The regions may be called the "the river-valleys" "the lake-borders," "the prairies," and "the barrens." The prairie plants are disappearing faster than any others under pressure of cultivation. The splendid forests that originally covered the greater part of the State are rapidly disappearing, and a new race of plants is springing up in their place. New species are continually appearing along the rivers and railroads.

Another prehistoric canoe has been discovered while digging in the old bed of the Rhône, near the bridge of Gardou, France. It is excavated from an oak-log, which has been left with its natural form, except that the ends have been beveled so as to give a sharp form to the prow and stern. Braces were left in hollowing out the vessel, to extend across the inside and strengthen the sides, and five pairs of holes were bored in the side, for oars. The boat is about thirty-eight feet long, three feet wide, and two feet deep, and would probably hold about twelve men. It was considerably decayed, and was somewhat broken in getting it out, but has been deposited in the museum of Lyons in a tolerably sound condition.