the pupil to self-activity in a natural manner. Its abuse happens when the subject is presented in a confused manner, or scientific precision is lost by using too familiar language or by too much pouring-in without exercising the pupil by making him do the reciting and explanation. The excellence of the text-book method consists in getting the pupil to work instead of working for him; in teaching him how to study for himself, and to overcome difficulties by himself, instead of solving them for him. Unless the teacher knows this and directs all his efforts to achieve this end, very great abuses creep in. Thus it may happen that the teacher requires the pupil merely to memorize the words of the book, and does not insist upon any clear understanding of it. Indolent teachers lean upon the text-book and neglect to perform their own part of the recitation. But in the hands of the good teacher the text-book is a powerful instrument to secure industry, precision, accuracy, and self-help on the part of the pupil.

NOTES.

THE theories expressed in the "Monthly" by Mr. Eaton and Mr. Gouinlock, that constriction of the blood-vessels of the head by tight hats is a chief cause of baldness, have been reviewed by Professor T. Wesley Mills, who only partly accepts them, and holds that the principal root of the trouble is in nervous strain. Men, by their position and more intense responsibilities, are more liable to this disorder than women, because they are more subject to mental overwork. 66 Baldness," this author concludes, "is one more of the many warnings of our day-one of Nature's protests against the irregular and excessive activity maintained in this restless age."

"THERE is no reasonable doubt," says J. L. Kaine, of Milwaukee, in a paper on the "Condition of Health in Cities," "that if the public would apply such laws as sanitarians are agreed about, there would be an immense gaving in human life and in the time and money now lost through sickness. The conditions of health in cities involve only fresh air and wholesome water. Given these, which a man can not provide for himself, and given the exercise of some control over the character of the food-supply, a man can take care of other conditions himselfhe can keep a clean skin and be temperate and take exercise."

THE Medico-Legal Society of New York offers the Elliott F. Shepard prize of $100 for the best essay on any subject within the domain of medical jurisprudence or forensic medicine, with second and third prizes of $75 and $50, respectively, for the next best essays. The competition is open to all students in the subject throughout the world, bers of the society. It will close on the upon the condition of their becoming mem1st of April, 1888. Papers designed for it should be sent to the president of the society, New York.

MONOTONOUS, Continuous sounds are recommended by various persons as promotive of sleep. Any one who has experienced the murmur of the insect and leaf life of a forest knows how quieting it is. So the purling of the waters, the humming of a hive of bees, the buzz of a spinning-wheel, and the murmur of a distant factory, all act as lullabies. And Mr. S. N. Stewart asserts in the "Scientific American" that there is no better sleep-guard than machinery. A person having a spring or electric or water motor to run her sewing-machine need only remove the needle, place the machine near the patient, and let it run.

THE new work by Dr. Charles Mercier on the "Nervous System and the Mind," which is intended to serve as an introduction to the "Scientific Study of Insanity," will contain an exposition of the new neurology as founded by Herbert Spencer and developed by Hughlings Jackson; an ac

count of the constitution of the mind from the evolutionary stand-point, showing the ways in which it is liable to be disordered; and a statement of the connection between nervous function and mental processes as thus regarded.

A BAND of forgers of Swiss lake-dwelling antiquities have been detected and brought to trial, who appear to have been carrying on a quite extensive business. Among their deceptions was the installation of a spurious "horn age," which they effected by rudely carving objects of horn and be excavated. planting them where they would afterward

DR. ALBERT E. LEEDS, in the American Association, after referring to the rapid pollution which local water-supplies are undergoing in consequence of the growth of manufacturing towns, described what he called the "American System of Water Purification." It comprises three distinct features: Artificial aëration under pressure; precipitation of dirt, sewage, hardening constituents, and coloring-matters, by harmless precipitants; and mechanical filtration through filters capable of rapid reversal of current, with cleansing by mechanical means.

M. HILT, director of the coal-mines of La Wurm, near Aix-la-Chapelle, has devised a way for keeping the galleries clear from fire-damp by establishing a system of piping, through which the gas is sucked away into a reservoir. It can then be prepared and applied to any use for which carbureted hydrogen is suitable.

THE amount expended by the British people on alcohol appears to be diminishing with considerable regularity. The total for 1886 was £122,905,785, against £123,258,906 in 1885, and £146,288,759, the highest expenditure, in 1876. The diminished amount drunk is, however, still enormous, and it is worthy of remark that it is drunk by a diminishing number of persons, for the number who abstain totally, or drink exceedingly little, is steadily increasing.

THE efficiency of oil, when dropped on the water, to calm boisterous waves may now be regarded as established. It is astonishing how small a quantity of oil will answer the purpose. Admiral Cloné gives the amount as from two to three quarts an hour dropped from perforated bags hanging over the sides of the ship in positions varying with the wind. The oil, then, by its own outspreading, extending over the waves, forms a film of less than a two and a half millionth part of an inch in thickness; and this is enough to reduce breaking waves and dangerous "rollers" to unbroken undulations that are practically harmiess. The oils that have been found most effective are

seal, porpoise, and fish oils. Mineral oils, such as are used for illumination, are too light; but the lubricating oils are denser, and may be found sufficient.

MR. J. NORMAN LOCKYER, in his "Chemistry of the Sun," states his theory of dissociation by saying that "chemists regard matter as composed of atoms and molecules. The view now brought forward simply expands this series into a larger number of terms, and suggests that the molecular grouping of a chemical substance may be simplified almost without limit if the temperature be increased."

OBITUARY NOTES.

SIR JULIUS VON HAAST, whose name is closely associated with the record of geographical and geological investigation in New Zealand, died August 16th, in the sixty-eighth year of his age. He was a native of Bonn, Germany, and a student at its university. He was commissioned by an English company to go to New Zealand for the purpose of showing its suitability for German elements; and having arrived there in 1858, devoted the larger part of the rest of his life to scientific exploration. The re

sults of this work are given in his "Geology of the Provinces of Canterbury and Westland," and in many papers in English scientific societies on the geology and physical geography of the islands. He discovered the Grey and Buller coal-fields, and several gold-bearing districts; instituted the Canterbury Museum, the first museum in the southern hemisphere, which has more than one hundred and fifty thousand labeled specimens, and founded the Philosophical Institute of Canterbury.

GUSTAV THEODOR FECHNER, Professor of Experimental Physics at the University of Leipsic, has recently died, in the eighty. seventh year of his age. He was best known by his work on psycho-physics, or the law of relation between the intensity of the stimulus and that of the resulting sensation, which he begun when he was nearly sixty years old, and which has become the center of a considerable literature. He was also active for many years in other branches of science, and was the author of a book of poems and a book of riddles.

of Physics and Director of the Physical PROFESSOR BALFOUR STEWART, Professor Laboratory in Owen's College, Manchester, England, died a few days before Christmas, in the fifty-eighth year of his age. He made his first start in commercial life, but soon turned his attention to science. His first scientific papers were published in the "Transactions" of the Royal Society of Victoria. He studied, experimentally, the radiation and absorption of heat, and for his labors

received the Rumford medal in 1868. As

director, for about ten years, of the Kew Observatory, he established the instruments for the self-registration of the direction and intensity of magnetic force. He was much interested in psychical research. Besides his "Elementary Practical Physics," and other properly scientific publications, he was the author of the curious books, "The Unseen Universe," and "Paradoxical Philosophy."

HERR AUGUST KAPPLER, from whose sketches of Dutch Guiana we have extracted an account of the monkeys of the country, recently died at Stuttgart, aged seventy-one years.

PROFESSOR CHARLES L. BLOXAM, Prodon, died November 28th, in the fifty-sixth fessor of Chemistry in King's College, Lonyear of his age. He was distinguished in technical and analytical chemistry, and as the author of several hand-books of chemistry and metallurgy, and of an excellent textbook of chemistry.

DR. E. BALTZER, Professor of Mathematics in the University of Giessen, died November 7th, in the seventieth year of his age.