Page:Popular Science Monthly Volume 43.djvu/402

 impregnated them with the idea that respect for his companion was for the man one of the prime conditions of moral life. This moral life is her own work. She created and she maintains it. In the cult of which she is the object, in the homage which man renders to her, there is more than the mysterious attraction which sex inspires: there is the instinctive recognition of a great and salutary influence nobly exercised.—Selected and translated for The Popular Science Monthly from the author's article in the Revue des Deux Mondes.



HERE is no physical science without exactness, and there is no exactness without measurement. Far as we are still from understanding the mystery of life, it is not to be denied that the greatest advances in biology have been due to exactness in observation and quantitative comparison. This is more markedly the case with the sciences of geology and astronomy. Still more is this to be insisted on in the study of the forces of inanimate Nature. I have always, for instance, tried to persuade those of my friends who are engaged in teaching chemistry that they would do well to begin at once with quantitative methods and determinations in the laboratory, synthetic as well as analytic.

This quantitative element is still more essential in physics. There everything should be quantitative and exact. But there are different degrees of exactness. No one would expect from the average student of chemistry that all his analyses should be of the same degree of refinement as though he were determining the atomic weight of an element. Let his analyses be sufficiently exact to convince him of the faithfulness of Nature and the trustworthiness of the statements of the science.

Now, in bringing before you to-night a short account of the system of teaching practical or laboratory physics which has been adopted at the Government Science Schools with which I am connected, I must speak a few words as to the origin of that system.

The problem was briefly this. Given a class of students of various ages, from sixteen to sixty, and of various degrees of general knowledge and ability. Assume that they are all anxious to learn, and that none of them have worked systematically before in a physical laboratory, and let the instruction be limited to a few months—say four.

The problem is to give them a sound but necessarily elementary training in the science, so that all shall have an opportunity of acquiring such a knowledge of physics as no educated man should 