cell theory used to be difficult. There may be an excuse for a word picture conveying a vague or possibly erroneous impression, but a pen cut should show what it purports to show. There is no excuse for substituting imaginary pictures for photographs or drawings made directly from the microscope, for cuts that are true to life may easily be obtained.

THE THEORY OF OXIDATION

Another elementary idea that should enter into all physiology teaching is the theory of oxidation. The elementary teacher need not fear to substitute the familiar word "burning" for the longer word, because the more familiar term is often found in the writings of the most advanced thinkers. Oxidation in the body is literally a slow burning, and if it is called burning the children will have no difficulty in understanding its nature.

While the cell theory furnishes the anatomical basis for biology, oxidation is the physiological key which reveals the secrets of many of the processes of the body, especially those which are concerned in nutrition and excretion. The modern science of nutrition is founded on the amount of heat which a given quantity of burning will furnish. Respiration and temperature are details of burning, and excretion is the disposal of the burned products. All muscular action is dependent on burning, while nervous impulses are profoundly affected by it. Over half of physiology is directly and vitally concerned in oxidation. To errors of oxidation physicians now ascribe a large part of the aches and pains, skin troubles, and nervous affections which they are called to treat. Oxidation is, therefore, a topic that should not be dismissed with a lesson or two on the lungs, but should be taught in connection with each organ to every pupil who studies physiology.

THE APPETITES

An animal knows nothing of hygiene, and yet it maintains itself in perfect health by the exercise of its innate appetites and feelings. Thus, its hunger is co-ordinated with its sense of taste, so that in its wild haunts it unerringly chooses its own proper food, and avoids intemperance and excess. Mankind, too, possesses appetites which should be unerring guides in the

proper care of their bodies, and to a great degree of their minds also. The normal appetites are the natural monitors which indicate the way which we should follow in order to keep in health and strength. On the other hand, the perversion of the appetites is the greatest of all causes of sickness, and this fact is the foundation of the whole teaching of temperance. Our eating and drinking may safely be left to our own feelings and appetites, provided only that these feelings and appetites are unperverted. This is a common-sense view which every doctor follows in advising his patients. While we should dwell on perversion of the appetites, yet we should dwell still more on their normal use. Above all, teachers should avoid extravagant or foolish advice, when a reference to the dictates of the feelings is all that is required. For instance, some persons should not read while lying down, but indiscriminate advice not to read in bed is unnecessary. If reading in bed is doing harm the eyes will ache, and that is all there is to it.

The practical application of the details of ventilation, heating and lighting largely come under the head of the feelings. We judge of the purity of the air by the sense of smell, and of the proper degree of heat by feelings, and we can safely trust these senses. Lighting is also largely a matter of eye feeling. But in such topics as these every day should see a number of demonstrations of heater pipes and windows in the adjustments which are needed in each schoolroom. Those teachers who are unfortunate enough to have crowded, dimly lighted and stuffy schoolrooms may yet take consolation in the thought that their room compels them to make daily demonstrations in ventilation, heat and lighting, which, in perfectly equipped buildings, are performed by the janitor out of sight of the class.

INFECTIONS

Next to perversions of the appetite the most common cause of sickness is bacterial infection. Probably nine tenths of the ills of mankind come from these two causes. It is high time that the true manner of taking cold were taught in every school. Sitting in the draft and getting the feet wet are but the minor half of the cause of colds, and the greater half is due solely to

the invasion of bacteria which come from some one else that has a cold.

There are numberless kinds of colds varying from a running sore to a deadly pneumonia, but they all have the common cause of being caught from some previous case. In this fact of infection lies the chief medical argument for ventilation and bathing. To older pupils the work of the white blood cells in destroying bacteria and their poisons should be taught. Few text-books tell the use of the white blood cells, and yet medically they are of the utmost importance. Their uses and their method of action are well known, and their extreme practical importance in constantly guarding us from taking cold should lead every teacher to spend a considerable time on their functions.

Teachers complain that instructors in special branches often lay undue stress on the importance of their own branches, and monopolize an unfair amount of time in them. It is impossible to cover every side of physiology and hygiene, and therefore the foregoing suggestions are about all that the average teacher can utilize. The near future will undoubtedly see these and still more advanced ideas conscientiously carried out as a part of everyday instruction.

O

JOHN T. PRINCE, STATE BOARD OF EDUCATION, BOSTON

IFFICULTIES of a serious nature are found to exist in making a course of studies under present conditions. Over and over again we hear the criticism that the schools teach nothing thoroughly, and as frequently we hear the defence from school authorities that there is no time to do more. It is plain to see how the difficulty has arisen. Fifty years ago but four or five subjects were taught in the schools, and there were six hours a day to teach them in, with an extra half day on Saturday. Later the half day session on Saturday was given up, and the time of the afternoon session was reduced to two hours. Then came the giving up of recesses, and an earlier closing in consequence. In the meantime the number of subjects doubled and trebled, but the length of session remained as before, even with the restoration of recesses. Thus it is that in many places all the exercises of the school, including physical exercises and recesses, are crowded into daily sessions which occupy only four and three quarters hours of time. Even this time is shortened in some places by having only a forenoon session, leaving the afternoon free for home study and recreation. Under such circumstances it is no wonder that it is found difficult to make a place in the program for industrial training, which is now demanding admittance into the school, and which from the nature of the subject must inevitably consume much time.

I can see no way out of the difficulty except by considerably lengthening the school sessions. If exercises in manual or industrial training are to be given daily, as many wise educators advocate, and if more time is to be given to the plays and games of children, the school day should be increased to six hours. That this time is not unreasonable, and that it can be easily brought about with the hearty approval of parents and pupils, is shown by the experience of one of our own normal practice schools. When from experience the desirability of

having industrial work in all grades became manifest to all concerned, the plan of prolonging the daily sessions one hour was proposed, and with practical unanimity it was cordially approved by the patrons of the school. At first attendance upon the industrial exercises was optional, but as a matter of fact nearly every pupil chose to attend, until now both the extended time and enlarged program are accepted by all without question. In some such way as this the introduction into the course of new and desirable subjects of study may be made. Several inquiries have come to me recently as to standards of time for each study of the school. In a special report upon a course of studies a few years ago, I made a careful study of conditions and practices in various sections of this and other countries, and as a result I suggested certain approximate percentages of time to be given to each of five groups of studies. The following table is a revision of the percentages given in that report, due allowance being made for the introduction of industrial training.

TABLE.-Showing the Approximate Percentage, in a Proposed Course of Studies, of the Entire Recitation Time of a Pupil or Group of Pupils spent in I-Language (including Reading, Writing, Spelling, Composition, English Grammar and Literature and a Foreign Language); II—Mathematics (including Arithmetic, Algebra, Geometry and Bookkeeping); III-Elementary Science (including Nature Study, Physiology, Hygiene and Geography); IV-History (including Civil Government, Biography and History proper); V-Miscellaneous Exercises (including Singing, Drawing and Manual Training).

GROUPS

OF STUDIES.

Sub- Grade Grade Grade Grade Grade Grade Grade primary 1

5

Grade

*Including opening exercises, physical exercises, games, singing, drawing and constructive

work.