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calorie of heat means something after the specific heat of a few substances has been found. Pupils may give with absolute accuracy the definition of a unit without understanding its real meaning. Why does a pupil go into the laboratory after making a fine recitation concerning the insulating properties of cotton and wrap the cotton covered wire around the binding post and expect a flow of current. I have watched this matter for eight years and have seen it happen again and again. Often the best pupils were guilty of this. Of course the mistake was often soon detected and corrected yet it emphasizes the need of direct contact with the things under discussion to get a realizing sense of them.

In disciplinary value quantitative work excels. Keener observation, more cleanliness. greater accuracy in manipulation, better reasoning, and a finer comprehension of the entire experiment is necessary to success. The co-operative method of getting answers common to all departments of work finds little application in closely supervised quantitative work. The classes, however, should be small and all computations should be made in the laboratory.

I have already said that the real limitation of quantitative work is not the fault of the experiments. The teacher is responsible for its shortcomings. I have taught classes in history, mathematics, and different branches of science and I am ready to say that there is no comparison between directing quantitative laboratory work and teaching other subjects. If quantitative work accomplishes what I claim for it, then a generous amount of good hard work must be done by the teacher. I know from personal experience what will happen if the teacher relinquishes even for a short time his hold upon the work. To begin with, the experiments must be carefully selected to illustrate points that have come up for discussion in the class. The apparatus must be tested to see if sufficiently accurate results can be obtained to illustrate the point. Sources of error must be removed or pointed out and then the most careful vigilance given in order to correct blunders, assist in difficulties, suggest modifications, direct the reasoning, and even to help frame conclusions. I would not burden the pupil with percentages of error. Perhaps you are saying, Why not let the teacher do the experiment? It certainly would be easier for the teacher and insure more accurate results, but what is the course designed for, the science or the pupil? We all recognize the fact that it is easier to do a thing ourselves than to teach others to do it. Even if the teacher does do half the work and the thinking, the pupil is better off than if the teacher had done it all, expecting the pupil to follow it and grasp it. It must be remembered that we are using the subject-matter of physics and chemistry as means of education of the pupil. In the hands of a competent teacher, one willing to work hard and long, who knows all the weaknesses of the experiment by personal performance of it, quantitative work will interest, instruct, and inspire.

It has been said that the idea of the grandeur of science has been weakened by too much quantitative work. One likes to revel, it seems, in the utter impossibilities and improbabilities of matters scientific. Great good has been accomplished if quantitative work convinces that something cannot be gotten for nothing, that a vest pocket chemical fire extinguisher is a delusion, and electric finger rings a fake. Who it is that makes all the wild statements as to what will be accomplished by electricity in a few years, how its application will be extended indefinitely and its price reduced to mere nothing? Surely not one investigating its laws. A quantitative study of Ohm's law and associated laws might take the poetry out of such dreams.

Quantitative experiments are doing a good work and will do more as teachers learn to use them. Too much has been undertaken both in extent and complexity. Too much attention is given every year to devising methods of making quantitative experiments out of everything. Heaven knows we have enough now. I believe in progress but I also believe that the average boy or girl in high school has something else to do in addition to his physics and chemistry.

DISCUSSION

W. A. FISKE, instructor in physical science, high school, Richmond, Ind.-It has always been interesting to me, as no doubt it has to others, to watch the growth and development of scientific work. Pick up a textbook in physics fifty years old and you certainly find a book of great interest. It contains not a trace of the word laboratory, not even a quantitative thought. These things were left for later days.

When we consider physics from a laboratory standpoint we find that three stages or periods have existed: first, the period of no laboratory; second, the period when there was a tendency to all laboratory; and third, a more conservative period, or that of a middle ground, a return to more class and lecture work. When we think of this unsettled condition of affairs there comes to our mind an expression of Goethe. A friend once said to him, "Why do you care so much for Homer when you cannot understand him anyhow ?" To which this great German replied:

Neither do I understand the sun, moon, or stars, but as I look upon these mysterious orbs as they pass over me day by day, and as I ponder their wondrous ways, I think at the same time: When shall I ever be of any importance, and when shall I know the real truth of things.

That is the main object we have in so often discussing these questions, to find a little truth to which we may anchor our hopes and build for the future.

The purpose of laboratory work is not that of discovery, or not verifications in itself, but as the writer of the paper has said, to bring the pupil to a realizing sense of things; to cause him to know, to think, and to do things that he may find out more.

Quantitative laboratory work possesses a dignified nature. Such experiments give the student the impression that he is doing something, and not that he is merely engaged in play.

This kind of laboratory work may have a bad application, if the experiment is made the end in itself. All experiments should be worked in connection with the laws and principles which they illustrate and should not be delayed until the end of the subject in hand. The number of experiments should be few, as simple as possible, and easily within the grasp of the pupil.

The value of such experiments to the pupil cannot be overestimated. patience, accuracy, cleanliness, skill, and careful and systematic thought. It has been said by a writer in a recent scientific journal,

They teach care,

If a student is able to handle correctly a spherometer or vernier caliper, if he is able to measure the focal lengths of a lens without dropping it on the floor, or if he can handle any piece of apparatus, successfully, wipe it off, and lay it away as he found it, he has made an acquisition for life.

Finally, this kind of work, as has been suggested by the author of the paper, while being alone in the laboratory must have the constant care and attention of the teacher in order to make it of the greatest value to the pupil

CARL I. INGERSON, instructor in physics, Central High School, St. Louis, Mo.Students seek the line of least resistance and find it in qualitative experiments. We have been kindergartenizing education. College presidents report entering students more poorly prepared than ten years ago. High-school principals report the same with regard to those coming from the grades. We can help to make the students better thinkers by

plenty of strong quantitative work.

J. FRANKLIN WALKER, principal of high school, Anaheim, Cal.—On the contrary, work is much better done in the high schools today than it was ten years ago.

C. M. WESTCOTT, Redlands, Cal. I believe a certain amount of qualitative experiment should have a place. Any supposed weakness of the schools of today compared with those of ten years ago cannot be due to the introduction of qualitative work, since there is today more and better quantitative work than there was then.

A. B. MARTIN, principal of high school, Marysville, Cal.-We have used the plan of giving one day to recitation on a given subject, then two days to laboratory work on the same subject, followed by two days of recitation on the same subject.

The request was made at this point that the opinion of the section be obtained as to the relative amounts of quantitative and qualitative experiment desirable. A vote was unanimous that in physics quantitative experiment should exceed 50 per cent. and onehalf present thought it should exceed 75 per cent. In the study of chemistry it was voted almost unanimously that quantitative experiment should not exceed 10 to 25 per cent.

LEWIS B. AVERY, principal of high school, Redlands, Cal.-Qualitative work in science gives a philosophical view-point and is generally cultural in effect. Quantitative work is purely scientific. I am of the opinion that a general view of any science should precede its minute scientific study. In the Redlands High School we give a half-year preliminary cultural course in physics which is as nearly compulsory as may be, and follow this by an elective year with strong quantitative work. This preliminary half-year is conducted without textbook and is in the form of illustrated lectures and experimental answers to pupil's questions. The requirement for entrance to the room each day is the prepared notes on the preceding day's work. After a three-years' trial we are fully convinced of the value of this general course for those pupils who get no more physics and for those who take the quantitative work as well. The latter class know what they are doing and where they are going: they see the trend of the work that they do and its general bearing upon the whole subject.

THE USE OF THE MICROSCOPE IN BIOLOGY CLASSES

I. PURPOSE OF WORK WITH THE MICROSCOPE

WALTER M. KERN, PRESIDENT STATE NORMAL AND INDUSTRIAL SCHOOL, ELLENDALE, N. DAK.

Much is being said and written these days about the "new education." Somebody seems suddenly to have discovered, what most of us are inclined to believe people always knew, that the child is dual by nature; that he possesses receptive and expressive faculties; that they are intimately related, "useless each without the other;" that impression must precede expression, and that the highest type of training is that in which both receptive and expressive faculties are jointly trained. The boy who works at the lathe, who turns from wood a cylindrical form, has fashioned his conception in the concrete. The finished product represents impression transformed into expression, and the mental training acquired in mastering the tool, in manipulating the power, instruments, and material, represents that type of education in some quarters denominated the "new." So with the microscope. These two instruments have at least one point in common; they open up a new world to the experimenter. They are the agents thru which his untried powers seek to try, to investigate, to know; by which the mind, thru the medium of hand and eye, acts and reacts upon the unknown and untried; and the proper use of either may well represent that type of training in which the student's powers of initiative are developed in gaining knowledge at first hand, while their use indicates that we have gone back to Locke and Pestalozzi in our attempt to put in practice our educational ideal.

The microscope in secondary-school courses has played a various and diverse part. We have had three types of science-teachers in secondary schools. The first of these belonged to the "old school." He was the teacher whose receptive faculties had been highly trained. He knew his sums and he knew his texts. He believed all the wonderful things that some compiler had written about nature. He knew the names, the pictures, and the derivation of much of the nomenclature of the flora and fauna described. He knew a few of the forms that greeted him afield. He had unbounded faith in his text. He would believe it rather than the evidences of his own senses. It contained an excellent résumé of what someone sometime, somewhere, thought about the things to which it

pertained. It related in but a very minor degree to field and pond-to that nature with which the universe is alive. The teaching lacked the vital element; there was none of that eager impulse that follows personal contact; and the students went thru life believing that off somewhere in earth or sea or sky are more wonderful things than most men have dreamed about. Of their own parish they were unfortunately ignorant. And this was the old school which some of us have occasion to remember; happily passing into the great beyond.

And the second type is the opposite extreme; the university graduate who has been trained in microtechnique and who is possessed with the idea that high-school pupils must of necessity be interested in whatever interests their teacher. There is a pond near at hand, but material for class use is purchased from a marine supply-house because such a proceeding lends an air of dignity and superiority to the transaction. The course is planned to lead to the mastery of the microscope; the study of cell, chromatophores, crystal, rudimentary tissue, soft tissue, thick-angled tissue, stony tissue, milk tissue, sieve tissue, tracheary tissue, groups of tissue, etc., exact measurements and drawings. Of the local flora and fauna; their life history, adaptation, and classification the student knows almost nothing. He does know much about the use of the microscope and microtome and is able to use these instruments to some advantage. Such teaching is the result of an impatient zeal on the part of an over ambitious teacher. The students have certain advantages. Their markings are accepted without question, but one is prone to feel, after all, that there is something foreign and irrelevant for the majority of the student body.

Happily we have come to that state where, if our heads must be in the clouds, we realize that we must keep our feet on terra firma. The third type of teacher attempts what Cicero denominates the "golden mean." The archaic teacher, intent on the text, makes no use whatever of the microscope. The budding specialist makes it his vade mecum, the cardinal point about which all knowledge revolves, the be-all and end-all of the secondary course in biology. It was to be expected that we would swing from one extreme to the other, but since the balance has ceased to vibrate it is easy to approximate the correct position of this instrument. Field work has a most fundamental place in the study of biology. Beginning with a clear distinction between organic and inorganic, it is the adamant upon which future comprehensive training must be built. The work of the student in the secondary school must, of necessity, be introductory. He must be taught a method of work; must know how to study; must appreciate the value and utility of materials. He must know the local field and work thru it. He must know something of distribution and its causes; must know adaptation; must have such a training in types as will enable him readily to arrive at an approximately correct determination of a form's systematic position among the orders. He must know something of the relationship existing between plants and animals and between the different groups of each respectively; must be able to reason from structure to function; must know morphology and physiology, and whatever purpose the microscope may serve in such a course will constitute its legitimate field. The extent to which it is used must depend in a large degree upon the locality and the view-point of the individual instructor. If material is abundant, and if the instructor believe that emphasis should be laid upon some special branch whose representatives are prevalent, such as the arthropods or phenogams, the work with the microscope may be limited to the study of slides representing gross structure. Such a course may well proceed from the study of individuals through family, order, class, and branch to the conception of a kingdom and embrace a systematic and logical body of knowledge. Or an equally logical and more extended course may embrace a knowledge of the leading characteristics of the chief branches of animals and plants, and thruout the course the microscope may be a daily necessity to the working student. Such courses are logical; their pedagogical content intensive; and in either the microscope has reached a sphere of usefulness that is at once proper and legitimate.

Primarily, and aside from the discussion of prevailing methods and the proper position

of the microscope there are at least four major fields which embrace the proper use of this instrument.

I. It introduces the student to a new world.-There is a world beyond the range of the unaided senses and into it the microscope ushers the student. It has been well said that the purpose of education is always the same but that the means vary according to our conceptions of life. The microscope is one of the means to an end. Thru the avenue of the eye we acquire most of our information concerning the things about us. Try as we may, all our senses are limited, the perfectly-developed eye being no exception. The microscope supplements artificially the eye. It illustrates how man takes up and carries forward nature's work. All of our native senses are blundering, inaccurate, and crude. With all our boasted knowledge and skill the great mass of physical phenomena lies beyond the range of human sense. It has been said that the vast extension of human knowledge since the days of Galileo and Newton, grouped broadly under the name of science, has been chiefly the exploration of the world that lies beyond our primitive senses. The microscope is the tool that introduces us to that "unseen, unheard, unfelt, universe whose fringe we are just beginning to explore.”

II. It affords training in muscular control.-The student comes to this instrument after the greater muscles have acquired a large degree of growth. All his life the student has done things that called into service the larger muscles. Where use is made of them expression is fairly accurate and creditable. The mind is gradually seeking to bring the finer and more delicate human mechanism under proper control. It is training in skill versus strength; the light stroke at tennis versus the battering ram of the gridiron. Whether the student is proceeding analytically from the whole to the related part, or synthetically is constructing the whole from the parts, he is at work in a field where delicacy, accuracy, and precision are required, and the results will depend upon the age, maturity, and efficiency of student and teacher and upon the proper handling of the tool with which they must labor.

III. It affords technical training in precision.-Carl Snyder is authority for the statement that the aim of all scientific endeavor is to "describe natural phenomena, including all visible and invisible things, matter, life, and mind, by simple mechanical laws expressible in simple mathematical equations." To this end instruments of precision are absolute requirements. The period in the world's history during which the greatest relative progress has been made in science extends over a comparatively brief interval and coincides with the period in which instruments of accuracy and precision have been invented and used in experiments and exact measurements. In the brief span of a few hundred years more has been learned in the way of definite knowledge than in all the half-hundred centuries that preceded them. Industrial inventions, mechanical appliances and instruments of precision, underlie all modern scientific progress. They have made exact knowledge possible. Chief among them is the microscope. By means of it we have been able to establish, verify, and reduce to a mathematical certainty much of that vast body of classified knowledge known as science, and the ability properly to use this instrument marks genuine progress in the precise methods of modern research.

IV. It trains the pupil to discriminate between what is and what seems.-This lies at the basis of all training in science and leads to the higher processes of thought; comparison, abstraction, generalization, and critical definition. Isolated facts are of little value. It is only when they stand in their proper relation to each other, when each assumes its proper place in a chain of experiences, that it flashes into full significance. The adolescent has a tendency to overconfidence, to undue egoism, a state of mind that the critical study of nature is sure to relieve. Emerson may mean one thing to this student, another to that, and each with an apparently equal degree of certainty. A certain event in history may admit of several interpretations and each may appear equally worthy of credence. Critical scientific training eliminates that trait of mind that leads to undue confidence in a mere opinion and to this end the proper use of the microscope contributes a large share. With it

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