sidered these new phases of atomic structure of sufficient value to warrant an investigation; second, the great majority of science teachers received no college training in the subject of electrons; third, up to recent date but little information has been available of adequate clarity to be instructive enough to serve as a teaching basis for the new atom.

But teachers cannot hide behind such excuses for long. The new science of matter may change ere long and be out of fashion, but this new hypothesis is ever being crowded into our present existence and teachers competently or incompetently, should make it their business to find out something about this new thought, which afterward can be confirmed or denied as the case may be. Then too, so long as teaching is a profession it will have before it the contact of youth struggling with the facts of modern thought. Should science be explained away with a gesture? Chem-. istry is not as important as Matter.

Upon many occasions the statement has been made that our scientific courses in the secondary schools are formulated and built up by what the colleges require and hence that, unless colleges insist that entering students - know something about the Electronic Hypothesis of Matter, the high school teacher should consider it no concern of his. Ninety per cent of the teachers canvassed reported, that to the best of their knowledge, colleges with which they were familiar, do not require of high school students a conception of the Electron Theory. Nevertheless these same teachers are realizing that there is a growing tendency among college instructors to expect that, when the term "electron" is mentioned in their classes, the ex-high school student will be able to associate with the word some simple connective ideas. Naturally practice varies in various colleges. Some central and western colleges and several colleges in New England according to the report, do not require their entering pupils to give details of the new atom, but they do expect that these same pupils have brought with them something beyond the atom of Dalton and are not ignorant of the modern trend of thought.

There is too much diversity of opinion existant between teachers in secondary schools and in colleges to argue here the wisdom of requiring the Theory for entrance to college. Some college instructors feel that the student in high school may gather false notions of the electron which would take time to correct and hence the subject should be left to them to develop. Other college instructors take a broader viewpoint and state that it is not wise for colleges to demand of high school students a knowledge of the Theory, since on the whole, high school instructors have had little opportunity to know much about it, and that too, the usual numerous and diversified tasks of the high school teacher make this new demand an additional load. A majority of secondary school teachers are quite in accord with these views in that $2 per cent of them reported in the ques

tionnaire that it would be unwise for colleges to demand that students retain more than a few simple ideas of the Theory. Teachers as a whole do not challenge the right of college instructors to expect pupils to understand that atoms are divisible and that matter is perhaps electronic, so long as they hold uppermost the realization that the minds before them are of a younger generation than theirs. This would mean, then, but an elementary knowledge of the new principles.

However, when teachers were asked if the subject should be treated by colleges solely, opinion was about equally divided among them for 47 per cent considered it a subject for the colleges alone, and 51 per cent were of contrary opinion. The cities outside of New England took, perhaps, a more progressive attitude for 76 per cent believed that beginnings should be made in the high school. If all our high school students were college preparatory, the discussion might come to an end and for some time to come let the colleges handle and dictate the problem. But a large part of our science students are not college preparatory. What of them? We are not believers in the segregation of knowledge, we are gregariously inclined and that is democratic, American like. We believe in letting the light of knowledge fall upon any willing recipient of that light. Hence electrons must be presented in our secondary schools so that the general student may have some idea of the modern conceptions of matter as well as his college inclined friends. This is the attitude as expressed by 75 per cent of the teachers. We are purposely educating the average student to enjoy a richer relationship of the problems of science to human welfare to think, to read, to discuss these problems more intelligently, and to take his place in world affairs, though, perhaps as is believed, not so richly endowed with a broad vision as his college friends.

From the viewpoint of the high school student, would a knowledge of electrons benefit him later in his college science? There is no marked opinion among teachers about this though 60 per cent are of the impression that enough of the significance of electrons could be given in the short time that might be allotted to the work to benefit the student going to college— the remaining percentage being of a contrary mind. Really at best thought opinions on this point can only be considered a guess, since no returns are available to indicate otherwise. However, some educational psychology and common sense combined would explain away this difficulty.

Certainly no theory, those portions of the electron of which little is known and still hypothetical, should be given in Chemistry in secondary schools. That is for research. Overflow your course with theoretical statements which are oftentimes haphazardly given in elementary work and you are in a sure way to plant in the minds of your students, wrong conceptions which they take with them in later study. Early in the course the facts of Electron Theory can be used. Atoms are now divisible and

here should begin the explanation of the electrical composition of the elements, showing each element of the more common and the lower atomic number, with the possible arrangement of the electrons about the nucleus. With the new arrangement of the atom present, the instructor has now a more satisfying explanation for valence, ionization and the electro-chemical series, oxidation and reduction, temperature reactions in water solutions, the ionic reactions with acids, bases and salts, and the new periodic grouping of the elements according to their atomic number. The size of the nucleus and the distance of the valence electron determines what sort of atom it is-what element it belongs to and therefore its noticeable properties. Teachers are continually pointing out that the fundamentals of chemical reactions and valence are principles that have been hard for the pupil to visualize. They may find it easier to visualize these fundamentals by explaining some of the electronic concepts of the elements.

In conclusion, it is enough to say that the chemistry teacher has more than sufficient facts that have been established from the Theory for him to utilize throughout his course in Chemistry and withal, simple yet fundamental enough to keep away from theory. The wise teacher should not hesitate to present this New Theory of the Electron to his students. It is becoming the background for new thinking in the science of matter and to the alert student a new inspiration to know the Truth—and that is the guiding principle of all scientific endeavor.

REPORT ON QUESTIONNAIRE SENT TO CHEMISTRY TEACHERS CONCERNING THE ADVISABILITY OF INCLUDING THE ELECTRON THEORY IN HIGH SCHOOL CHEMISTRY

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12. Is this a subject for only the colleges to treat?

13. Is it, in your opinion, wise for college instructors to demand of high school students a knowledge of the Theory?

14. Are you familiar enough with present college instruction to report whether or not a knowledge of this Theory is actually required of high school students?

15.* If so, in what colleges?

16.* Are there any textbooks containing a presentation of this Theory in an elementary form?

17.* What books treating on this subject would you recommend to high school students for reading?

18. Do you believe that high school instructors feel competent to present this subject successfully?

19. Do you believe that the student could obtain enough of the Theory in the short time that would be allotted to the subject to benefit him later in his college Chemistry?

20. Are you teaching any part of the Theory to your chemistry classes?

*See report.

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Correlation Problem

Be sure to send your criticisms on the enclosed outlines at your earliest convenience. The committee will deeply appreciate it.

THE VAPOR DENSITY OF STEAM*

W. L. EVANS, J. E. DAY, C. S. PEASE AND G. D. BLAND, OHIO STATE UNIVERSITY, COLUMBUS, OHIO

The classical experiments of Berzelius and Dumas by means of which these investigators showed that the elements hydrogen and oxygen unite to form water in the ratio of 1: 7.98, respectively, do not furnish sufficient data to enable the beginner in chemistry to determine the exact formula for water. In addition to this quantitative data with reference to the composition of water, it is necessary that the vapor density of the compound be known in order that its molecular weight may be calculated. Obviously it is quite impractical for the beginner to actually weigh one liter of steam. However, we have found that this difficulty is overcome by transferring a known volume of steam into a small calcium chloride tube which has been previously weighed. The following are the details of the experiment.

An apparatus is arranged in accordance with Fig. 1. Before the heating of the brine (CaCl2) is begun, the U-tube is disconnected at B and C, and the soda lime-calcium chloride tube at A, the precaution being taken to close these tubes with the well known plugs made of glass rodding and rubber tubing. The U-tube is now weighed and then attached to the straight calcium chloride tube at C.

The screw clamp should be opened. When the temperature of the brine

*Read before the Division of Chemical Education of the American Chemical Society at the Milwaukee Meeting, Sept. 13, 1923.