to forty-three weeks. One curve of growth of forty-three weeks is but a continued curve of thirty weeks stated by Professor McCollum in the Journal of the American Medical Association of May 12, 1917, as having been presented by him before the Harvey Society, January 13, 1917. This experiment has actually been completed at least eleven weeks before Professor McCollum left the University of Wisconsin. In fact some of the curves bear a serial number and legend the same-and none bear a higher or lower serial number-as curves of similar experiments previously published by him from this institution. Again it is significant that Professor McCollum upon severing his relations with the University of Wisconsin removed from the campus all station records accumulated by him, and some of those of other members of the staff, without the permission or knowledge of the staff, or administrators. It is recognized that a university professor doing research work on his own initiative and on his own problems is entitled to the exclusive possession of his notes, but no such exclusive right is recognized in the case of experimentstation workers even to their own notes on continuing projects carried out under federal grants for an indeterminate period. Whatever may be said in denial, these are the facts. The first two are directly supported by evidence submitted in articles published by the aforementioned authors themselves. third, first mentioned in Professor Hart's statement, they have already not seen fit to deny. The Except for the purpose of bringing out, for the benefit of those who may be concerned in the future, not only a case of transgression of professional courtesy but of professional ethics. as well, the writer is not inclined to present arguments in his own behalf, especially in a matter of such small personal moment as credit for the scientific article. For the major portion of the time while the vitamine preparations in the research in question were being made and their stability was being tested Professor McCollum did not even know what was being done, or how it was done; he fed the rats. In fact, the 1916 report of the Director of the Wisconsin Experiment Station gives the writer of this note exclusive credit for activities in this field. My acquaintances know full well what Professor McCollum's real personal opinion of me was before his transgressions, in an attempt to hamper further experimental work, called forth deniable but unrefutable charges. In place of a lengthy presentation of details actually called for by the indirect question aimed at my veracity and Professor Hart's veracity, but really best forgotten, there have been presented a few general facts in final answer instead. H. STEENBOCK UNIVERSITY OF WISCONSIN TO THE EDITOR OF SCIENCE: Please accept my thanks for submitting to me the attack upon my character by Mr. Steenbock, in order that my reply may be printed together with it. I do not care to be a party to an undignified dispute over the question of the accuracy of the accusations which are contained in this letter, and shall not attempt an elaborate explanation of details. For the benefit of such readers as are not familiar with the original publications of Hart, Steenbock and myself, which will, I feel assured, suffice to prevent my colleagues in the field of biochemistry from giving any serious consideration to this matter, I shall present, briefly, a few facts which will enable them to see the matter of this controversy in its proper perspective. I shall hereafter take no notice of further utterances of this character. Any one who will take the trouble to examine the publications which have emanated from the laboratory of agricultural chemistry of the University of Wisconsin during the last ten years can easily form an opinion for himself as to who was initiating the work in nutrition investigations during that period. When I left the University of Wisconsin in the summer of 1917, I took with me all the records of the experimental work with my rat colony but not any notes other than my own. No one who had not been closely identified with the work could possibly have correlated the many results, some of which were worthy of publication, and others, for one reason or another, not satisfactory from which to draw conclusions. Furthermore, it will be generally conceded that no one but the experimentor himself has the right to the interpretation of his data, for he must be responsible for the correctness of such interpretation. I find on reexamination of the charts in the paper by Miss Simmonds and myself in the Journal of Biological Chemistry, 1917, XXXIII., p. 303, that several of the curves of growth were secured in experiments carried out before our removal to Baltimore. I regret that mention was not made of this fact. Most of our papers contain data which was not secured from a series of experiments carried out simultaneously. The later experiments are in most cases planned in the light of the outcome of the earlier ones, the work being continued until a complete demonstration of some principle is secured. No injustice was intended or will in future be done to the University of Wisconsin by withholding proper credit for the facilities which made the work possible. The serial number of an experiment signifies the period when a certain ration was planned and entered in our notes and does not throw any light on when the feeding trial was made. In 1907 I began to build up my rat colony at the University of Wisconsin for the purpose of studying the problem of the cause of the failure of young animals to grow when restricted to diets consisting of purified proteins, starch, sugars, fats and suitable inorganic salt mixtures. No one in this country at that time had any interest in the enterprise except myself. My first publication describing this work appeared in 1909, and antedated that of any other of similar character by two years. It required five years of fruitless experimenting before the first important observation was made which gave a clue to the solution of the problem. In 1912, Miss Davis and I first observed the peculiar growth-promoting properties of butter fat. We had a ration which we supposed consisted of food substances essentially pure, with which we could induce growth when butter fat was in cluded to the extent of five per cent., whereas the same food mixture containing such a fat as olive oil or lard did not induce any growth. For a time we believed that butter fat contained the only chemically unidentified dietary essential necessary for the promotion of growth or the maintenance of health in a mammal. By 1915, Miss Davis and I, after making several hundred experimental feeding trials variously modified, were forced to the conclusion that a second unknown dietary essential had been contained in the 20 per cent. of supposedly purified milk sugar, which had formed a constant constituent of many of our early diets; we thereupon propose a new working hypothesis concerning what constitutes an adequate diet. This postulates the necessity of two dietary essentials of unknown chemical nature. After a long series of experiments planned to show the distribution of these two substances in natural food-stuffs, it was found that one of them is associated with certain fats, whereas the other is never associated with fats of either animal or vegetable origin. The latter is soluble in water, the former readily soluble in fats. Miss Kennedy and I, therefore, proposed the terms fat-soluble A and water-soluble B as provisional names pending such a time as we should learn enough about their nature to be able to give them names which would be suited to their peculiar structure, and fit in with the nomenclature of organic chemistry. About two thousand feeding experiments have now been completed, each lasting between six weeks and two years. These were all interpreted in the light of our working hypothesis described above, and also in the light of the composition of the proteins as revealed by the studies of Fischer, Abderhalden, Osborne and others, and have made clear the nature of the dietary deficiencies of several representatives of each of the several classes of natural foods, seeds, tubers, roots, leaves, meats, eggs and milk. These results have made possible important generalizations, which must eventually lead to great improvement in the health of large groups of peoples who are now suffering from malnutrition, due to their living on poorly constituted diets, and also to greater efficiency in the use of feeding-stuffs in animal production. Our solution of the problem of successfully feeding diets of purified foodstuffs together with the two unidentified food essentials, fatsoluble A and water-soluble B, greatly simplified the study of the problem of isolating the latter substances. Indeed without it the study of this problem can scarcely succeed. My associates and I have further simplified the problem of their isolation by the demonstration that similar "protecting" substances do not exist for the diseases scurvy and pellagra. It had become a widely accepted belief that there existed not less than four such unknown dietary essentials, one for the prevention of beri-beri, another each for scurvy, pellagra and for rickets. This belief rested on the "vitamine" hypothesis of Funk. I need not here dwell upon the important studies of Eijkmann, Fraser and Stanton, Stepp, Holst, Funk, Williams, Osborne and Mendel, and of Goldberger, a critical study of whose papers greatly aided us in the planning of our experimental diets and in the interpretation of our results. During my stay at the University of Wisconsin nobody had anything to do with independent work with my rat colony, except in a small way an independent study was carried on by Mr. V. E. Nelson during the months just preceding July, 1917. I reiterate my statement in my reply to Professor Hart in SCIENCE for March 8, that the work which they charged I had made dishonest use of, which was participated in by Mr. Steenbock, was planned entirely by me, and was carried out by him as directed, in the capacity of an assistant. He was not consulted about the interpretation of the data in the paper by McCollum and Simmonds (Jour. Biol. Chem., January, 1917), because his personal attitude towards me before I left Wisconsin made impossible a joint preparation of the paper, and he was therefore given credit for the preparation of the materials employed in the experiments instead of being made joint author, as I should have been glad to have made him under other circumstances. When one leaves an institution after having made observations of a fundamental character, and having for several years made use of these in the development of new and important lines of research, his colleagues who remain behind have, of course, a right to continue investigation in this field, just as any one located elsewhere has the right to take advantage of the observations of others, and attempt to further the acquisition of knowledge. There is no property right in research or its results so long as it is incomplete and not protected by patent. Some proceed on this theory, attempting the while to perfect details, and to add some element of originality, and to give their work the mark of independent thought. Others prefer to spend their time in making experiments of an exploratory character, at the risk of doing much unprofitable work in order to make some observation which will open up a new field of investigation which they may follow with profit. A few prefer to attempt to bring into disrepute some investigator who has opened up a new field of research when he has reached a point where much further work remains to be done, which is obvious to every one who studies his published results, in the hope that they may thereby so discredit him that his work will be interfered with, with a view to making possible the reaping of a harvest of opportunity which his absence from the field would make possible. Many believing that the author of the first important observation has the right to be allowed to develop the new field without annoyance, refuse, from a sense of self-respect, to pounce upon, and, in haste, complete what another is doing, when a study of fundamental nature makes possible a new type of investigation. Judgment as to which course one should pursue will, of course, be determined by the standards of the individual. BALTIMORE, MD. E. V. MCCOLLUM THE WORLD'S CALENDAR TO THE EDITOR OF SCIENCE: A communication by W. J. Spillman in SCIENCE of May 17 discloses the fact that a bill was introduced in the Congress on April 16 with the object of reforming the world's calendar, by Honorable J. M. C. Smith, of Michigan. It is gratifying to learn that the movement for Calendar Reform is thus taking on definite shape; and also that, from the writer's viewpoint, the bill referred to embodies the feature of dividing the year into thirteen lunar months, thus assigning to the moon her rightful place in determining her share of time division in the calendar. It would appear to be sufficiently obvious without special mention, that it must be futile for any individual government to undertake a reform of the world's calendar without the cooperation of the other principal civilized nations; and that any legislation that may now be projected along that line should be with the object of securing such cooperation. It may be suggested also that the movement might better be deferred until the present world agitation shall have subsided. T. G. DABNEY CELLULOID FOR COVER GLASSES TO THE EDITOR OF SCIENCE: War conditions are causing many substitutes to be used, and even I was forced to one by the scarcity of cover glasses for microscopic work. I found that sheet celluloid can very well be used in place of the glass, the fiber thereof being practically negligible for beginning work. I take sheet celluloid, cut strips about the width of the slide, iron these strips flat (place the heated iron over each part but do not rub, for rubbing the iron causes other streaks), and then cut the strip into small squares. In addition to being unbreakable and so quite durable and inexpensive, they can not scratch the lens by the pupil running the objective into the coverslip, as beginners are prone to do with all cautions about such dangers forewarning them. Other science teachers may find this expedient worth trying. F. A. VARRELMAN LOWELL HIGH SCHOOL, SAN FRANCISCO, CALIF. AN ABSOLUTE SCALE FOR RECORDING TO THE EDITOR of Science: I think the suggestion of Dr. Marvin in a recent number of SCIENCE (15 March, 1918) with reference to the CENTRAL EXPERIMENTAL FARM, SCIENTIFIC BOOKS Calculus. By HERMAN W. MARCH, Ph.D., Assistant Professor of Mathematics, University of Wisconsin, and HENRY C. WOLFF, Ph.D., Assistant Professor of Mathematics, University of Wisconsin. McGraw-Hill Book Company, New York, 1917. Pp. xvi + 360. Differential and Integral Calculus. By CLYDE E. LOVE, Ph.D., Assistant Professor of Mathematics, University of Michigan. The Macmillan Company, New York, 1916. Pp. xviii+ 343. Plane Trigonometry with Tables. By EUGENE HENRY BARKER, Head of the Department of Mathematics, Polytechnic High School, Los Angeles, California. P. Blakiston's Son and Co., Philadelphia, 1917. Pp. 172. College Algebra. By ERNEST BROWN SKINNER, Assistant Professor of Mathematics, University of Wisconsin. The Macmillan Company, New York, 1917. Pp. vi + 263. Projective Geometry. By L. WAYLAND DOWLING, Ph.D., Associate Professor of Mathematics, University of Wisconsin. McGrawHill Book Company, New York, 1917. Pp. xiii +215. Elliptic Integrals. By HARRIS HANCOCK, Professor of Mathematics in the University of Cincinnati. John Wiley and Sons, New York, 1917. Pp. 104. Of the making of many text-books of mathematics for colleges and secondary schools there is not only no end but no very evident diminution. The phenomenon is interesting, especially in view of the gravity of the times so unfavorable to the customary pursuits of scholars. No doubt the explanation involves a wide variety of considerations. One of these is the purely commercial competition among publishers who invite cooperation of teachers in the making of books. Another is the fact of a certain inertia acquired before the war: for example, no less than four of the above-listed volumes belong to series of publications initiated in times of peace or at all events prior to the entry of the United States into the world conflict. A third consideration relates to numbers: the number of persons in the country who are devoted to the teaching of mathematics or to mathematical research or to both is large; it is absolutely large and it is large relatively to the number of those similarly engaged a generation or two ago; the membership of the American Mathematical Society includes more than seven hundred; that of the recently organized Mathematical Association of America, more than a thousand; and there are in various sections of the country other flourishing associations of teachers of mathematics: it goes without saying that where there are many persons competent to write books many books will be written. No doubt the more intimate personal motives to the writing of mathematical text-books are various. The hope of pecuniary reward is probably not very effective, at least not effective with many, if by hope we are to understand desire plus expectation. What may be called the reputational motive is doubtless more powerful: there is a general expectation that college and university instructors will be productive scholars; owing to a variety of circumstances the production of text-books is apt to seem an easier, albeit a less effective, way to meet such expectation than is the way of research. Then there is the altruistic motive the impulse to serve; it is certain that this motive is frequently present and sometimes dominant: mathematical text-books are sometimes written to advance the cause of mathematical education. It is probable One of that the principal motive to the kind of activity in question is really hedonic, consisting in the peculiar pleasure that is felt in trying to perform an approved task of great difficulty or to view the matter in another aspect-in trying to win, in competition, an exceedingly difficult game. Surely there is here ample room for the play of that motive, for it is not easy to imagine an undertaking more beset with difficulties than is the writing of a mathematical text-book that is to be at once excellent in quality and successful in its appeal for public approval. The suffrages of teachers must be won. But teachers vary enormously in respect of scientific competence. The extremes are widely sundered. them is represented by the reactionaries, by those whose knowledge is less a knowledge of subject-matter than of traditional ways of presenting it and who are naturally opposed to every innovation of theme or of method. The other extreme is represented by the fadist, the ultra modern, the clamorous reformer whose creed is that whatever is is bad, who confuses the novel with the good, and pursues the new, because it is new, with irrational zeal. Another difficulty is the question of size: how big ought the book to be? The question is puzzling because in our schools there is no uniformity of standard or of practise regarding the amount of time devoted to a given subject. A yet more perplexing question is that of presuppositions: what degree of intel lectual maturity and what degree of scientific preparation ought to be presupposed in the pupils for whom the book is designed? Such is our lack of uniformity of standards that an answer that is right for one institution or one locality will be wrong for another, and so the author is obliged to guess and to compromise. Not the least interesting part of the game, and a part that is especially fascinating, because it can never be managed quite successfully, is the part requiring the author to minister at once to the culture interests and the efficiency interests of his readers; for the two interests can not be harmonized nor made identical by the easy device of stoutly denying their difference. Again, the necessity of adjusting the |