Abbildungen der Seite
PDF
EPUB

Berlin, announces the publication of a new Survey, the hydrographer of the Navy, two journal devoted exclusively to original mathe- representatives of the Royal Society of Edinmatical memoirs, the Mathematische Zeit- burgh, two representatives of the Royal Irish schrift. It is edited by Professor L. Lichten- Academy, two members nominated by the stein, with the collaboration of Professors K. British Association, and two members nomiKnopp, E. Schmidt and I. Schur and an edi- nated by the Royal Society. Since their fortorial committee consisting of Professors W. mation these committees have advised the Blaschke, L. Féjer, C. Herglotz, A. Kneser, E. council of the Royal Society on the formation Landau, O. Perron, F. Schur, E. Study and of the international unions in their respective H. Weyl. Two volumes appear annually. subjects, and nominated the delegates to the DR. EDWARD L. THORNDIKE, professor of edu

recent meeting at Brussels. The Federated cational psychology in Teachers College, Co

Council for Pure and Applied Chemistry was lumbia University, delivered an address at

also recognized as the national committee on Wesleyan University on October 14 on “Psy- that subject. chological tests for college entrance examina- The following lectures were delivered durtions."

ing the graduate summer quarter in medical DR. ALEXANDER D. BLACKADER, professor of sciences at the University of Illinois, College pharmacology and therapeutics in McGill Uni- of Medicine, Chicago, Illinois. versity, Montreal, delivered the annual ad- “Transmission of eye-defects induced in rabbits dress to the medical students on Founder's by means of lens-sensitized fowl-serum:" Michael Day, his subject being, “Our medical faculty F. Guyer, Ph.D., professor of zoology, at the Uniand the value of continued medical research." versity of Wisconsin, The late Professor Rudolf A. Witthaus, of

“Metabolic gradients:" C. M. Child, Ph.D.,

professor of zoology at the University of Chicago. the Cornell Medical College, bequeathed his

"Modes and age periods of infection in tuber. medical apparatus and scientific books to the culosis:" M. P. Ravenel, M.D., professor of precollege.

ventive medicine at the University of Missouri. WILHELM VON SIEMENS, head of the Siemens Catalase:" W. E. Burge, Ph.D., assistant proHalske Companies, is dead at Arona, Switzer

fessor of physiology at the University of Illinois. land.

“Nerve transplantation:" C. Carl Huber, M.D.,

professor of anatomy at the University of MichiNature reports that the council of the gan. Royal Society has nominated representative “Malaria with especial reference to its concommittees to deal with national questions trol:" C. C. Bass, M.D., professor of experimental connected with the international unions which medicine, Tulane University. it is intended to form under the International "Giant cells and their role in bone resorption:" Research Council. The committee for as- Leslie B. Arey, Ph.D., professor of microscopic tronomy will consist of the Astronomers

anatomy, Northwestern University., Medical School. Royal for England, Scotland and Ireland, the

“The influence of some chemical substances on Superintendent of the Nautical Almanac, six

immunity reactions:" Aaron Arkin, Ph.D., M.D.,

professor of pathology and bacteriology, Univermembers nominated by the Royal Society, six

sity of West Virginia. members nominated by the Royal Astronomical Society, two members nominated by the

The Advisory Committee of the American Royal Society of Edinburgh, two members ap Chemical Society, on the authority given it by pointed by the Royal Irish Academy and two the council, has recommended Professor W. A. members appointed by the British Astronom- Noyes as chairman of the board of editors in ical Association. The committee for geodesy charge of the scientific series of monographs, and geophysics will consist of the Astronomers and Dr. John Johnston as chairman of the Royal, the director of the Meteorological board of editors of the technological series of Office, the director-general of the Ordnance monographs recommended by the committee

The Royal Society announces that two John Foulerton studentships will shortly be awarded for original research in medicine, the improvement of the treatment of disease, and the relief of human suffering. Researches must

s must be carried out under the supervision and control of the Royal Society. The studentships are of the value of £400 each, and are tenable for three years, but may be extended to a total period of six years. Candidates must be of proved British nationality; both sexes are eligible.

EDWARD H. MACK, Ph.D. (Princeton, 1916), has returned from overseas duty and has gone to the Ohio State University as assistant professor of physical chemistry.

PROFESSOR EDWIN MORRISON, for thirteen years head of the department of physics at Earlham College, has been granted a year's leave of absence and is teaching engineering physics in the Michigan Agricultural College.

C. M. Young, formerly of the University of Kansas, has returned as professor and head of the department of mining engineering.

DR. HORST OERTEL has been appointed head of the department of pathology at McGill University.

DR. EDWARD HINDLE, Kingsley lecturer and fellow of Magdalene College, Cambridge, assistant to the Quick Professor of biology, has been elected to the chair of biology in the School of Medicine, at Cairo, Egypt, in succession to professor A. Looss. Dr. Hindle was instructor in zoology at the University of California from 1909 to 1910.

NEWS

UNIVERSITY AND EDUCATIONAL

NEWS At a recent meeting of the New York Endowment Fund Committee of the Massachusetts Institute of Technology, Mr. Coleman du Pont presiding, President R. C. MacLaurin announced that $1,500,000 had been subscribed toward the $8,000,000 endowment fund. “Mr. Smith," the anonymous donor of $7,000,000 to the institute, has agreed to give $4,000,000 to the fund if $3,000,000 is pledged by January 1, 1920.

DR. GEORGE W. CRILE, of the School of Medicine of Western Reserve University, has given $100,000 to endow a chair of surgery. Dr. Crile is chief of the surgical staff of the school. He headed the Lakeside Hospital Unit of Cleveland, one of the first American units in France.

COLUMBIA UNIVERSITY has received a gift of $6.000 for research work in food chemistry.

PROFESSOR SAMUEL N. SPRING has returned to the United States for the first term of the present college year to teach silviculture, forest law and policy in the Department of Forestry at the University of Missouri. He will resume his work as professor of silviculture at Cornell University on January 1, being at present on leave of absence.

RICHARD M. FIELD has been appointed assistant professor of paleontology and historical geology at Brown University. He also continues his association with the research staff of the Museum of Comparative Zoology at Cambridge.

DISCUSSION AND CORRESPONDENCE DOUBLE USE OF THE TERM ACCELERATION

TO THE EDITOR OF SCIENCE: The use of clear and distinct meanings of terms has not kept pace with the progress in science. One repeatedly hears appeals for the stardardization of the meanings of terms. Great confusion arises when different writers use the same term with entirely different meanings. In the writer's opinion, it is quite as important to fix the definitions of the fundamental terms as it is to fix the units; scientific organizations ought to get together, arrive at some conclusion, and then appeal to the Bureau of Standards to officially standardize such definitions as they do the units.

A notable case which gives rise to much confusion, is the term acceleration. The engineer always used this term to mean the rate of increase of speed, that is, velocity divided by time, hence its dimensions are LT-2; it is measured in feet (or meters) per

second per second. The physicists, however, gives energy; hence torque has the dimension who use this term in the same sense, also use of energy, when as a fact they are two it indiscriminately in an entirely different entirely different physical quantities. The sense, namely, to express a change of direction reason for this inconsistency is that in this of a moving body, without any regard as to system an angle has no dimension, yet we whether there is any change in speed or not know that torque (which is not energy) when Thus the physicist will refer to the existence multiplied by an angle gives energy, hence an of acceleration when to the engineer there is angle must have some dimensions. This is none. A case in point is the revolution of a one of the serious shortcomings of that sysfly wheel at a constant speed, the rim of which tem. It is also the cause of the double use to the physicist is being constantly acceler- of the term acceleration. ated while to the engineer there is no acceler- When force is defined as mass X acceleraation, as the speed is constant.

tion, it should be understood that the angle The physicist argues, and quite correctly, is eliminated by being zero; acceleraton is that a moving body represents a vector quan- then always a change of speed, the sense in tity, as it has both speed and direction. The which the engineer uses that term. A new same external force applied to such a moving term should be used when the force is at body will change either the speed or the right angles to the direction of motion, in direction, depending upon the relative direc- which case it adds no energy to the system tions of that force and of the moving body and produces no change in speed, but merely But as force is defined as mass X accelera- a change of direction. For any angle betion, the physicist, apparently forgetting the tween 0 and 90° no further distinction is redifference between pure and applied mathe- quired as the resultant then is always the matics, methodically divides this force by the vector sum of the two components at 0 mass and calls the quotient acceleration. It and 90°. simplifies his mathematics.

Such a distinction between these two differSuch blind applications of pure mathe- ent meanings of acceleration is very desirable matics, however, sometimes lead to absurd in order that the engineer and the physicist results. In the present case, if this external may always understand each other without force is applied in the direction of the movement of the body, it adds energy to the

CARL HERING moving system, as in the case of a falling

PHILADELPHIA, body. This is the sense in which engineers

October 7, 1919 use the term acceleration. But if this ex

AN ORNITHOMIMID DINOSAUR IN THE ternal force is applied perpendicularly to the

POTOMAC OF MARYLAND direction of motion, no energy whatever is

A RECENT study of some of the dinosaur added to the moving system, as in the case specimens in the United States of bodies rotating around a center.

Museum from the Arundel formation of The importance of this distinction is shown Maryland has led to a discovery of more than in the common term foot-pounds, the product ordinary interest. It is the recognition of an of feet and pounds (of force). If both are in undoubted Ornithomimid dinosaur, the first the same direction this product represents representative of this group to be found east energy, while if perpendicular to each other of the Rocky Mountain States, or geologically it represents torque, which is decidedly not below the Judith River formation of the energy. The writer long ago suggested to use Upper Cretaceous. the term pound-feet, when it refers to torque, The materials on which this determination in order to call attention to the difference. rests consist of various bones of the hind foot,

In the MLT system of dimension of phys- pertaining to more than one individual. ical quantities, force multiplied by length Originally some of these elements were in

The Arundel formation is regarded by the most competent authorities to be Lower Cretaceous in age, and equally eminent paleontologists have correlated the Arundel fauna with the Morrison fauna of the Rocky Mountain region so that the conflicting evidence of these later discoveries promises to be of both paleontological and geological interest.

CHARLES W. GILMORE U. S. NATIONAL MUSEUM,

October 4, 1919

cluded among the cotypes on which Marsh: founded the species Allosaurus medius, but in 1911 they were removed from the Theropoda by Lull2 to the Ornithopoda, and with other bones made the cotypes of the new species Dryosaurus grandis. I had never been satisfied in my own mind that these bones pertained to a herbivorous dinosaur but it was only recently that I have had the opportunity of comparing them with Ornithomimid materials. Through the courtesy of Mr. Walter Granger, of the American Museum of Natural History, I was enabled to compare these foot bones with those of the genotype of Struthomimus altus (Lambe) and other Ornithomimid foot materials from the Belly River and Edmonton formations, and in every instance have found such close resemblances as to leave no doubt of their Ornithomimid affinities, a view concurred in by Mr. Barnum Brown, of the above institution.

In an extended paper on the carnivorous Dinosauria contained in the collections of the U. S. National Museum, now in press, these bones are discussed in detail and are there tentatively assigned to the genus Ornithomimus.

The recognition of this Ornithomimid dinosaur led to an investigation of the other members of the Arundel fauna and the preliminary study appears to show that there are at least three other dinosaurian forms having Upper Cretaceous affinities.

The presence of dinosaurs with Upper Cretaceous affinities, associated with Sauropod dinosaurs (Pleurocælus) is a combination previously unknown, but whether it means that the Sauropoda lived on to a much later time than we had previously suspected or whether we have in these dinosaurs of Upper Cretaceous affinities the progenitors of the Judith River (Belly River) forms, I shall reserve judgment until a critical study of the whole fauna, now in preparation, is completed.

1 Amer. Jour, of Sci. (III.), Vol. XXXV., 1888, p. 93.

2 Geol. Survey of Maryland, Lower Cretaceous, 1911, pp. 204–206, Fig. 7; Pl. 20, Figs. 1-4.

AN ELEPHANT WITH FOUR TUSKS TO THE EDITOR OF SCIENCE: I have thought that the accompanying note with regard to the “elephant with four tusks," and its illustration would be interesting for SCIENCE to reproduce as an extraordinary record tucked away in a rather remote publication.

Picture and text. are taken from « Sudan Notes and Records.” Volume 2. number 3, July, 1919, page 231, and the account is there printed in Arabic with the accompanying translation. I am sure this will engage the attention of our many mammalogists and paleontologists.

JOHN M. CLARKE On the 18th May, 1917, I went out shooting in the district of Sheikh Ako Mangara, in the Markaz of Yambio, in the village of Wakila Marbo, on the borders between Tembura and Yambio districts.

I met a herd of elephant which I followed, searching for a good one to shoot. I kept following them until they stopped near a pool of water, where they began to drink and throw mud on themselves. I was in hiding behind a tree about fifteen yards from them looking at them, when I saw an elephant with four tusks as roughly represented in the attached sketch.

The left tusk was the bigger and had the usual direction, but the direction of the small tusk was downwards and came out from under the big one. It was round, and its thickness was about 21 inches.

The direction of the right tusk was downwards and the small tusk came out from under it in the usual direction, but it was small like the other one.

I did not know that this elephant was so valuable and for this reason I did not try to shoot it, although the Ombashi and the soldier who were with me told me to shoot it, but I refused. This is all the story.

ABD EL-FARAG ALI, M.A. YAMBIO,

February 17, 1919

QUOTATIONS THE WORK OF THE BRITISH ASSOCIATION

FOR THE ADVANCEMENT OF SCIENCE Your leading article of this morning expresses some dissatisfaction which even those who have best cause to be satisfied with the recent meeting will readily share. You sneer at the “vast sum ” of £1,300 provided for research at the outcome of the meeting. We all share your obvious wish that it were much larger, and the treasurer especially made that desire clear at one of the evening meetings. Any hint you may give us how it may be increased will be gratefully received. Meanwhile it is possible that its exact significance is not fully understood. It represents, so to speak, the extra charges for heating and lighting when a big factory is run overtime by voluntary workers. The main expenses of the scientific organization of the country, including the salaries of professors and demonstrators, are met in quite other ways. Some members of ths large staff find that they have time and energy to work overtme—to conduct some research which has occurred to them as desirable if only a piece of apparatus can be provided or the expenses of a series of computations met. They ask for no addition to their salaries for this work, though such additions could in many cases be reasonably

defended. They come to the British Association only for out-of-pocket expenses. The value of the work thus done is enormous, and if fully remunerated would represent a sum many times greater than that actually devoted to it.

It follows that there is a limit to possible expenditure of this kind. I do not mean to suggest that has been reached, but clearly the unpaid overtime obtained from a given staff has its limits. There comes a point at which more work can be got only by adding to the staff, and at this point the British Association generally hands over the matter to some other body. Thus the beginnings of our Great National Physical Laboratory, now added to the scientific resources of the nation, may be traced in the earnest but unassuming work done by the British Association many years ago when in your own words "some of the best brains in Great Britain met in solemn conclave to allot the vast sum ” of about £1,000, only a fraction of which could be devoted to the fundamental work of fixing accurately the electrical and other standards. The war has accustomed us to the huge sums which are apparently available for destruction: it is a commonplace that the beginnings of the most important constructive work are usually small. Is your sneer altogether appropriate?

With your suggestions that the camp followers should be dismissed and the discussions specially directed to the “ technical methods on which the progress of science depends " I do not find myself altogether in sympathy. We owe much to the camp followers, even beyond the money they provide for research; and the experts can meet at the Royal Society for technical discussions. But I scarcely know whether you would welcome a reconsideration of the declared objects of the British Association in your columns: at any rate, I hesitate to enter on so large a field without some indication of permission. On the point you consider most vital, that the Association should "insist on the advancement of science simply as knowledge, and not merely as a means to practical utilities,” we are all fully agreed, as a glance

« ZurückWeiter »