DR. C. CHILTON, professor of biology at Canterbury College, New Zealand, has been elected an honorary member of the Royal Society of New South Wales.

PROFESSOR AARON NICHOLAS SKINNER, formerly professor of mathematics at the U. S. Naval Academy and assistant astronomer of the Naval Observatory, died on August 14, in his seventy-fourth year.

MR. ROBERT CHRISTIAN MCKINNEY, for many years a member of the topographic branch of the U. S. Geological Survey, has died on July 27, at the age of sixty-two years.

COLONEL BERTRAM HOPKINS, professor of mechanism and applied mechanics in Cambridge University, died on August 26 in an aeroplane accident.

PROFESSOR O. HENRICI, F.R.S., emeritus professor of mechanics and mathematics in the Central Technical College of the City and Guilds of London Institute, died on August 10, at the age of seventy-eight years.

STONEHENGE, the famous Druid monument, which has always been in the hands of private owners, has been presented to the British nation by C. H. E. Chubb, who purchased it in

1915.

THE statutory meeting of the general committee of the British Association for the Advancement of Science, was held in London in July, and at this meeting much disappointment was expressed that for the second year in succession it has been found impossible to arrange for an ordinary meeting. A resolution was passed unanimously asking the council to arrange for a meeting in London next year, if it should prove impossible to arrange to meet at Bournemouth. The question as to the type of meeting which it was desirable to hold was left to the council to decide.

THE Illuminating Engineering Society will hold its annual convention at the Engineering Societies Building, New York, on October 10, 1918. War-time lighting economies, the use of better lighting in speeding up war production and manufactures, the lighting of camps, effect of lighting curtailment on crime, and automobile headlight laws will be discussed.

THE Association of American Agricultural Colleges and Experiment Stations will hold its thirty-second annual convention at the Southern Hotel, Baltimore, Md., November 13-15.

THE Council of the Royal Microscopical Society announces that the high cost of printing and the growing scarcity of paper have compelled them to reduce the issue of the Journal to four numbers per annum instead of six. The revenue account of the society for 1917 showed an excess of expenditure over income of £141.

THE Committee of organization for the South American Conference on Hygiene, Microbiology and Pathology, to be presided over by Professor Couto, has decided on Rio de Janeiro for the inaugural session. It will convene on October 15. The previous meeting was held at Buenos Aires in September, 1916.

THE Journal of the American Medical Association states that the commission sent by the National Public Health Service to study epidemic diseases in northern Argentina is under the leadership of Professor Kraus, director of the Instituto Nacional Bacteriologico. The other members of the commission are Drs. de la Vega, Battaglia, Barbara, and Fischer, with several bacteriologists, guardas sanitarios and attendants. The epidemic of pneumonia at Jujuy has almost completely died out, but the mortality reached 30 per cent. In the Galpon and Molinos districts there have been cases suspicious of bubonic plague and the commission is to investigate these foci. A large squadron is equipped for rat destruction. at these places. The main interest for the expedition, however, is the investigation of typhus, for exanthematous typhus has never been reported before in Argentina. The suspicious cases which the commission is to study have occurred at Iruya, near the frontier of Bolivia, in a poor, mountainous zone with little communication with the outside.

Nature states that the position of Great Britain as regard the supply of optical glass at the outbreak of the war is often not clearly understood. Optical glass has been manufac

tured in this country since 1848 by Messrs. Chance Bros., and Co., Birmingham. When the supply of German glass was cut off in 1914, the experience gained by this firm became an important national asset, and through it an acute situation was saved. Messrs. Chance have supplied nearly the whole of the optical glass required for instruments used by British forces during the war, and also much of the requirements of the Allies, without any assistance from the formula determined by the Glass Research Committee of the Institute of Chemistry. This committee rendered invaluable aid to the manufacture of scientific and heat-resisting glassware, but the needs of optical-instrument makers were met independently by Messrs. Chance, whose output since. the outbreak of hostilities has increased twenty-fold. Without their seventy years' experience it would have been very difficult to have produced the supply of optical glass imperatively demanded by conditions of war.

PRESIDENT WILSON has issued a proclamation establishing three new national forests in the East-the White Mountain, in Maine and New Hampshire, the Shenandoah, in Virginia and West Virginia, and the Natural Bridge, in Virginia. The White Mountain National Forest is located in Grafton, Carroll and Coos counties, N. H., and Oxford county, Me. The Government has actually taken title to about 267,000 acres, and in addition about 124,000 acres more have been approved for purchase, making a total of about 391,000 acres under Federal protection. This forest protects in part the watersheds of the Androscoggin, Saco, Connecticut and Ammonoosuc rivers. The Shenandoah National Forest is situated in Rockingham, Augusta, Bath and Highland counties, Va., and Pendleton county, W. Va. The government has acquired to date slightly in excess of 100,000 acres and an additional area of approximately 65,000 acres has been approved for purchase, making a total of approximately 165,000 acres under Federal protection. The forest is for the most part on the watershed of the Shenandoah river and it also protects a portion of the watersheds of the Potomac and the James.

The Natural Bridge National Forest is situated in Rockingham, Nelson, Amherst, Botetourt and Bedford counties, Va. The federal government has actually acquired title to a little over 73,000 acres, and an additional area of approximately 29,000 acres has been approved for purchase. The forest, which protects a portion of the watershed of the James river, does not include the Natural Bridge, but this scenic feature is within three or four miles of the boundary.

As a means of combating tuberculosis and other communicable diseases besides elevating the general health conditions throughout the state, the Oklahoma Association for the Prevention of Tuberculosis is conducting a series of general surveys of cities throughout the state. The surveys are in charge of Mr. P. Horowitz, of the department of biology and public health, Massachusetts Institute of Technology, and Dr. Gayfree Ellison, professor of bacteriology and hygiene of the University of Oklahoma. The investigators are assisted by members of the executive and nursing staff of the State Association, as well as by the staff of the State Board of Health and the Board of Argiculture. The surveys, which began on April 1, are continued through the month of September. The following towns are included in the study: Oklahoma City, Tulsa, Muskogee, Enid, Shawnee, Bartlesville, Ardmore, Chickasha and McAlester.

THE United States Bureau of Education has recently issued a Union List of Mathematical Periodicals prepared by Professor David Eugene Smith and Dr. Caroline Eustis Seely. This list contains the leading mathematical periodicals needed by research students and to be found in a number of the larger libraries in various parts of the country. Copies may be secured by addressing the United States Commissioner of Education, Washington, D. C.

A HISTORICAL sketch of the observatory of the University of Cincinnati has recently been written by Dr. J. G. Porter, director of the observatory. The Cincinnati Observatory has been in operation since 1843, when it was

established by Professor O. M. Mitchell, professor of astronomy in the old Cincinnati College. Through the generosity of Nicholas Longworth a site for the observatory was secured and telescopes were mounted in 1845. In 1873 the observatory was made the astronomical department of the University of Cincinnati, and the present site on Mt. Lookout was donated by John Kilgour. Professor Mitchell was an innovator, publishing the first American magazine devoted to popular astronomy, and applying the principles now embodied in the chronograph to the recording of time. The scientific achievements of the observatory are well known, among them being the detection of double stars, orbits of comets, prediction of the weather and the study of nebulæ. For years the problem worked on by Dr. Porter and his assistants has been the proper motions of the stars. The few thousands of stars which show sufficient motion to be perceptible, in the interval during which astronomers have had them under observation, have been reobserved at Cincinnati and their motions carefully investigated.

UNIVERSITY AND EDUCATIONAL

NEWS

STONYHURST COLLEGE, Blackburn, England, has planned to raise £20,000 as a war memorial to be devoted chiefly to the erection of new science laboratories.

COLUMBIA UNIVERSITY, at the request of the War Department, is starting an emergency course in engineering for students entering from high schools. This emergency course, embracing civil, electrical, mechanical, metallurgical and chemical engineering, will extend over two years of four quarters each. The first four quarters of the course will be devoted largely to fundamental scientific training in mathematics, physics and chemistry. The strictly engineering subjects will come in the second year. The War Department does not guarantee that any man entering on this course can remain to finish it, but those who do well will be continued in it as long as the needs of the army permit.

LIEUTENANT COLONEL CHARLES F. CRAIG, who until recently has been stationed at Fort Leavenworth, Kans., has been placed in charge of the Yale Army Laboratory School, the new school for bacteriologists and chemists which is to be conducted at Yale University during the period of the war.

DR. R. M. STRONG, professor of anatomy at Vanderbilt University, has been appointed professor and head of the department of anatomy at the Chicago College of Medicine and Surgery.

DR. JOSEPH C. Bock, Chem. Eng. (Vienna), Ph.D. (Cornell), for five years instructor at Cornell University Medical School, has been appointed professor of physiological chemistry in the school of medicine of Marquette University at Milwaukee.

E. J. QUINN, who for the past four years has been a research chemist on the chemistry staff of the Montana Experiment Station has accepted an appointment as assistant professor in the department of chemistry of the State College of Agriculture and Mechanic Arts of the University of Montana. He will have charge of the courses in analytical and agricultural chemistry.

MR. S. H. STROUD, formerly demonstrator in chemistry in the School of Pharmacy, Bloomsbury Square, has been appointed lecturer in pharmacy and chemistry in the University of Sydney, N. S. W.

DISCUSSION AND CORRESPONDENCE

THE FOUNDATIONS OF MECHANICS

IN SCIENCE of August 2, Messrs. Franklin and MacNutt attempt to make it "clearly evident that Professor Huntington's statement (that variation in acceleration from body to body for a given force is logically derivable from the variation from force to force for a given body) is not true." "Logically derivable" is scarcely a clear phrase in this connection. The quid of the matter is found, of course, in the fact that in the table of Messrs. Franklin and McNutt, these authors

have chosen to use three "identifiable" forces. According to their logic, they must mean that their forces are identifiable but not measurable, and further that you can not measure force until you bring in the idea of mass. The distinction between "identifiable" and measurable" seems to me to be valueless. Moreover, mass is in no way necessary either for the identification or measurement of forces. As Perin1 observes. if a stretched spring A balances two stretched springs M+N, then force A force M+N. Messrs. Franklin and McNutt emphasize the fact that mass is independent of time and place and exists independent of any gravitational field. So does the science of mechanics. Messrs. Franklin and McNutt's own logic should, then, force them to the conclusion that for all bodies, where F is measured independently of mass

we have asserted nothing, since no interpretation has been placed on x. y and z. So, in fact, we might go ahead and develop the whole of (mathematical) mechanics without interpreting the symbols at all, or specifying merely that they might be anything consistent with the fundamental equations or postulates and of course with the theorems deduced. Such a body of doctrine is Veblen's2 system of axioms for geometry. The system has no necessary connection with space or geometry at all; but when for the one undefined element, we put "point" the doctrinal function becomes applicable to space. But we could substitute something else and that non spatial-and get an equally good application. So if we let 1 Perrin, "Traité de Chimie physique," Paris,

1903.

2 Transactions of the American Mathematical Society, Vol. 5, p. 343.

where K is the constant of gravitation. These two postulates are obviously both consistent and independent. There is a double definition of mass,-i. e., mass as inertia, and mass as capacity to be attracted in a gravitational field. In the doctrinal function we postulate the m's (whatever they represent, if anything) identical. By experiment we say mass by one definition equals mass by the other. Similarly, a chemical compound is something that (at least) fits into the equations of Gibbs' paper "On the Equilibrium of Heteoogeneous Substances." It is intended, of course merely to indicate a line of thought, not to develop it.

Thus it is clear that the units we have in the Bureau of Standards need not be the same as the undefined elements in the doctrinal function. We do not need even to imagine that Bureau keeping standard springs, rubber bands, strong armed men, etc., and more than it would have to keep a standard point (!) instead of a standard meter, for Veblen's system of geometry. Any equation may be made use of to measure any quantity which it contains.

There remains the formal possibility that we might find by experiment that the mass of (1) is not the same as the mass of (3). A doctrinal function corresponding to mechanics would not be affected, but a new one would have to be made corresponding to the new experimental fact, provided we wished to define mass, in part, by making use of gravitational pull, that is, to retain a postulate comparable to (3) along with (1). But this last is not necessary, since f/am is a sufficient definition of mass, and has nothing to do with

gravitation that we can explain further. It is the real definition of mass, and (3) is a useful additional postulate, or a useful experimental fact.

So far as ease of thinking is concerned, which is more or less irrelevant, force and acceleration are far more easily grasped than mass. That is to say, it appears so to the writer; but Frederic Soddy says: "the conception of force and its pseudo physical reality undoubtedly delayed for centuries the recognition of the law of the conservation of energy. Only what is conserved has the right to be considered a physical existence. In other branches of science, the conception is a stumbling block and a delusion." Perrin takes a radically different view. There seems to be a certain mysticism in Soddy's contention, for what do we care whether a force goes on "existing" when we finish with it? We find velocities and temperatures convenient, yet they go out of "existence" without any special regret. The main fact is we can give numbers to these forces, temperatures, etc., and make equations that correspond (somewhat) to experiments.

Mass, on the other hand, means (1) inertia. (2) capacity to be attracted by a gravitational field (3) capacity to create a gravitational field, and some other things. It appears to depend on velocity, though it is not intended to consider non-Newtonian mechanics. It is about as puzzling a thing as there is in physics. -for who knows what gravitation is?

QUOTATIONS

SCIENTIFIC WORK IN INDIA

THE Board of Scientific Advice for India has, like similar bodies elsewhere, felt the effect of war conditions. The board has been strengthened by the addition of a representative of the Indian Munitions Board, and power has been conferred upon the president to appoint subcommittees, membership of which need not be confinel to members of the board, for the purpose of dealing with particular investigations. The board has found it necessary to modify the treatment of programs of work submitted by individual scientific departments, and to resolve that the annual report for 1916-17 be confined to a brief statement of work actually done during the year, also that the bibliography of publications bearing on particular subjects be consolidated. But the establishment of a Zoological Survey recorded for the year under notice, has not affected the composition of the Board of Scientific Advice, representation of this subject having been provided for already. That its organization should have been so

slightly affected affords striking evidence of the soundness of the original constitution of the board.

The report of the board for 1916-17 is an interesting document, and much of its contents, especially where the applications of science are concerned, may repay perusal outside India. In agriculture the low values of