Naples on his way to Mexico to study recent earthquakes there for his government.

FREDERIC H. LAHEE, formerly professor of geology at the Massachusetts Institute of Technology, and since the latter part of 1918 associate geologist for the Sun Oil Co., of Dallas, Tex., will take charge of the geological department of the Twin State Oil Co., at Tulsa, Okla., while still maintaining his connection with the Sun Co.

MR. ROLLIN C. DEAN, who for the last eight years has represented the Bausch and Lomb Optical Co. among the universities and colleges of the east, will become connected with The Rockefeller Foundation.

DR. MARY J. ERICKSON has arrived at the University of Iowa to take charge of the research work in the state board of health under the recent appropriation from the federal government for investigation in the field of venereal diseases.

PROFESSOR C. E. SEASHORE, of the psychology department of the State University of Iowa, lectured on the "Psychology of Musical Talent" at the University of Kansas on March 1.

DR. CHRISTINE LADD-FRANKLIN lectured recently before the Research Club of the Harvard Medical School on the theory of color sensation.

PROFESSOR EDWARD J. MOORE, of the department of physics of the University of Buffalo, spoke before the Buffalo Society of Natural Sciences on February 3, on "The Einstein Gravitation Theory."

PROFESSOR DOUGLAS W. JOHNSON, of Columbia University, addressed the faculty and students of Mount Holyoke College on February 18, on "The Work of the Geographer and the Geologist in the War."

DR. W. H. R. RIVERS, of the University of Cambridge, will lecture on "Ethnology: its Aims and Needs" at Columbia University on the evening of March 15. It will be a general meeting of the New York Academy of Sciences arranged by the Section of Anthropology and Psychology and the American Ethnological Society.

HERBERT RALPH WERNER, assistant professor of zoology in the Iowa State College, died on February 14, at the age of thirty-one years, of pneumonia following influenza.

DR. CHARLES GORDON HEWITT, Dominion entomologist and consulting zoologist, died at Ottawa on March 1. He had resided in Canada since 1909, having been born in Scotland in 1886.

SIR THOMAS ANDERSON STUART, professor of physiology and dean of the faculty of medicine in the University of Sydney, died on April 3. He was born in Scotland in 1856. THE U. S. Civil Service Commission anan examination for assistant fuel engineer. A vacancy in the Bureau of Mines, Department of Interior, at Pittsburgh, Pa., at $4,200 a year, will be filled from this examination.

nounces

HOUSE tariff measures fixing duties on optical glass, laboratory apparatus, surgical instruments and glass and porcelain articles for laboratory use have been ordered favorably reported by the Senate Finance Committee.

THROUGH the courtesy of the American Geographical Society the spring meeting of the Association of American Geographers will be reinaugurated this year. The meeting will be held in New York City at the American Geographical Society's hall, April 16 and 17, 1920. All interested are most cordially invited to attend.

THE Iowa Academy of Science will hold its thirty-fourth annual meeting at the University of Iowa on April 30 and May 1, under the presidency of Professor T. C. Stephens, of Morningside College. It is expected that fully one hundred papers on scientific subjects will be presented.

THE next annual meeting of the British Medical Association will be held in the University of Cambridge at the end of June under the presidency of Sir Clifford Allbutt. It was intended to hold the 1915 meeting at Cambridge under his presidency, but the war intervened and he has remained president of the association.

YALE UNIVERSITY has recently received from Bayard Dominick, of the class of 1894, Yale College, gifts amounting to $40,000 for scientific exploration in the Southern Pacific Ocean. Professor Herbert E. Gregory, of Yale, is the active head of the expedition, and the funds will be disbursed by the Bishop Museum of Honolulu. It is expected that the work of the expedition will extend over a period of two years and that it will be carried on by a group of distinguished men of science. Professor Gregory has been granted leave of absence for the balance of the year by Yale and is now in Honolulu.

A NEW Museum has been opened at Yellowstone Park, Wyoming, for the preservation and exhibition of natural history specimens of the region.

THE fortieth annual report of the United States Geological Survey, made public, compares the present scope of the work with that of the work done during the first year of this organization. The growth of the survey is suggested by a comparison of the appropriations for the present year, which comprise items amounting to $1,437,745, with the total appropriation of $106,000 for the first year, 1879-80. During the 40 years the number of employees has been increased from 39 to 967.

THE arrangements for the amalgamation of the four existing British meteorological services are practically completed, and it is expected that at an early date the reorganization, which will combine the Meteorological Office with the weather services of the Air Ministry, the Navy, and the Royal Engineers, will be effected under the Department of the Controller-General of Civil Aviation, and will be directed by Sir Napier-Shaw, the present Director of the Meteorological Office at South Kensington. The headquarters of the amalgamated services will be at the Air Ministry, Canada House, Kingsway. It is understood that the forecasting department and other departments of the Meteorological Office will be transferred from South Kensington to the Air Ministry, while the statistical department and the library will remain at the present

office in Exhibition Road. The British Rainfall Association, which was founded in 1860, and which has been a very successful private enterprise, will come under the director of the Meteorological Office, but it is expected that its special work will continue to be carried on at Camden-square. The combined services will be in close touch with all the colonial and foreign observatories and the Air Minister will assume Parliamentary responsibility for the new combined department.

THE Advisory Committee at the American Chemical Society, on recommendation of Editor E. J. Crane, has passed the following vote:

That Chemical Abstracts be empowered to loan to members in good standing of the American Chemical Society, copies of current publications upon request; that each such request must be accompanied by twenty-five (25) cents for each issue requested to cover cost of packing, mailing and correspondence, and must further be accompanied by an undertaking on the part of the requesting member to replace such issue or issues, should they not be returned to Chemical Abstracts in good order, less reasonable wear and tear; Chemical Abstracts to notify the loaning member of receipt in good or bad order, as the case may be, of the loaned issue and then to close the transaction accordingly.

THE Oberlin College Research Committee, affiliated with the National Research Council, met recently for dinner and the transaction of business at the Faculty Club. The present committee consists of men engaged in experimental scientific work, but a recommendation was adopted to include those from the mathematics department. Discussion centered around possible methods of stimulating and financing research in those departments which care to do such work, and also the development of research spirit as a definite college policy. It was definitely expressed as the opinion of those present that a college of the standing of Oberlin must abandon the policy that teaching is the sole business of the faculty members, and that productive work must be given the prominence it merits. THE United States Committee on the Ramsay Memorial Fund has transmitted

£3,500 which it has collected; £263 have been sent direct by contributors; approximately £100 yet remain in the hands of the treasurer, Mr. W. J. Matheson. Professor Baskerville, the chairman, hopes that the total American contribution which is £3,863, may be raised to £4,000, and that the American subscriptions may then be closed. The total fund now amounts to £51,274. Professor H. Kamerlingh Onnes reports contributions of £1,571 given or promised by donors in Holland.

ROBERT W. LAWSON writes to Nature from the Physics Laboratory, the University of Sheffield, quoting a letter of Professor Einstein as follows: "Zwei junge Physiker in Bonn haben nun die Rot-Verschiebung der Spektral-Linien bei der Sonne so gut wie sicher nachgewiesen und die Gründe des bisherigen Misslingens aufgeklärt."

MR. THEODORE W. ROBINSON, of Chicago, has given $500 to be used in purchasing museum material for the Oriental Institute of the University of Chicago; and a donor whose name is withheld gives $25,000 for the same purposes. These funds will be used by Professor James Henry Breasted, who is now in Egypt on his way to Mesopotamia.

THE National Research Council has received a gift from the Southern Pine Association of $10,000 to pay for the incidental expenses of a coordinated scientific study by a number of investigators of the re-growth of trees or cut-over forest lands with the aim of determining the best forestry methods for obtaining the highest productivity. The investigation will be conducted under the advice of the Research Council's special committee on forestry and will not duplicate any present government or other undertakings along similar lines.

On the invitation of the council of the senate of the University of Cambridge, the chancellor, the vice-chancellor, Mr. Rawlinson, Professor Sir Joseph Larmor, Professor Sir J. J. Thomson (master of Trinity), Dr. Hobson, and Professor Sir Ernest Rutherford, have consented to serve as representatives of the university on a joint committee of the Royal So

ciety and university for the purpose of taking steps to secure an appropriate memorial to the late Lord Rayleigh.

UNIVERSITY AND EDUCATIONAL
NEWS

PROFESSOR WILLIAM H. WALKER, chairman of the administrative committee of the Massachusetts Institute of Technology, since the death of President Maclaurin, has resigned to devote his time to the division of industrial cooperation and research. The new chairman is Professor H. P. Talbot, chairman of the faculty. Professor E. B. Wilson, of the physics department has been appointed a member of the committee, on which is also Professor Edward Miller, of the department of mechanical engineering. Professor Walker is succeeded as head of the course of chemical

engineering by Professor Warren K. Lewis. As has been already noted here, Professor Arthur A. Noyes, head of the research department, has handed in his resignation as of January 1, to go to the California Institute of Technology.

AFTER thirteen years of service as professor of medicine and ten years as dean of the Yale School of Medicine, Dr. George Blumer has resigned to resume consultation practise, but he will not wholly sever his connection with the school and the hospital.

DR. ARTHUR B. LAMB has been promoted to a professorship of chemistry at Harvard University.

DR. ADOLPH KNOPF, of the U. S. Geological Survey, has been appointed lecturer in geology in Yale University for the second term of the present academic year. He has in charge the undergraduate and graduate courses in petrology formerly taught by the late Professor Pirsson. Additional appointments in the geological department are those of Dr. Carl O. Dunbar (B.A. Kansas 1913, Ph.D. Yale 1917) as assistant professor of historical geology, and Mr. Chester R. Longwell (B.A. Missouri 1915, M.A. 1916) as assistant professor of geology.

THE trustees of Cooper Union, New York City, have authorized the organization of a four-year day course in industrial chemistry to be started in September of the present year. This course will aim to train men as analysts, research chemists, foremen and superintendents in manufacturing plants, and sales agents. Mr. Maximilian Toch, has been appointed adjunct professor of industrial chemistry.

DR. H. E. ROAF has been appointed to the university chair of physiology tenable at the London Hospital Medical College, and Professor T. Swale Vincent to the university chair of physiology tenable at the Middlesex Hospital Medical School.

DISCUSSION AND CORRESPONDENCE

AN ODD PROBLEM IN MECHANICS

TO THE EDITOR OF SCIENCE: The following statements are intended to throw light on the questions raised by Dr. Hering in his letter entitled "An odd problem in mechanics" in SCIENCE for January 9, 1920.

The statements in the second paragraph of the letter are correct: a body travelling eastward on the ground along the equator will exert less pressure on the ground than one at rest relative to the earth's surface, and still less pressure than a body travelling westward. The correctness of this statement was verified experimentally in connection with observations to determine the intensity of gravity at sea by determinations of the boiling point compared with readings of the mercury barometer. In the spring of 1909 the Russian government placed a war ship at the disposal of Professor Hecker, who was engaged in this work, and tests were made in the Black Sea by comparing the gravity obtained when the ship was running east with gravity at the same point when the ship was running west. The correction in question is of the order of 0.100 dyne for a vessel of fair speed, and the reality of the expected effect and the necessity of applying a correction for it were, of course, verified. It should be mentioned that the rolling, pitching and lifting of the ship, which occur on all courses, were such

that the total effect of the ship's motion did not necessarily reverse in sign when the ship's course was reversed.

In the third paragraph it is assumed that the "gyroscopic tendency (of a rotating horizontal flywheel) to get into the vertical plane has been counteracted and may be neglected." But the forces Dr. Hering has been describing in this paragraph are exactly the gyroscopic forces themselves that tend to make the axis of the flywheel parallel to the earth's axis. At the equator, since the celestial pole is in horizon, the plane of the flywheel would tend to become vertical. If the gyroscopic tendency is counteracted, there is, of course, no shifting of the axis of rotation.

In the cases supposed in the fourth paragraph, there are gyroscopic forces arising from the earth's rotation that Dr. Hering has not considered. When the plane of rotation is north and south, that side of the disk which is descending will tend to move eastward, and the side that is ascending will tend to move westward, thus tending to turn the plane of the disk out of the meridian into the prime vertical, so that its axis shall be parallel to the axis of the earth. The apparatus will therefore not be dynamically balanced as Dr. Hering states. At the equator there is no twisting effect due to the horizontal motion of the particles on the edge of the disk, for this effect varies as the sine of the latitude. At the equator, when the plane of the disk is east and west, its axis is parallel to the earth's axis, and the apparatus is dynamically balanced.

The nature of the general question raised may be stated in a few words as follows. For a body at rest on the earth, it is sufficient to consider only the attraction of the earth and the centrifugal force due to the earth's rotation. For a body in motion relative to the earth, there are additional apparent forces to be considered, the so-called gyroscopic forces, or compound centrifugal forces. These apparent forces arise from the fact that our axes of reference are not fixed in direction in space, but are rotating. These forces are all proportional to the product of the earth's angular velocity of rotation by a component velocity