June 2. "Vacant-lot Gardening," by Mr. Carl Bannwart.

June 9. "Garden Roses," by Professor A. C. Beal.

(Exhibition of Roses and Peonies, June 9 and 10.) June 16. "The Seaweeds of New York and Vicinity," by Dr. M. A. Howe.

June 23. "Lillies for Everybody," by Mr. Arthur Herrington.

June 30. "The Food Value of Wild Mushrooms," by Dr. W. A. Murrill.

WE learn from the Fisheries Service Bulletin that in the early part of September the Fish Hawk made another cruise in Chesapeake Bay for the purpose of ascertaining the abundance and quality of the hydroid, or sea moss," material available at this season. A Baltimore manufacturer of sea-moss articles accompanied the vessel. While the growth is not of the best quality at this season, abundant supplies were obtained, and the manufacturer expressed himself as well satisfied with the opportunity for a commercial fishery. On the conclusion of this trip the eighth regular cruise of the Chesapeake Bay investigation was completed. During the latter part of August the schooner Grampus left Norfolk, Va., to continue investigations in Atlantic coast waters, in charge of W. W. Welsh. A line of hydrographic stations was first made from Cape Henry to the gulf stream. About twenty miles southeast by east from Cape Henry a good haul of croakers was made with a small otter trawl, suggesting the possible use of this type of net for the capture of this species. Samples of sargassum weed were obtained for analysis in regard to the possible use of this material as a source of potash, and possibly of iodine and bromine. The vessel then proceeded to Cape May, N. J., and an examination was made of the pound nets in the vicinity of Five Fathom Bank. Observations were continued between Cape May and Gloucester, Mass. At the latter point a shortage of seamen made it necessary to tie up the vessel, and the work that had been planned for the Gulf of Maine was, therefore, abandoned.

UNIVERSITY AND EDUCATIONAL
NEWS

PLANS are now being prepared for a new chemistry building at the Montana State Col

lege to replace the one burned down last October.

FIVE departments of fellowships in mining and metallurgical research, each valued at $720 for a year of twelve months, are offered by the College of Mines of the University of Washington in cooperation with the federal Bureau of Mines.

DR. EDWARD M. FREEMAN, assistant dean of the department of agriculture of the University of Minnesota, has been offered the deanship of the college of agriculture of the University of Arizona, at Tucson.

THE following instructors at Wellesley College have been advanced to assistant professorships: Mabel A. Stone, botany; Helen S. French, chemistry, and Sarah R. Davis, hygiene.

DR. HOWARD PARSHLEY, who has been working at the Bussey Institution, Harvard University, has been appointed assistant professor of zoology at Smith College.

FRED T. ROGERS, Ph.D., assistant professor

of physiology in Baylor University, Waco,

Texas, has been appointed to an instructorship in physiology at the University of Chicago.

J. F. REILLY has been promoted to an associate professorship of mathematics at the State University of Iowa.

VICTOR E. RECTOR, principal of the Antioch Industrial School near Hartsville, S. C., and a member of the House of Representatives, has been elected professor of agriculture at the University of South Carolina.

DISCUSSION AND CORRESPONDENCE THE VARIETAL RELATIONS OF CROWN GALL

THE disease known as crown gall and hairy root has been the subject of much experimental inquiry. It has long been known that there were several forms of this disease appearing on apple trees and for some time it was a question whether these several forms were due to the same causal organism. There have been recognized a hard and a soft form of crown gall and the simple, woolly knot, broom root and aerial forms of hairy root.1

1 Hedgecock, Bureau of Plant Industry, Bulletin 186.

The writer has during the past few years propagated several thousand apple trees of many different varieties on their own roots by means of the common whip graft, but cutting off the seedling nurse root after two seasons' growth and replanting those trees which had thrown out roots from the scion, thus establishing the variety on its own roots. Many of these trees have been more or less troubled with the crown gall and hairy root. It has been observed that there is a tendency for a given variety to have only a single form of the disease. Thus the Jewett apple shows usually if not always the hard form of the gall, the Red Astrachan the simple form of the hairy root and the Oldenburg the woolly knot form with many soft fleshy root growths. Other varieties show the broom root form and still others often the aerial form.

In the ordinary method of propagation of apple trees the root systems are of seedling origin and from a pomological viewpoint the root system of every tree is a different variety. May not this be the reason for the various forms of crown gall and hairy root?

Some varieties on their own roots seem to be largely if not entirely immune to this disease. If this proves to be really the case, here may lie the solution of the problem of the prevention of crown gall. If a resistant variety is selected as the root variety, and the variety desired propagated on it, trees immune to the disease may presumably be secured. Probably the economic advantage would warrant the extra effort necessary to propagate such trees, only under conditions where the crown gall was especially troublesome.

There are other root diseases which are injurious, especially through the southern part of the apple belt, that might possibly be avoided in a similar fashion.

J. K. SHAW MASSACHUSETTS EXPERIMENT STATION

WHEN A FORCE IS A FORCE

REFERRING to the perennial discussion of the meaning of force and of the law of action and reaction, lately revived in the pages of SCI

ENCE,1 I venture to suggest that the essential point of the alleged difficulties which have been raised is covered by the following simple propositions:

1. A force is a push or a pull exerted upon a body (portion of matter) by another body.

2. Whenever a body A pushes or pulls a body B, then at the same time B pushes or pulls A equally in the opposite direction. Such a pair of forces is an action and reaction." An action-reaction pair concerns two bodies and only two.

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3. The two forces of an action-reaction pair never balance each other; a force acting on A can not balance a force acting on B.

4. To balance a force acting on B, another force must be applied to B.

One who keeps these simple facts in mind will, I believe, find it easy to decide whether an alleged force is really a force in the meaning of the Newtonian laws. He will also see that there is no contradiction between the statement that forces always occur in actionreaction pairs and the statement that forces are often unbalanced. L. M. HOSKINS STANFORD UNIVERSITY, March 22, 1917

SCIENTIFIC BOOKS

The Potato. By ARTHUR W. GILBERT, assisted by MORTIER F. BARRUS and DANIEL DEAN. New York, The Macmillan Co., 1917. Pp. i-xii and 1-318, Pl. XVI.

The author states in his preface that the book is intended to give brief and practical suggestions on the growing, breeding and marketing of potatoes, and the subject-matter amply substantiates the statement. This publication, in addition to being up-to-date in its cultural directions, devotes considerably more attention to the subject of potato breeding than any of our preceding American treatises on the potato. Conveniently arranged statistical data are presented in Chapter I. under the caption of Acreage, Distribution, Production and Valuation. Chapter III. em

1 See articles by Gordon S. Fulcher (November 24, 1916), and Andrew H. Patterson (March 16, 1917). Mr. Fulcher's discussion seems to me to be entirely sound.

The three chapters devoted to "Climate, Soils and Rotations," "Manures and Fertilizers," and "Planting," are excellently treated, the suggestions being clear, concise and practical. In the opinion of the writer, the value of the subject-matter in these chapters would have been enhanced by a few wellselected illustrations of potato implements and cultural methods. The discussion of potato diseases and their control is clear and convincing and should prove very helpful to both the farmer and the student. A chapter on "Markets, Marketing and Storage" is both suggestive and helpful, as is also that on the cost of growing potatoes.

As a whole, the book is unique, in that it is strikingly devoid of illustrations, as compared with most of the recently published agricultural text-books. It is a welcome addition to our present text-books on the potato, and should find a place in the classroom of agricultural schools and colleges.

WM. STUART

Health and Disease: Their Determining Factors. By ROGER L. LEE. Little Brown, Co., 1917. $1.75.

This book gives a very pleasing presentation of the factors of health and disease in strictly non-technical language. The author has successfully and very commendably avoided a consideration of the treatment of ailments, and has emphasized throughout the preventive measures which may be performed, or encouraged by the cooperation of the layman. The most reprehensible thing in the book, from the reviewer's view-point, is the title of Chapter XII., "The Air-borne Diseases!" After the struggle that has been, and is being made to disillusion the popular mind of the idea that air is an important conveyor of disease, it is a misfortune to use this phrase in any sense.

The author goes to some pains to explain that he includes under this term chiefly "droplet " or mouth-spray infection, but the use of "airborne" throughout the book is bound to nourish the age-old fallacy.

The first nine chapters consider chiefly matters of personal hygiene, the next nine, communicable diseases, and the last six, matters of general sanitation. The sequence and point-ofview throughout are good. Specially to be commended are the chapters on Alcohol, Tobacco and the Habit-forming Drugs and on the Venereal Diseases and Sex Hygiene.

There are a good many minor criticisms which might be made, as, for example, the loose use of the term antitoxin on page 173, speaking of the "Spirochata pallida" instead of Treponema pallida, the sentence "Red flap' is caused by a ringworm which is really a vegetable bacterium" (p. 243), and the statement that "tubercle bacilli are only present in milk when there is tuberculous disease of the udder " (p. 306).

The book contains 378 pages, is printed on rough paper in good print and is amply indexed. There are no cuts or diagrams in the book and no specific references are given. It is to be most cordially recommended to the lay reader and might find a useful place as a text in a general elementary college course in hygiene and sanitation, and should certainly be on the desk of every teacher of biology and hygiene. CURTIS M. HILLIARD

SIMMONS COLLEGE

SPECIAL ARTICLES

A NOTE ON THE EFFECT OF ASPHYXIA AND AFFERENT STIMULATION ON ADRENAL SECRETION

RECENT observers have expressed some doubt as to the effect of asphyxia and afferent stimulation on the secretion of the adrenal glands. Under the circumstances it is desirable to have simple methods which any one may use to demonstrate the effect. During the past few months, with the aid of Mr. H. F. Pierce, I have devised such methods.

If both carotid arteries, both subclavian arteries and the aorta just anterior to the inferior mesenteric artery are tied, and the

nerves accompanying the cœliac axis and the superior and inferior mesenteric arteries are then carefully severed, a rise of blood pressure taken from the carotid must be mainly due to contraction of the splanchnic area which is now denervated. If a vigorous cat is operated upon in this way under light urethane anesthesia, asphyxia for one minute will result usually in a rise of blood pressure at the end of forty seconds and a very considerably greater rise as soon as respiration begins again. These results do not occur if the adrenal glands are removed. If these glands are left in the body, but disconnected from the central nervous system, a rise of pressure may still be produced if the asphyxia is continued for a considerably longer period than is required when the splanchnic nerves are intact.

If the heart is completely denervated by severing both vagi in the neck and removing both stellate ganglia, it becomes a very delicate indicator of increased adrenin in the blood. Stimulation of the central end of the cut sciatic nerve (in a cat under urethane) will then cause the heart rate to increase, in some instances 50 beats a minute. The phenomenon does not occur if the adrenal glands are removed or if the splanchnic nerves are cut. The method is advantageous in that it shows the latent period and the duration of the secretion. The effect on the heart of asphyxia is not so great as the effect of afferent stimulation, in all probability because of the antagonism between the influence of carbon dioxide and of adrenin.

A great deal of care must be taken in operating on the abdominal cavity to avoid manipulation. As was shown many years ago, such operations produce changes which can be best accounted for by continuous discharge of the nerve impulses along splanchnic courses. Thus the adrenal glands would be persistently stimulated. A potent source of error in previous work, in which the abdominal cavity has been opened, has doubtless been the failure to exercise extreme care to avoid rough manipulation.

A full account of this investigation will be

published in the American Journal of Physiology. W. B. CANNON

SOCIETIES AND ACADEMIES THE BIOLOGICAL SOCIETY OF WASHINGTON THE 567th regular meeting of the society was held in the assembly hall of the Cosmos Club, Saturday, March 10, 1917, called to order by President Hay at 8 P.M., with 45 persons in attendance.

On recommendation of the council Mrs. L. 0. Howard and Dr. Martha Brewer Lyon were elected to active membership.

Under the heading book notices, brief notes, etc., Dr. H. M. Smith exhibited a manuscript and handillustrated book dealing with beetles. It was about 60 years old. Dr. Smith presented it to Dr. L. O. Howard. Professor W. P. Hay presented some notes on the flying squirrels of this vicinity with observations on their habits and behavior as pets. Dr. H. E. Ames called attention to a newspaper clipping recording the flight of two tagged ducks a distance of 2,000 miles in about 60 hours. He sought verification of the statement.

The regular program consisted of two communications:

Precipitins: M. W. LYON, JR.

Dr. Lyon described an anti-beef serum he had lately prepared, and set up a series of test tubes containing dilutions of beef, sheep, hog and human serums, and demonstrated the action of the antibeef serum on these, viz., specific precipitation when added to the diluted beef serum, group precipitation with diluted sheep serum, and the nonprecipitation with diluted hog and human serums. He mentioned briefly the history and theory of precipitating serums and explained their use in identifying suspected animal proteins and in showing the blood relations of various animals. In discussing this communication A. H. Jennings explained how he had made use of the precipitin reaction in determining the kinds of animals bitten by biting flies. Dr. George W. Field and H. F. Taylor also took part in the discussion. Porpoises and Steamers: WILLIAM PALMER.

Mr. Palmer commented on the frequency with which porpoises are found about the bows of steamers and advanced explanations as to their presence there and methods of progression. His communication was illustrated by diagrams and lantern views of porpoises and other cetaceans. It was discussed by Dr. H. E. Ames.

M. W. LYON, JR., Recording Secretary

FRIDAY, MAY 18, 1917

CONTENTS

465

474

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THE PROVISION MADE BY MATHE

MATICS FOR THE NEEDS

OF SCIENCE1

MATHEMATICS beyond the merest elements has been regarded by some as an excrescent malady of the human spirit, generated like the pearl in an abnormal and morbid way and representing a non-living embedment in the active tissue of the organism of society; by others it has been supposed to exhibit the highest intellectual reach of mankind, being in itself the most 476 powerful tool yet devised for the interpretation of natural phenomena, while at the same time it affords a satisfying expression of the furthermost esthetic attainment. On the one hand, it is considered a piece of jugglery in which it is the joy of the proficient to produce more and more complicated entanglements to astonish the beholder and overwhelm him with the sense of mystery; on the other hand, it is seen to be the systematic unfolding of remarkable and important properties of a highly fascinating creation or construction of the human spirit by means of which it has at once its most intellectual delight and the best means of understanding its environment. Some workers seem to resent the interference of mathematics with their comfort in the conclusions of descriptive science and its demands that observation shall be reduced to measurable elements and the laws of nature be expressed in mathematical formulas; other thinkers believe that natural science is real science only in so far as it is mathematical, that it is only through mathematics that true science can 1 An address delivered before the Illinois Chapter of Sigma Xi on January 17, 1917.

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Societies and Academies:

The American Mathematical Society: PROFESSOR F. N. COLE

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