and of the influence that the distribution of rainfall and temperature in various parts of the country has on the character of the crop.

Then the cross-breeder's work begins: acclimatization alone is hardly likely to yield the ideal plant, but by it are found plants possessing the features, one here and one there, that are desiderated; and starting with this ground material the hybridizer can eventually turn out an individual possessing to a large measure all the qualities that are sought for.

There is little hope that science can do anything wholly new for agriculture; acclimatization, breeding and selection have been the mainstay of farming progress since the beginning of time, just as the action of the nitrifying bacteria and of nitrogen fixation by the leguminous plants was instinctively apprehended by the earliest farmers of whom we have any record.

But with increasing knowledge comes more power, and particularly the possibility of accelerating the rate of progress; agricultural improvements in the past have resulted from the gradual and unorganized accretions of the observation and experience of many men, often of many generations, now that we are provided by science with guiding hypotheses and by the organization of experiment with the means of replacing casual opinions by exact knowledge.

Even the properties of the soil and the character of our farm crops and animals-stubborn facts as they are and deeply grounded in the nature of things-ought to become increasingly plastic in our hands. A. D. HALL.

SCIENTIFIC BOOKS. Physiological Economy in Nutrition. By RUSSELL H. CHITTENDEN, Ph.D., LL.D., Sc.D. New York, F. A. Stokes Co. 1904. This notable volume, the production of Professor Chittenden and his coworkers, of whom Professor Lafayette B. Mendel is the

most prominent, finally dispels the tradition that a continued liberal allowance of proteid in a normal diet is a prerequisite for the maintenance of bodily vigor.

Professor Chittenden had suffered from persistent rheumatism of the knee joint and determined on a course of dieting which should largely reduce the proteid and calorific intake. The rheumatism disappeared and minor troubles such as 'sick-headaches' and bilious attacks no longer recurred periodically as before.

There was a greater appreciation of such food as was eaten: a keener appetite, and more acute taste seemed to be developed and a more thorough liking for simple foods.

During the first eight months of the dieting there was a loss of body weight equal to eight kilograms. Thereafter for nine months the body weight remained stationary.

Two months of the time were spent at an inland fishing resort, and during a part of this time a guide was dispensed with and the boat rowed by the writer frequently six to ten miles in a forenoon, sometimes against head winds (without breakfast) and with much greater freedom from fatigue and muscular soreness than in previous years on a fuller dietary.

During this latter period of nine months the nitrogen of the urine was determined daily. The average was 5.69 grams. During the last two months this was reduced to 5.40 grams. Experiments showed that about one gram of nitrogen was eliminated in the fæces, and that nitrogen equilibrium could be maintained with dietaries of low calorific value (1,613 and 1,549 calories) containing 6.40 and 5.86 grams of nitrogen. These figures correspond to diets containing 40 and 36.6 grams of proteid instead of 118 grams commended by Voit and honored by habit and tradition. The foods with the strongest flavors are meats.

Professor Chittenden believes that the large quantity of proteid in the ordinary diet is due to self-indulgence. He protests against such indulgence and believes that a futile strain is thereby placed upon the liver, kidneys and other organs concerned in the transformation and elimination of the end products of proteid metabolism.

These experiments, however, were not confined to an individual or even to a single group of individuals. Similar experiments were made on other professional men, on student athletes in training, and on soldiers under military regimen. The nitrogen in the urine was determined daily in twenty-six individuals for periods extending from five to nine months.

Summarizing the results obtained in all these groups of individuals, it is established that a diet containing about fifty grams of proteid (8 grams of nitrogen) is able to maintain the adult body machine in perfect repair. The professional group alleged a greater keenness for its work, the athletic group won championships in games, and the soldiers maintained perfect health and strength, many professing repugnance to meat when allowed it after five months of practical abstinence.

Although it is possible that the alleged improved mental condition may have been due to mental suggestion, still the fact remains that it has been absolutely proven by Chittenden's work that the allowance of proteid necessary for continued health and strength may be reduced for many months to one half or less what the habit of appetite suggests.

The reviewer would, however, remark that it still remains to be proven that the fifty grams of proteid in the diet-which is not greater than the body would metabolize in starvation-is advisable as a program for the whole of one's adult life. It may also be that more than this quantity is indicated, during convalescence from wasting disease, or during the muscular hypertrophy which accompanies preliminary training for muscular effort.

The reviewer believes that Professor Chittenden has fallen into error in the commendation of 2,500 to 2,600 calories as an ample energy content for the diet of a soldier at drill.

Accurate information on this point is only obtainable through respiration experiments. Chittenden, pursuing a sedentary life, prescribes 2,000 calories for himself or 35 calories per kilogram of body weight, while Mendel requires 2,448 calories or 35.3 calories per kilogram. These are entirely normal values for people at light work. In the earliest

calculations of Voit in 1866 it was shown that a man of 70 kilograms on a medium mixed diet produced 2,400 calories, or 34.3 calories per kilogram. Rubner allows 2,445 calories to men of 70 kilograms weight engaged in occupations involving light muscular work, men such as writers, draughtsmen, tailors, physicians, etc.

But the soldiers under Chittenden exercised for two hours in the gymnasium, then apparently drilled for one hour, and walked for another hour. This physical work can only be accomplished at the expense of increased metabolism. Zuntz has shown that to walk 2.7 miles in one hour along a level road requires an extra metabolism equivalent to the liberation of 159.2 calories in a well-trained man weighing 70 kilograms. If a soldier during four hours of exercise actually accomplished the equivalent of work of a walk of ten miles over and above what Professor Mendel accomplished in his laboratory, then the metabolism of the soldier would be larger than Professor Mendel's by 637 calories (159.2 X 4) or he would have had a total metabolism of 3,085 calories (2,448 +637). This does not seem an improbable amount.

For ordinary laborers working eight to ten hours a day, such as mechanics, porters, joiners, soldiers in garrison and farmers, 3,000 calories, as advocated by Voit, is apparently not too great. Rubner's diet for the same class calls for 2,868 calories. Chittenden's allowance of 2,500-2,600 seems to the writer too small, while Atwater's of 3,400 appears excessive.

Unstinted praise for painstaking endeavor and unremitting toil belongs to the workers who have achieved this volume. It is a monument of fidelity and an inspiration to thoroughness in scientific work.

GRAHAM LUSK. UNIVERSITY AND BELLEVUE HOSPITAL MEDICAL COLLEGE.

The Insulation of Electric Machines. TURNER and HOBART. Pp. vi+297. 146 illustrations. New York, The Macmillan Company. 1905. Price, $4.50.

It is a difficult and tedious task to write a

book upon a subject which is in the empirical stage of its history, yet in this volume the authors have succeeded in producing a work which is rich in useful information, and which the electric constructor will find a valuable addition to his library. From a scientific standpoint perhaps the most interesting portion of the book is the second chapter, which summarizes very effectively the present state of knowledge regarding the dielectric strength of various materials under various conditions. Nothing is more convincing evidence of the need of further investigating the passage of electricity through gases than the discordant values obtained by different experimenters for the dielectric strength of air.

The constructor will find the chapters on field and on armature insulation and on the 'space factor' exceedingly practical and suggestive, and indeed wherever the authors have had the opportunity of drawing upon their own valuable experience and exercising untrammeled their nice discrimination the results are very satisfactory. Unhappily, insulation at present must rank as crude art rather than as science, and art, too, somewhat luridly colored by commercial daubers.

Of patented insulating preparations and secret compounds the name is legion, and good, bad and indifferent, all alike make the most extravagant claims, and back them up by experiments. These compounds can not be left without mention in a book on insulation, for some of them are highly meritorious, but proper and adequate treatment of them is a practical impossibility. In dealing with this part of their subject therefore, the authors can hardly do more than supplement the alleged facts by such data as are available and to let the matter go at that. They have at least avoided the error of assuming commercial data to be altogether reliable by giving several points of view on disputed topics. The chapters treating of oil insulation fortunately escape such difficulties, paraffin and other oils. being free from patents and trade marks, and these will well repay study.

The facility with which oils, spite of the old saying that oil and water will not mix, take up moisture enough to ruin their insulating prop

Grundriss der Soziologie. By LUDWIG GUMPLOWICZ. Second edition, revised and enlarged. Vienna, 1905.

Sociologists in this country will be interested in this new edition of Doctor Gumplowicz's famous work. In the preface he calls attention to the rapid development of sociological study during the last twenty years, in which development he modestly hints that his 'Grundriss' might well assert, Quorum pars magna fui.

The text of the first edition is preserved intact, with slight verbal changes here and there. The chief modifications consist in additions, reference notes and quotations from later works. In book one, for instance, the history of sociology is brought down to date. Special attention is given in this to the views of Ratzenhofer, whose untimely death while homeward bound from the congress at St. Louis, deprived sociology of one of its foremost writers. Ratzenhofer's 'Positive Ethik' is extensively quoted from in book four, pages 330-336. Discussions of 'Methode der Soziologie,' and 'Geschichtsphilosophische Konstruktionen,' complete the list of important additions.

This last discussion should be read in connection with his article in American Journal of Sociology, March, 1905, entitled 'An Austrian Appreciation of Lester F. Ward.' Dr. Gumplowicz frankly admits that he is not yet prepared to believe in the possibility of an 'applied sociology,' but, while still holding to

BREEDING BENEFICIAL INSECTS.

Harper's Monthly Magazine is a journal of such high standing and is as a rule so clean and so accurate that anything published in its pages, aside from ostensible fiction, is received by a very large reading public as bearing the stamp of absolute accuracy. It, therefore, becomes necessary whenever an inaccurate statement is published in its pages, and particularly when by such a statement a keen injustice is done to an institution or to an individual, to publish in some way and as speedily as possible an emphatic rejoinder and correction. I, therefore, wish to call attention to the article by H. A. Crafts in the October number of Harper's Magazine, pages 778 to 782, which bears the title of this present communication. The article refers to the excellent work which has been done in California in the breeding of beneficial insects, and more especially to the admirable quarantine carried on by that state against the possible importation of new insect pests. these features of the article no exception can be taken, but there is another and important matter which must be corrected.

Mr. Crafts writes:

To

Mr. Craw [Alexander Craw, late Horticultural Quarantine Officer of California] advised that search be made in foreign countries for the parasite that would destroy the cottony cushionscale.' At that time the state had enacted no horticultural laws, and there were no public funds available for the prosecution of the search suggested by Mr. Craw. But to remedy this defect

private funds were raised, and Professor Albert Koebele, an attaché of the United States Department of Agriculture, was commissioned to make the quest.

Professor Koebele in the course of his travels went to Australia, where he found a grub feeding upon the cottony cushion-scale. He took the grub and developed it to its condition of maturity, and found that it grew into a small beetle known as a ladybird.' At the same time the professor made a second discovery, and that was that a secondary parasite was preying upon the ladybird.'

Knowing that it would be fatal to the project to send the ladybird and its parasite to California together, he set about propagating a colony of the little beetles in close confinement. He accordingly had glass-houses built over two small orangetrees in an orchard that was infested with the cottony cushion-scale, and beneath these he bred up some strong colonies of the ladybirds and sent them to Mr. Craw.

Upon their arrival in California the process of propagation was continued and a large number of the bugs raised.

The insects thus raised by Mr. Craw were sent out in small colonies all over the state wherever there was an orange or lemon orchard affected by the cottony cushion-scale and turned loose in the trees. The result was the speedy cleaning up of the pest, and it has remained in subjection ever since. And thus the great citrus-fruit industry of California was saved.

In these statements Mr. Crafts has done a great injustice to the United States Department of Agriculture, and to the late C. V. Riley, at that time (1888-90) chief entomologist of the department. The facts briefly are these. Prior to the Australian expedition of Mr. Koebele, Professor Riley was in California. He attended, with Mr. Craw, a large horticultural meeting, and the subject of sending abroad for parasites was broached at this meeting. It is quite possible that Professor Riley got the original idea from Mr. Craw. Here, however, Mr. Craw's connection with the introduction ceases; nor do I think Mr. Craw has ever made any personal claim which would in any further way substantiate the statements made by Mr. Crafts, just quoted. Professor Riley returned to Washington, corresponded with entomologists in Australia,

but was unable to devote funds from his appropriation to send an assistant to Australia, for the reason that congress at that time restricted travel to the limits of the United States. There was an exposition that year in Melbourne, and he, therefore, called upon the late Thomas F. Bayard, at that time secretary of state, and urged that the traveling expenses of an assistant be paid, for this purpose, from the funds set aside for the exhibition by the United States at the Melbourne exposition, and of which the Department of State had control. His request was granted, and Mr. Albert Koebele, an assistant in the Division of Entomology, was sent over, his expenses simply being paid by the Department of State and his salary by the Department of Agriculture. Mr. Koebele secured the ladybirds, and in the meantime another agent of the Department of Agriculture, Mr. D. W. Coquillett, stationed at Los Angeles, Calif., had prepared a gauze tent over an infested orange tree. All of Mr. Koebele's shipments were sent direct to this assistant of the division of entomology, and not to Mr. Craw. It was at the Los Angeles station of the division that the insects were propagated, and from which they were sent, and not until considerably later did Mr. Craw, as an agent of the state board of horticulture, have anything to do with the matter. When he did take it up, however, he prosecuted the work very successfully, and during the remainder of his term of office (he is now in the employ of the territorial government of Hawaii) he did a great and good work with other beneficial insects. Thus it will be seen that the introduction and establishment of the ladybirds were done by Professor Riley's assistants, the expenses of Koebele to Australia being paid by the Deparment of State.

It so happened that one of the United States commissioners to the Melbourne exposition was the late Frank McCoppin, and Mr. McCoppin also recommended that the funds for Mr. Koebele's expenses be paid by the Department of State. Mr. McCoppin always claimed, in his lifetime, the full credit for the whole thing, but the facts are as I have stated, and they are within my immediate knowledge,

since at the time I was first assistant to Professor Riley and was intimately acquainted with everything that was going on.

The introduction of this insect was one of Riley's greatest achievements, since it established a principle upon which much good work has since been done in many parts of the world; and it should be stated to his further credit that he was sanguine of success at the start, and that the work was carried through against the predictions of his two oldest assistants, Mr. E. A. Schwarz and myself, both of us having urged against the probability of the establishment in the nearctic life zone of an insect belonging to the Australasian fauna.

To Mr. Craw, therefore, belongs the credit of being, if not the original suggester of the plan, at least one of the first suggesters, and also the credit of having, some time after the introduction and perfect establishment of the insect, had charge of its propagation. To Mr. McCoppin belongs only the credit of having facilitated Mr. Koebele's work by recommending that his expenses be paid from the Melbourne exposition fund. To Riley and the Department of Agriculture belongs the credit of having, by investigations, shown exactly the spot to go for the supposed beneficial insects; for having furnished the man to go to Australia, and having paid his salary; for having induced wholly or partially the secretary of state to consent to the payment of the traveling expenses from the Melbourne exposition fund; for the preparations for the receipt of the beneficial insects at Los Angeles; and for having cared for them and supervised their establishment, propagation and distribution for many months after arrival, thus bringing about the wonderful results which followed. L. O. HOWARD.

NOMENCLATURE AT THE INTERNATIONAL BOTANICAL CONGRESS AT VIENNA.

TO THE EDITOR OF SCIENCE: I have read with much interest Dr. Britton's account in your issue for August 18 of the action in regard to nomenclature taken at the recent International Botanical Congress at Vienna. So far so good. The action seems to have been about what was expected by most Amer