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does not lead one to suppose that the ultimate destination of the food in metabolism is a factor in deterof mining its specific dynamic effect, since this effect depends primarily on the concentration of nutrient material within and around the cells. For a given intake of food, any factor that would tend to vary this concentration during absorption would have a corresponding effect upon heat production. This nutrient concentration in the tissues would be depressed by any factor increasing the rate of disposal of the excess food material, such as muscular activity or mammary activity. Hence, on the basis of Lusk's theory, one would expect a smaller heating effect of a given amount of food in a lactating cow than in a dry cow, though no constant difference would be expected for different amounts of milk produced and different amounts of food consumed. If the cow is a high producer, it is evident that in the first few months of lactation, when the animal is in a condition of "physiological underfeeding," the food consumed would presumably exert only a minimal heating effect,12 and would thus possess a high net energy value. In the later stages of lactation, when the animal may be laying on fat due to overfeeding, the heating effect of the same amount of food may be much greater, if the rate of fat deposition is much less than the rate of milk formation, as it quite probably is. At this time, the net energy value of the food would be less than at first.

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On similar reasoning, it would appear that the net energy value of food fed at the maintenance or submaintenance level would be higher than at the higher levels, not because of the different metabolic reactions involved in fattening as compared with maintenance, but because of a probable slower rate of withdrawal of nutrients from the intercellular fluids in the deposition of fat than in the satisfaction of contemporary energy requirements. However, the difference would probably not be a constant one, since the heating effect of a unit of food would presumably vary in each case with the level of feeding. On the same grounds, it would be expected that the net energy value of food would be greater when muscular activity is occurring simultaneous with absorption of food from the intestinal tract, than when the animal is at rest; on the other hand, work performed in the post-absorptive period would be without influence on the utilization of food energy. J91b9a98

12 Thus, Widmark and Carlens (Biochem. Z., 1925, clvi, 454) observed that the blood sugar content of lactating cows was less than that of dry cows, and that the depression from the normal value was in rough proportion to the amount of milk produced. The lowest values observed were less than half (0.040 per cent.) the average value for dry cows (0.085 per cent.).

It appears, therefore, that Lusk's experimental work affords no grounds for believing that the manner in which food is utilized determines the extent of utilization through its effect on the specific dynamic action of the food. It is true that the net energy value of a food may be expected to be different with animals functioning in a different manner, but it would seem that no characteristic or even approximately constant net energy value can be assigned for a given function, and that no constant relation of net energy values among different functions can be assumed. In particular, it appears unjustifiable to assume that, in an animal utilizing food in a number of different ways, so much metabolizable energy is being used for maintenance, and so much for milk production, since, if mammary activity increases the net energy value of the food by preventing as great a "metabolism of plethora" as would otherwise occur, this increased utilization would apply as much to the food used for maintenance as to that used in the production of milk.13

Another possible explanation of the heating effect of food on animal metabolism is that the acid products of digestion may be effective stimuli to cellular activ

13 A specific illustration of this point may aid materially in appreciating this argument. In a recent article by Forbes, Fries, Braman and Kriss (2), estimates are made of the utilization of metabolizable energy for milk production, by making certain definite assignments of metabolizable energy for maintenance and body increase, and relating the remainder to the energy content of the milk produced. Thus for Cow 874 (in Tables 5, 6 and 7) it is assumed that the metabolizable energy used for maintenance suffers a loss of 22.3 per cent. as heat, that used for body gain a loss of 38.4 per cent., and hence that used for milk production a loss of 27.8 per cent. The total heat increment for this cow is an experimental observation, but the factoring of it in this manner on the basis of results obtained on the cow when dry is an interpretation that involves theoretical considerations that have neither been justified nor discussed. Hence, the conclusion that the percentage utilization of metabolizable energy for milk production was, for this cow, 72.2 per cent., is an interpretation of the same character. The essential assumption upon which these interpretations are based is that when food is serving a number of purposes in the animal body simultaneously, the utilization of food energy for each purpose is independent of that for the other purposes; in other words, that the heating effect of food used for maintenance is the same whether the animal is producing tissue or milk simultaneously or whether it is only maintaining its status quo. While this assumption superficially appears to be a reasonable one, on analysis it is seen to imply that the causes of the heat increment due to the ingestion of food are related directly to the methods of food disposal, i.e., to the metabolic reactions concerned in maintenance, body gain and milk production.

ity. This explanation has been proposed by Benedict,1 ,14 though direct attempts to verify it have not been successful.15 It is conceivable, however, that acid stimulation may be an important factor with ruminants, in which large amounts of organic acids resulting from extensive bacterial fermentations are absorbed from the intestinal tract. But obviously this theory also can not be construed to favor the view that a definite net energy value for a food is characteristic of each animal function, or that the percentages of utilization of metabolizable energy for different functions bear a constant relation to one another.

Finally, in ruminants at least, the chemical, bacterial, glandular and muscular events occurring in the alimentary canal, or in its accessory organs, during digestion are known to result in a definite and considerable increase in heat production, an increase that may account for a large percentage of the total heat increment following the ingestion of food. But it appears that these events, and the accompanying heat losses, would bear no relation to the events subsequently or simultaneously occurring on the other side of the gastro-intestinal mucosa. They would presumably be related, more or less constantly, to the amount of food consumed, and its physical and chemical make-up, particularly as this bears upon the extent and rapidity of its digestion, but would be quite unrelated to the manner in which the food is utilized after absorption.

It appears, therefore, that the determination of the relative net energy values of feeds for animals in different functional conditions is being approached on the basis of assumptions, not only without experimental justification, but even in contradiction to established experimental findings. The results obtained, in consequence, are being given a significance that they do not seem to possess, in all probability. Hence, a different working hypothesis should be adopted. Since Lusk's experimental work and the theories that he has deduced from it appear to offer the most plausible explanation of the specific dynamic action of food-the only calorigenic effect of food that would conceivably be related to its disposal in metabolism-a working hypothesis based upon these theories would seem to be the safest guide in future investigations of the net energy values of food for farm animals.1 16 In a broad way, these theories differen

14 Benedict, F. G., Trans. 15th Intern. Congress Hyg. and Demography, Washington, D. C., 1912.

15 Lusk, G., J. Biol. Chem., 1921, xlix, 453; Taistra, S. A., ibid., 479; Chanutin, A., ibid., 485.

16 It may, of course, be objected that Lusk's work was done with carnivora and that the conclusions from it can not be assumed to apply to herbivora. However, there is

tiate three general lines of investigation, involving studies of (1) the heating effect of different amounts of food in animals in the same functional condition, (2) the heating effect of the same amount of food in animals in different functional conditions, and (3) the influence of internal factors, such as heredity and endocrine activity, upon the specific dynamic effect of food. The first study is concerned with the rate of establishment of the metabolism of plethora, the second with the rate of its depression due to withdrawal of food by the tissues and the third with the response of the tissues to a given plethora stimulus; in other words, with the irritability of the tissues. H. H. MITCHELL

COLLEGE OF AGRICULTURE, UNIVERSITY OF ILLINOIS

RALPH GORDON LUSK

DR. RALPH GORDON LUSK, instructor in geology at Harvard University, died suddenly with heart failure in New York City on July 27, at the age of thirtyone years, just as he was entering upon his career as a geologist. He was born July 14, 1896, at Manchester, Iowa, where his father, the Reverend C. F. Lusk, was at that time pastor of the First Baptist Church. His mother's maiden name was Grace A. Hilbrant. Ralph Lusk was educated in the public schools of Iowa, and in March, 1918, he enlisted in the U. S. Navy and was sent to the Great Lakes Naval Training Station. On April 1 of the same year he was married to Neva Belle Frederick at Lake City, Iowa. At Great Lakes, the heart ailment which finally caused his death was first developed and by September he was discharged for vocational rehabilitation. He entered Denison University that fall and graduated with the class of 1922, after making geology his major subject. The next year was spent as a graduate student at the University of Chicago. At Denison he was elected to membership in Phi Beta Kappa and at Chicago to Sigma Xi. In 1923-24 he was instructor in geology at Denison and in 1924 he entered Harvard University as an Austin Teaching Fellow in Geology. He was appointed instructor in geology in 1926 and in June, 1927, he was awarded the degree of doctor of philosophy at Harvard, having previously received the degree of master of science from Chicago.

little reason for believing that the energy metabolism of the two types of animals is fundamentally different. In any case, the theories of Rubner as well as those of Lusk were based upon experimental work with carnivora. Until there is definite reason for doubting the applicability of experimental data so obtained to farm animals, they may be considered a safe guide upon which to base working hypotheses.

During the summer of 1922, Ralph Lusk had served as field assistant to Kirtley F. Mather, of the U. S. Geological Survey, in Colorado and New Mexico. Shortly thereafter he was appointed assistant geologist on the survey and spent the summer of 1923 in Montana as assistant to A. J. Collier. Similarly during the field season of 1924 he was engaged in geological mapping in northeast Colorado for the United States Geological Survey, and during the field season of 1925 and 1926 he was in eastern Tennessee as geologist of the State Survey. This field work supplied the basis for his doctor's thesis as well as shorter technical articles. He was also one of the joint authors of a government bulletin, now in press, descriptive of the oil and gas resources of northeast Colorado.

Dr. Lusk was a member of Beta Theta Pi and a Mason. He is survived by his widow and four children: twin daughters, aged eight; a son, Ralph Gordon Lusk, Jr., aged four, and a baby daughter, nine months old.

HARVARD UNIVERSITY

KIRTLEY F. MATHER

PROFESSOR ALBRECHT KOSSEL GEHEIMRATH PROFESSOR ALBRECHT KOSSEL, until recently professor of physiology in Heidelberg University, director of the Heidelberg Institute for the Study of Proteins, Nobel prize winner, known for his elucidation of the chemistry of the proteins and of nuclear chromatin matter, died unexpectedly, after a very short illness, in Heidelberg on July 5.

Professor Kossel in a very real sense was the founder of modern biochemistry. It was his conception of the structure of the proteins, following upon his study of the simplest of these substances, the protamines, a conception which was confirmed and established by synthesis of artificial or synthetic proteins by Emil Fischer, work undertaken at Professor Kossel's suggestion and request, which gave to biochemistry its great impetus in the last years of the nineteenth century and led to the wonderful outburst of activity in this field.

Professor Kossel was a fine-looking man of medium height, of a simple, friendly, affectionate and generous nature. He had nothing of the insolence, conceit and arrogance so often associated with the Prussian, but he was a real scientific man, modest, kindly, simple, sincere, with a brilliant imagination and indefatigably at work in the laboratory even up to the time of his death. He retained his youthfulness of appearance, of mind and outlook and all of his faculties to the very end of his life. To his great honor it may be recalled that he did not sign the ridiculous

pronunciamento of the German professors at the start of the great war. He did not sympathize with those who brought on the war, although after his country was engaged he gave it loyal support.

Ever since the death of Hoppe-Seyler he had been editor of the Zeitschrift für Physiologische Chemie, being associated for a year or two and until the death of the latter with Professor Baumann, but being thereafter sole managing editor. This journal, established by Hoppe-Seyler about 1879, was for many years the only journal in the world devoted exclusively to biochemistry and it is one of the finest journals of science of the present day, its papers being almost without exception valuable contributions to the subject and several of them being classics in their fields.

Mrs. Kossel, whom many American students and friends will remember with great affection for her kindness, sincerity and intelligence, and who was related to some of our most distinguished scientific men, died in 1912. Two children survive them; a son, the distinguished physicist of Kiel, Professor Walther Kossel, and a daughter, Gertrud Kossel; and three grandchildren, Albrecht, Dierick and Irene Kossel. Professor Kossel was a brother of the bacteriologist, Professor H. Kossel, who died about two years ago.

Professor Kossel had many pupils, his laboratory in Heidelberg being filled before the war with students from all lands. His death is felt by them all as a great personal loss. It removes another of the great men of science of Germany, the greatest glory of that country in the years just preceding the war. As one after another of these great men pass away it is as if one light after another were being extinguished and Germany entering again into the twilight of learning.

ALBERT P. MATHEWS

SCIENTIFIC EVENTS

THE IMPERIAL AGRICULTURAL RESEARCH CONFERENCE

THE Imperial Agricultural Research Conference which opens in London on October 4 has, according to a report in the London Times, as its main objects the establishment of closer cooperation in agricultural research work throughout the empire, the setting up of additional research stations in tropical and subtropical countries, the creation of greater imperial bureaus, and the recruitment, training and interchange of research workers. It will be attended by seventyfive delegates of high administrative and scientific standing from the oversea parts of the empire and. by many representatives from Great Britain and

Northern Ireland. The Dominions and India are sending thirty delegates, and representatives of the Colonies and Protectorates will attend from Barbados, British Guiana, Ceylon, Cyprus, Gold Coast, Kenya, Leeward Islands, Malaya, Mauritius, Nigeria, Nyasaland, Palestine, Sierra Leone, Tanganyika, Trinidad, Grenada and Windward Isles, Uganda, Zanzibar and Sudan.

Lord Bledisloe, the parliamentary secretary to the Ministry of Agriculture, is the chairman of the organizing committee, and the members of the conference, in addition to various representatives of the Ministry of Agriculture, the Colonial Office and the Board of Education, include the High Commissioners for the Dominions, representatives of the Empire Marketing Board, the Department of Scientific and Industrial Research, the Medical Research Council, the Bureaus of Entomology and Mycology, the Overseas Settlement Department, the University Grants Committee, the Department of Overseas Trade and the Forestry Commission.

The importance and value of such a conference was first urged by the Agricultural Research Council several years ago, and since then the matter has been discussed by the Imperial Conference and the Colonial Office Conference. Recently Lord Lovat's Committee on Agricultural and Research Administration in the non-self-governing Colonies put forward recommendations for closer cooperation on these matters. The conference will be held in the Grand Committee Room of the Houses of Parliament, and will be opened on October 4 by the Minister of Agriculture. In the evening the delegates will be the guests of the government at a dinner in the Royal Gallery, House of Lords. Till October 7 the full conference will discuss the agenda of administrative questions, and the organizing committee anticipate that this will lead to the appointment of commissions to examine in detail and prepare reports and recommendations on the question of the extension of the system of imperial bureaus from entomology and mycology to other departments of agricultural science. It is probable that recommendations will be put forward for the setting up of empire bureaus in veterinary science and for investigating soil problems and plant breeding, and also for a bureau on agricultural economics. The desire of the Australian Government to set up a research institute at Queensland on subtropical agriculture will also come before the conference. Specialist commissions are to be set up to bring together the delegates interested in a special subject of research and to assist in the formulation of schemes of combined research work. The full sessions of the conference will be resumed on October 24 and continue for four days. During the intervening period part of

a program of visits to research centers will be carried out.

The University of London will hold a reception at the Imperial Institute, and the delegates during their stay in London will have the opportunity of viewing at the Science Museum a special exhibition illustrating the history of agricultural implements and of inspecting at the British Museum manuscripts and books dealing with agricultural science. Arrangements are being made at both museums for lectures on such subjects and special pamphlets will also be provided for the use of the delegates. On October 14 the Vicechancellor of Cambridge University will give a luncheon to the delegates, and after inspecting the various departments of scientific research the party will leave for Edinburgh on October 18. The headquarters of the conference will remain in Edinburgh until October 22. Afterwards delegates will have the opportunity of visiting Aberdeen to inspect the work of the Rowett Institute in relation to animal nutrition and visiting Belfast, where they will be entertained by the Government of Northern Ireland and shown the plant breeding, poultry and animal diseases research stations.

The reports of the various commissions appointed will be considered by the full conference in London between October 24 and 27. On October 29, the party will visit the Rothamsted Experimental Station, on October 31 the Royal Botanic Gardens at Kew, on November 1 the East Malling Research Station, and on November 2 Oxford University, including the Institutes of Agricultural Economics Research, Agricultural Engineering and Imperial Forestry.

THE BIOCHEMICAL INSTITUTE FOR THE MIDDLESEX HOSPITAL, LONDON

THE Middlesex Hospital, already distinguished by the Bland-Sutton Pathological Institute, has now, according to the Journal of the American Medical Association, the further distinction of an institute of biochemistry, thanks to the gift of $200,000 by Mr. S. A. Courtauld. At the opening ceremony, Mr. A. E. Webb-Johnson, honorary treasurer of the medical school, recalled that it was only a few years since Mr. Courtauld gave $100,000 to endow the chair of anatomy, "one of the fundamental medical sciences." The foundations of scientific work in the Middlesex HosSchool were laid by Sir John BlandSutton before the war, by his gift of the pathologic institute bearing his name. "Dictionaries printed before the year 1900 contain no such word as biochemistry, but the name is now familiar, and though new the science is old," said Sir John Bland-Sutton, in an address on "Biochemistry in Relation to Medicine,” a science concerned with the application of the princi

pital Medical Scho

ples of chemistry and physiology to the investigation and interpretation of the phenomena of life. He referred to the fact that the kingdoms of nature had been arranged in three classes: mineral, plants and animals. The microscope revealed myriads of minute living things concerning which biologists were puzzled to decide whether they were plants or animals. Such discoveries bridged the gap between the two, and it was now the ambition of biochemists to discover the connecting link between stones and plants, in order to find out how life arose from inorganic matter. He had always maintained that laboratories for investigating disease should be in close association with hospitals. The future of medicine does not lie in prescribing drugs, he declared. The day may come when, some of us believe, the biochemical laboratory may displace the dispensary. Lavoisier, the founder of biochemistry, had his head lopped off in 1794, continued Sir John, by the "apostles of Liberty, Equality and Fraternity," on the excuse that the republic had no need for scientists. Mr. Courtauld had no fear that such a fate awaited him. The wisdom shown in building the laboratory indicated his appreciation of the great part science played in practical medicine. "We may be hopeful," he concluded, "that a discovery will one day be made within the walls of this laboratory which will make the world gape with astonishment." The institute will be a five-floor building, the four upper ones having laboratories for the study of the various branches of biochemistry, all equipped with the latest appliances.

THE JOURNAL OF PALEONTOLOGY NUMBERS one and two of a new quarterly known as the Journal of Paleontology appeared in July and August, respectively. Numbers three and four are expected to appear in October and December. In future years the numbers will appear at three-month intervals.

The Journal of Paleontology is the official publication of the Society of Economic Paleontologists and Mineralogists.

The Society of Economic Paleontologists and Mineralogists is an organization whose object, as stated in Article II of its constitution, is "to promote the science of stratigraphy through research in paleontology and sedimentary petrography, especially as they relate to petroleum geology," and whose membership is composed of members or associate members of the American Association of Petroleum Geologists engaged in such work.

The Journal of Paleontology will be devoted to research in paleontology and sedimentary petrography. The paleontological papers will include those pertaining to faunal distribution, stratigraphic index

species, descriptions of individual faunas, relation of zones to habitats, etc. Sedimentary petrographical papers will pertain to mineral zones, stratigraphic distribution, provinces of sedimentation, etc. Papers will also be included which pertain to technique bearing on researches in paleontology and sedimentary petrography. In fact, those papers will be included which will in any manner be helpful to those engaged in stratigraphic studies carried on either in the laboratory or in the field.

The Journal of Paleontology is a quarterly publication, and will be of approximately 96 pages and 15-20 plates. It is 634 x 912 inches in size.

Dr. Joseph A. Cushman is editor. He is one of America's most active micro-paleontologists. He has been engaged in research for many years, and is now one of the world's foremost authorities on the foraminifera. He will have associated with him an editorial board to assist in matters not in his particular field.

MARCUS A. HANNA, Secretary-Treasurer.

SOCIETY OF ECONOMIC PALEONTOLOGISTS
AND MINERALOGISTS,
HOUSTON, TEXAS

THE RAWSON-MACMILLAN ARCTIC EXPEDITION OF FIELD MUSEUM

WILLIAM DUNCAN STRONG, anthropologist of the expedition and a member of the staff at Field Museum of Natural History, in a report made public by the director of the museum, tells how the explorers have come upon the ruins of the house, the mining pits and the improvised shipyard of Sir Martin Frobisher, who, between 1576 and 1578, led three expeditions, two for gold, into the forbidding regions of Labrador and Baffin Land. Digging in the ruins, Dr. Strong has unearthed fragments of brick, plaster, coal and porcelain, products which he states undoubtedly were brought over from England, and are indisputable proof that the ruins are of European, and not native Eskimo, habitations.

The story of Frobisher, recalled by the museum expedition's findings, is one of the most romantic in the history of quests for riches in far parts of the earth. Frobisher, with the financial assistance of a few friends, sailed from England in July, 1576, in search of a northwest passage to Cathay and India. He had two tiny vessels, The Gabriel and The Michael, and thirty-five men. Arriving in Labrador, they proceeded up the coast to what is now Frobisher Bay in Baffin Land. Five of the men were captured by natives and never seen again. Failing to find the passage they sought, the expedition returned to England, bringing some specimens of what the sailors called

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