tioned might be studied separately, individual ashes were prepared as just described. In the preparation of the pathologic ashes, the tumors were removed from the decapitated animals, freed from any undesirable portion and ashed in exactly the same manner as were the normal tissues. A portion of each tumor used was reserved for microscopic verification. Preliminary work with the spectrograph disclosed a striking difference of intensity of certain lines common to the spectra of the normal and the pathologic ashes, and showed that this difference varied with the time which elapsed between the striking of the arc and the exposure of the plate. To study this variation, and to make the conditions of the experiments as uniform as possible, the following procedure was adopted. An uncored carbon was drilled with a one-sixteenth inch drill to a uniform depth of three-sixteenth inch. The carbon, so drilled, was placed in a small arc lamp and allowed to burn for three minutes, at the end of which time a spectrogram of the carbon was taken. The hole was then filled with the ash to be tested, the arc struck and a series of exposures made without interrupting the current. To insure exposures of equal lengths and equal intervals between successive exposures, a pendulum bob was swung between the arc and the slit of the spectrograph, the photographic plate being moved while the light was intercepted by the bob. Twelve exposures were made on each plate, each exposure being 1.8 seconds, and the interval between exposures 0.2 second. As the dispersion of the quartz spectrograph used in the above experiments was too small to admit of reliable determinations of wavelengths, recourse was had to a larger instrument. With this, using panchromatic plates, the linear distance between λ = 5300 and λ= 2900 A.U. was 16 cm. The distances between the lines were measured with a photomeasuring micrometer, and the wavelengths read from a large dispersion curve plotted with points obtained from the arc lines of copper. Measurements extended from λ=2680 to λ=4979 A.U. These values check very closely with the wavelengths of sodium as found in Kayser and Runge tables of wavelengths. In practically all cases of the normal tissue ash, the sodium lines, which were of feeble intensity in the first exposure, disappeared after the third or fourth exposure; the rest of the spectrum persisted until the ash had been consumed. With neoplastic tissue ash, the sodium lines in the first exposure were very intense. In most cases, some of the lines of other elements present were very faint, but generally appeared intense in the third or fourth exposure. The intensity of the sodium lines remained constant until all the ash was consumed. Due to the present limited spectroscopic equipment of the Emery Laboratory, we have been unable, to the present time, to substantiate any other possible variations aside from the excess sodium content of neoplastic tissue, but with increased facilities we hope to be able to detect, by means of further study of the emission spectra, absorption spectra and the spark spectra of the vapors given off during the preparation of the ashes, any and all variations which have occurred during the malignant cell change, and the alterations brought about under the influence of radiation. Spectrograms of many different normal and pathologic ashes have been made, using for the pathologic ashes many of the known and recognized strains of experimental animal tumors, as well as spontaneous tumors received from the Wistar Institute of Anatomy and Biology. For the normal tissue ashes, all possible variations of rats-sex, age and breed-were employed. An interesting verification of the above finding was made by titrating with N/100 sulphuric acid solutions made from the normal and neoplastic tissue ashes. The amount of acid found necessary to neutralize the alkali of the neoplastic tissue was more than double that for the normal tissue ash. For the study of surface tension, tissues from normal rats-tumors and irradiated tumors were employed, always using a portion of the same tissues which were at the same time prepared for spectrum analysis. In preparing the material (normal or pathologic tissues) for the surface tension determinations, a weighed amount of tissue was agitated at a uniform rate with ten times its weight of double-distilled water in an alkali-free glass tube and shaking machine, designed and constructed for the purpose. At the end of thirty minutes shaking, the tube contents are transferred to an alkali-free glass tube, well sealed, and allowed to stand for five minutes. After the initial separation has taken place, the supernatant liquid is withdrawn and placed in Pyrex glass tubes and centrifuged at a high speed for ten minutes. The material freed from insoluble particles, is transferred to alkali-free glass containers, sealed, labeled, and is then ready for the tests. For the determinations the du Noüy surface tension apparatus was employed, the ring being flamed between succsesive readings. Our results obtained from tissues prepared as just described, were as follows: (1) The dynamic surface tension of solutions of normal tissue is, in general, lower than that of solutions of pathologic tissue (carcinoma and sarcoma) prepared at the same time. (2) The dynamic surface tension of solutions of both normal and neoplastic tissue kept in closed vessels, in general, increases with time. (3) The rate of increase is less for solutions of normal tissue and tissue which has been radiated than for solutions of untreated neoplastic tissue. (4) The tension reaches a nearly constant value in one to three weeks (depending upon the nature of the solution) which is slightly (one or two dynes) higher than that of distilled water at the same temperature. (5) The temperature coefficient of the tension is greater than that of distilled water, being larger for solutions of normal than for solutions of neoplastic tissue. (6) Upon cooling the solutions to the original temperature, the tension is always lower than at a corresponding temperature on the heating curve, an effect which is more pronounced for solutions of normal tissue. The above results are consistent with the theory that the value of the dynamic surface tension of a solution of tissues is depressed below that of the solvent (distilled water) by the action of the colloidal particles from the tissue and that these particles undergo transformation with time in such a manner that salts are formed which ultimately cause the tension to be elevated slightly above that of distilled water. Due to the presence of excess salts in the solutions of neoplastic tissue, the tensions of such solutions are higher than those of normal tissue, and their rate of increase is more rapid, since the salts tend to coagulate its protein content of the colloidal material. DONALD C. A. BUTTS THOMAS E. HUFF FREDERICK PALMER, JR. HAHNEMANN MEDICAL COLLEGE AND HOSPITAL, PHILADELPHIA, PA. AN ATTEMPT TO CORRELATE THE JOULE TERESIS LOSS IN A SERIES OF IN a very interesting study of the parallelism of the Joule magnetostrictive effect and the hysteresis loss in nickel as different degrees of tension were applied to the rods, Wwedensky and Simanow1 found a very striking correlation between the two. This parallelism between magnetostriction and hysteresis loss seems to be borne out by the work of 1 Wwedensky and Simanow, Ztschr. f. Physik, 38, p. 202, 1926. McKeehan and Cioffi,2 who found that at approximately 81 per cent. of nickel in permalloy no magnetic change in length occurred and also the hysteresis loss was negligible. In the first paper mentioned, this parallelism was obtained by varying the tension and in the second paper by varying the amount of nickel present. The author has been studying3 the magnetic properties of a group of eleven strips of nickel, all cold rolled from the same heat of nickel. These strips were cold rolled to varying thicknesses and thus a series of nickel strips with different degrees of hardness were obtained. If the change in length of these strips for any given field strength and the hysteresis loss are plotted against the hardness values of the same strips, the curves thus obtained ought to show a similarity if the parallelism is a constant for all factors imposed on nickel. Curves showing this relation are given in Fig. 1. The values for the changes in length of the various strips were those obtained when a field strength of 57.7 gauss was applied to each one of the specimens of nickel. The same relation would hold for any other field strength. The hysteresis loss per cubic centimeter per cycle is for Bmax carried to a point of saturation. Curve A presents the relation between the hardness and the contraction of the various strips, while curve B is the corresponding curve for the hysteresis losses. The results seem to indicate that the hardness factor does not produce a parallelism between hysteresis and magnetostriction. S. R. WILLIAMS FAYERWEATHER LABORATORY OF PHYSICS, AMHERST COLLEGE 2 McKeehan and Cioffi, Phys. Rev., 28, p. 146, 1926. 8 Williams, Trans. A. S. S. T., 1926. WASHINGTON UNIVERSITY SAINT LOUIS School of Medicine NEW ADMISSION REQUIREMENTS At least three years of approved college work including specified requirements in the sciences. DEGREE OF B.S. IN MEDICAL This degree may be awarded at the end of the third or fourth year to students fulfilling certain conditions including the preparation of a thesis. DEGREE OF DOCTOR OF MEDICINE Upon satisfactory completion of prescribed four-year course. For catalogue and information, address THE DEAN, Washington University School of Medicine, St. Louis, Missouri Johns Hopkins University SCHOOL OF MEDICINE The School of Medicine is an Integral Part of the University and is in the Closest Affiliation with the Johns Hopkins Hospital. ADMISSION Candidates for admission must be graduates of approved colleges or scientific schools with at least two years' instruction (including laboratory work) in chemistry, and one year each in physics and biology, together with evidence of a reading knowledge of French and German. Each class is limited to a maximum of 75 students, men and women being admitted on the same terms. Applications may be sent any time during the academic year but not later than June 15th. If vacancies occur, students from other institutions desiring advanced standing may be admitted to the second or third year provided they fulfill our requirements and present exceptional qualifications. SCIENCE NEWS Science Service, Washington, D. C. A RELIC OF THE BRONZE AGE A WOOLEN mantle, worn in Sweden when the early Pharaohs still reigned in Egypt, has had its age approximately determined by a curious combination of botanical and geological knowledge, through the researches of Dr. Lennart von Post, of the Museum of National Antiquities at Stockholm. The garment was found buried at a depth of several feet in a peat bed in the district of Vastergotland, carefully folded up and weighted down with three stones, but with nothing about it to indicate how it got there. Its similarity to Bronze Age garments from Denmark and elsewhere suggested its antiquity. The fact that it had evidently not been buried, but had lain in its hiding place while the moss grew over it to form about five feet of peat, was further evidence of great age. The acid water of the bog had preserved it from decay during the centuries. Dr. von Post found the key to its age in the pollen grains that were thick in muddy particles clinging to the fabric. Most important among the species represented were oak, linden and elm, with pine, birch and alder, and hazelnut as the principal shrub. Exact counts showed that the proportion of the pollen from the oak-linden-elmforest was larger than it would be in a Swedish springtime "pollen rain" of to-day, indicating the existence of a milder climate in the North at the time the mantle was laid away. Such a mild climate is known from geological evidences to have followed shortly after the disappearance of the last patches of glacial ice in the south of Sweden, at about the time the New Stone Age was giving way to the Age of Bronze in that country. It was followed by a period of severer climate, ushering in the Iron Age. This mild-climate pollen thus determines the former owner of the mantle, who so carefully folded it up and hid it under three stones in a ditch as a man of the Early Bronze Age. The careful workmanship of the weaver, who made the cloth out of a mixture of fine wool and the hair of game animals, probably deer, is described by Emelie von Walterstorff, and the possible romantic history of the garment, which has a number of dagger-holes jabbed through it, is hinted at by Sune Lundquist. Mr. Lundquist states also that the toga of the Romans was quite similar in shape to these elliptical Bronze Age mantles, though differing in size and manner of wearing. shorter Roman cloak, the "trabea," worn largely by priests and soldiers, was even more nearly similar. A INFLUENZA AND DOG DISTEMPER HOPE is expressed by the British Medical Research Council, in its recent annual report, that a solution of the influenza problem may come from research in progress on dog distemper. Since distemper in dogs is very similar to influenza in human beings, it is thought that the right weapons for attack on influenza may be forged b the experimental study of the animal diseases most closel resembling it. This beam of light into the fog of the influenza prop sition is dimmed somewhat, however, by the fact that i four years of research instituted by the Field Distemp Fund, workers have not succeeded in cultivating t causative virus outside the animal body. Ferrets, whi are highly susceptible to the disease, can be immuniz by a killed or inactivated virus, but this weakened vir gives only temporary immunity to dogs. The suscep bility of individual canines to distemper varies great thus adding to the difficulty of testing the effect of p tective vaccination. In order to make immunization of dogs practical, medical authorities, a virus of known and const potency must be obtained, the dosage of which can accurately standardized. Until the virus can be cu vated outside the animal body the protection afforde incomplete and uncertain. A practical method can be reached when the nature of the virus and its law behavior have been ascertained more completely. W and if these facts are established, however, they constitute definite signposts to follow in the still obscure and dangerous disease afflicting man. THE PREVALENCE OF COMMON COLI THE common cold goes to the head of the list cause of lost time. In a survey of absences from in a big industrial firm over a period of ten years completed by statisticians at the U. S. Public H Service, it was found that colds caused a time loss e lent to 1.4 days per year for every man on the pa and 2.1 days per annum for every female emp Colds were directly responsible for 39 per cent. of absences among the men and for 31 per cent. amo women. Diseases of the general type known as resp caused approximately half of all the absences, bu not so common among the women as the men. it would appear from these records, are more li disablement from nervous disorders and diseases throat and tonsils, but their disabling illnesses are on the whole than the men's. This condition in f the so-called weaker sex is counterbalanced, how the fact that their absences were more numerous, t 14 calendar days apiece during the whole te while that of the men reached only 8.9. A high proportion of illnesses occurred am younger employees, notably among the wome statisticians suggest that this circumstance m: part accounted for by the dropping out of healthy. The group representing the ages 30 to state, seems as a whole to have a greater resis colds, tonsilitis and stomach disorders than the ages. School of Tropical Medicine of the University of Porto Rico under the auspices of COLUMBIA UNIVERSITY San Juan, P. R. An institution for the study of tropical diseases and their prevention. New building containing well equipped laboratories and library. Clinical facilities in general and special hospitals. Field work in cooperation with Insular Department of Health. Courses in bacteriology, mycology, parasitology, pathology, food chemistry, public health and transmissible diseases, open to graduates in medicine and others having equivalent preparation. Number of students limited. First term of second session begins Oct. 1, 1927; second term, Feb. 1, 1928. Special students and investigators admitted at other times as space and circumstances permit. In all cases arrangement in advance is advised. For further information apply to LIVING BULLFROGS We are just recovering from the acute shortage due to the unprecedented drouths of 1924 and 1925. Be sure to reserve your next year's supply while in season, March, April or May. Correspondence solicited. 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