mouth in defense. No individual, scientist or layman could play loosely with the open mouth of that snake. A. H. WRIGHT CORNELL UNIVERSITY ADDITIONAL evidence for the poisonous character of the coral snake has recently been given by the professor and students in the summer forestry school of the Louisiana State University at Bogalusa, Louisiana. To those of us who live in the territory of the coral snake it seems extremely important that the poisonous nature of this snake be emphasized whenever and wherever possible. The article by E. R. Dunn, of Smith College, in SCIENCE for October 2, is thus further reinforced by the following facts: A beginning student in the forestry school of the State University at Bogalusa, Louisiana, was bitten at eight o'clock in the morning by a snake which he believed to be non-poisonous. The professor in charge helped other students apply a tourniquet and sent the boy at once to the nearest hospital. The physician who looked at the wound treated it as one would any other, removed the tourniquet and sent the boy home. By three o'clock that afternoon the boy was feeling so ill that his family sent for the best physician available. The doctor saw that a slow paralysis was already setting in and ordered the boy to the hospital. But in spite of all that could be done the patient died before six the next morning. The wound was on the finger and though deep was certainly not of such a nature as to have produced death except from the venom. Subsequent comparison of the accounts of the onlookers (the snake unfortunately escaped) establishes as a practical certainty the identity of the snake as Elaps, our coral snake. LOUISIANA STATE UNIVERSITY E. H. BEHRE NOMENCLATURE OF VITAMINES FUNK's proposal in the matter of the nomenclature of the vitamines1 proves the desirability of an international agreement. The term D accepted by Funk for the designation of the yeast growth promoting factor is already used by others for the anti-rachitic factor. This, however, is termed by Funk E; unfortunately, E is claimed by Barnett Sure to use instead of Ewan's and Bishop's substance X, or the reproduction factor, which in Funk's scheme is termed F! E. C. VAN LEERSUM DIRECTOR, NETHERLAND INSTITUTE OF NUTRITION, AMSTERDAM 1 SCIENCE, 62, 157, 1925. QUOTATIONS INTERNATIONAL COOPERATION IN SCIENCE ONE section of the work of the League of Nations which received prolonged consideration at Geneva during the recent assembly is that known as intellectual cooperation. A year ago the assembly authorized the establishment in Paris of an International Institute of Intellectual Cooperation, to be under the control of the league, but subsidized by the French government. The choice of Paris was criticized at the time because it suggested that France had some preeminence in culture, but ultimately the proposal secured something like unanimous approval. The institute has now been definitely constituted, and will be in full working order during the present year. The French government is supporting it at an estimated annual cost of two million French francs. The director is M. Julien Luchaire, inspector-general of public education in France and laureate of the French Academy. M. Luchaire a fortnight ago gave the delegates assembled at Geneva an account of what has been already done and what it is proposed to do. He said that the institute had been organized in seven sections—namely, general relations, university relations, bibliography and science, legal relations, literature, art and information. The chiefs appointed to these sections are, respectively, an Englishman, a Pole, a German, a Spaniard, a Chilian (a lady), a Belgian and an Italian. To the science section a very ambitious program is committed. In the first place, it will endeavor to organize an international analytical bibliography in all branches of science. So far as physics is concerned, a large number of reviews publish articles on this subject, and there are three reviews which prepare a fairly wide analytical bibliography, but hitherto these have competed uselessly with one another, while being individually incomplete. The Committee on Intellectual Cooperation has had a meeting with the directors of these three publications, and an agreement has been reached whereby, through a division of the work, physicists of all nationalities will have an opportunity of becoming fully and immediately informed of the immense production throughout the world in this branch of science. Another task before this section of the institute is to create a liaison between the libraries of all countries, particularly with a view to arranging specialized centers for the collection of scientific documents. A system for the international loan of books and the exchange of scientific publications is also to be brought into being. Investigations are to take place with a view to the set بار The ting up of new international institutes of research, and measures likely to encourage young people de10 voted to scientific research are to be examined. Then the unification of nomenclature and of standards of measurement in certain sciences is to be attempted; a beginning has already been made with regard to the terms employed in nosology. Another task proposed is the diffusion by means of analytical summaries of scientific work performed by nationals in countries whose language is not widely known. Among the questions referred to the section charged with general affairs is the setting up of an organization for the preparation of youths for international careers. question had already been considered by the committee on Intellectual Cooperation sitting at Geneva of the establishment of an international university or an institute of international studies under the auspices of the league, and now the Paris institute is to give the question a more detailed examination. A scheme for study tours and exchange of students of all countries has also been approved. Another proposal, from Rumania, is the flotation of an international loan for the restoration of science in certain countries, particularly those which suffered most severely from the war. The information section of the new institute is to examine questions concerning books-for example, the question of introducing uniformity of size and paper measure, and of undertaking a campaign against the use of papers and inks of inferior quality whereby the printed record is likely in course of time to be destroyed. M. Luchaire concluded his address with an eloquent tribute to M. Henri Bergson, who has been chairman of the Committee on Intellectual Cooperation since its foundation, but was unable to go to Geneva this year owing to ill health. He spoke of Bergson as a great citizen of the intellectual world who had devoted all his time during recent years to the work on intellectual cooperation, giving second place even to those philosophical speculations which had been his glory and his delight. A telegram of greeting and homage was sent to M. Bergson from the delegates at Geneva.-British Medical Journal. SCIENTIFIC BOOKS Introduction to Theoretical Physics. Volume I. By ARTHUR HAAS, professor of physics in the University of Vienna; translated from the third and fourth German editions by T. Verschoyle. Pp. xvi-331, D. Van Nostrand Company, New York, 1924. Price $6.00. THE wonderful progress of physical science in recent years has made an understanding of the fundamentals of theoretical physics increasingly necessary for every physicist or physical chemist. While an introductory course on theoretical physics has been more or less standardized in continental universities since C. Christiansen's "Elements of Theoretical Physics" appeared in German translation in 1894, such a course is hardly yet universal in this country. This has been due, in part, to the lack of a suitable textbook in the English language. In view of this fact the appearance of an English edition of Professor Haas's book must be considered an event of great importance. The object of this book is to give a survey of the fundamental principles of theoretical physics that will prepare the student for the study of original papers and monographs on modern physics. The first volume is devoted to classical physics and in it no use is made of atomistic hypotheses. It deals with the principles of mechanics, with the general theory of vector fields, of vibrations and of potential, and also with the theory of the electromagnetic field and of light. At the end of the volume is given a very useful summary. The second volume will take up atomistic and non-classical physics. The ground covered is treated with great clarity and pedagogical skill. Only a minimum of mathematical knowledge is assumed (even the process of differentiation is explained) and no steps are left out in the calculations. This feature makes the book particularly valuable for self-study. By placing the developments of all purely mathematical relations in separate sections their abstract and general character is emphasized and confusion avoided between mathematical form and physical contents. Systematic use is made of vectorial methods throughout the volume. With the thorough and complete development given of the general principles, it has, of course, been necessary to leave out examples and applications to special problems. The reviewer has found only one real error in the book. On page 160 the stress in a deformable body is assumed to be a vector instead of a tensor, and the proof given for the symmetry of the stress tensor as well as the derivation of the surface-force acting on an arbitrary surface-element are therefore illusory. A few of the sections on the theory of the electromagnetic field are less satisfactory than the rest of the book. The author, when applying the results from the chapter on potential theory to electromagnetism, has not always kept clearly in mind that these results are purely mathematical. It would also have been more natural to start with Biot and Savart's law, with which the student is already familiar, rather than with the general law for the magnetic field of a closed circuit. SPECIAL ARTICLES THE STRUCTURE OF HIGH- (OR B-) AT temperatures below 575° C. crystals of quartz have the symmetry of the enantiomorphic hemihedral class of the rhombohedral division of the hexagonal system (point group 3D). An inversion takes place at this temperature, however, and above 575° C. the symmetry is increased to that of one of the truly hexagonal crystal classes. When a- (or low) changes to ẞ-quartz a single crystal of the former becomes transformed into a single and similarly oriented crystal of the latter. This fact permits the investigation of the X-ray diffraction effects from single crystals as well as from crystalline aggregates of B-quartz. Powder, Laue and spectrum photographs have been made from B-quartz in the course of a series of X-ray diffraction studies of crystals at elevated temperatures. The data from these photographs have been found to be sufficient to yield a unique solution to the problem of the atomic arrangement in this form of silica. A print has been published of a Laue photograph of quartz above its inversion point. Spectrometer measurements3 from several simple planes have also been recorded. No structure, however, has been deduced from either of these earlier sets of observations. α = Crystallographic measurements have shown ẞ-quartz to have an axial ratio very close to that of a-quartz -CB=1.0926 as opposed to c = 1.0999. The hexagonal unit cell of a-quartz which agrees with all attainable diffraction data has dimensions a。 = 4.903A°,5 c=5.39,A° and contains three molecules of SiO2. 1 A paper (J. Soc. Glass Technology, Sept., 1925) has just appeared in which W. H. Bragg describes a structure for B-quartz. His atomic arrangement seems to be essentially identical with the one deduced here. 2 F. Rinne, "Die Kristalle als Vorbilder des feinbau lichen Wesens der Materie" (Berlin, 1921), p. 35. 3 R. E. Gibbs, Proc. Roy. Soc. A, 107, 561 (1925). 4 R. Grossmann quoted in F. Rinne, op. cit., p. 89. 5 M. Siegbahn and V. Dolejsek, Zeit. f. Physik, 10, 159 (1922). The only simple unit cell for B-quartz that can account for the data from powder photographs and from six Laue photographs is a similar one with a=5.01A°, co=5.47A°. Since the density of Bquartz is known to be (585°)=2.518, its unit cell likewise must contain three molecules of SiO2. The hexagonal, rather than trigonal, symmetry of B-quartz is immediately apparent from the Laue photographs taken with the X-rays normal to the base (001). Since quartz above its inversion still shows rotary polarization, its class of symmetry must be either 6C or 6D. Crystallographic observations? have been supposed to point quite conclusively to the latter. If this selection of crystal class is assumed to be correct, the following deduction leads uniquely to a structure for B-quartz which is in satisfactory accord with experiment. The X-ray diffraction effects arising from atomic arrangements built upon the space groups isomorphous with 6D differ in the nature of the reflections observed from the plane (00-1). The present powder and spectrum photographs from B-quartz agree with the previous spectrometer measurements in showing only 3rd, 6th, etc., orders from this face. Its corresponding space groups consequently prove to be the enantiomorphic pair 6D-4 and 6D-5. There are numerous ways of arranging three silicon and six oxygen atoms according to the demands of these groups. All those structures which put oxygen atoms in special positions (a)-(f) are excluded by the presence of first-order Laue reflections from planes (2m, 2n.p), where m, n, and q are any integers and p3q. The eight remaining structures are obtained by combining (a) and (c), as silicon positions, with (g), (h), (i) or (j), as oxygen positions. Four of these, (a) (g), (a)(i), (c)(g), and (c) (i) place the oxygen and silicon atoms in the same planes parallel to (001). If, then, one of these groupings were the correct structure, the observed 3rd, 6th, etc., orders from the base should show a "normal decline" of intensity with order. Both the spectrometer observations10 and spectrum photographs indicate that 6 A. L. Day, R. B. Sosman, and J. C. Hostetter, Am. J. Sci., 37, 1 (1914). 70. Mügge, Neues Jahrb. f. Min., u.s.w. Festband, 1907, p. 181. 8 P. Niggli, "Geometrische Kristallographie des Discontinuums" (Leipzig, 1919), p. 493; W. T. Astbury and K. Yardley, Trans. Roy. Soc. (London), 224A, 221 (1924). These designations of atomic positions are the ones used in R. W. G. Wyckoff, "An analytical expression of the results of the theory of space groups" (Washington, 1922), p. 165. 10 R. E. Gibbs, op. cit. 00-1(3) is not stronger than 00-1(6). These four arrangements may thus be excluded from further consideration. Each of the four remaining possibilities (a)(h), (a)(j), (c)(h), and (c)(j) has only one variable parameter. It is consequently entirely feasible to calculate the nature of the diffraction effects to be expected from them for different values of the variable parameter u. A comparison of the results of such calculations with the principal aspects of the powder photographs and with the important intensity anomalies observed in the Laue photographs from B-quartz serves to eliminate all these structures except (c)(j). If in grouping (e) (j) the parameter u is chosen close to 0.20, then excellent agreement is found between calculated and observed intensities.11 It can hence be concluded that the structure of B-quartz is that of the two enantiomorphic arrangements 6D-4, (c) (j) and 6D-5, (c) (j). The coordinate positions of the atoms in the hexagonal unit of 6D-4, for instance, are Silicon Atoms: (c); 0 1 0; 1 0 Oxygen Atoms: (j) u u §; 2u, u, †; u, 2u, k; u u §; 2u, u, †; u, 2ũ, †, where u has a value in the neighborhood of 0.20. This structure agrees with the one deduced for B-cristobalite12 in placing a tetrahedron of oxygen atoms about each silicon atom. In cristobalite this tetrahedron was necessarily regular; symmetry does not require such a regularity in quartz, but the value found for u is such as to bring about at least an approach to this condition. From data now being obtained through the analysis of prism face Laue photographs it is hoped to be able to limit the oxygen parameter more narrowly, and thus to gain a more quantitative measure of this approach to regularity. No molecules of SiO, could be distinguished in crystals of B-cristobalite; neither does this structure for B-quartz show clear evidence for SiO, or (SiO2)x molecules. Though their Laue photographs exhibit very different intensities of reflections, the powder photographs of a- and of ẞ-quartz are astonishingly similar. This is precisely what would be expected if the change from one form of quartz to the other involves only a relatively slight atomic rearrangement. The numer 11 Arrangements (a) (h) and (a) (j) would not have been expected because they make the three silicon atoms all lie on a single axis and thus place them closer together than previous experience has indicated as probable; similarly (c) (h) is unlikely because it associates oxygen atoms more intimately with one another than with silicon .atoms. 12 R. W. G. Wyckoff, Am. J. Sci., 9, 448 (1925). ous other known facts about quartz agree with this supposition. A more detailed description of this structure, together with a statement of the extent to which it agrees with experiment, will be published in the American Journal of Science. This experimental evidence and a tabulation of the distinguishing criteria for all special cases of the hexagonal space groups will appear in the Zeitschrift für Kristallographie. RALPH W. G. WYCKOFF GEOPHYSICAL LABORATORY A NEW METHOD FOR THE STUDY OF SOFT X-RAYS1 A NEW method for determining ionization and resonance potentials is found and applied in determining such critical limits of the elements composing photographic emulsions. At this writing the soft X-ray region between 100 and 750 volts has been studied. A beam of electrons, having velocities uniformly distributed over the range under investigation, is spread into a band by means of a magnetic field. The velocity possessed by the electrons in any given part of this band is determined from the geometry of the apparatus and the strength of the magnetic field. Photographic plates exposed to such a band show sharp discontinuities when developed. The photographic emulsions contain the following elements which have critical potentials within the range studied: carbon, nitrogen and oxygen in the gelatin; and silver and bromine as silver bromide. The discontinuities observed in the blackening of the photographic plate are in good agreement with observed and calculated critical potentials for these elements. Table 1 contains a list of the critical potentials observed in this work with the interpretation assigned to each. In assigning the interpretations given in this table both the absolute values and the difference between levels have been considered. The authors do not wish to make any claims for attainable refinements, but it is obvious that such uncertainties as initial velocities of thermally emitted electrons, contact potentials and potential drops along filaments are eliminated. UNIVERSITY OF CALIFORNIA G. K. ROLLEFSON Е. Ј. Ротн THE NUMBER AND ARRANGEMENT OF FLAGELLA OF THE TYPHOID FEVER GERM, BACILLUS TYPHI IN staining various bacteria for flagella by a method developed by the writer (which will be described elsewhere), Bacillus typhi Gaffky (B. typhosus Gaffky) happened to be included. As quite a few preparations have been obtained of this germ, showing very clearly the number and arrangement of flagella, it seems desirable to call attention to the findings, especially as they are not in agreement with various statements and figures presented in quite a few well-known text-books and articles. Two cultures, at different times, were obtained from the U. S. Army Medical Museum, and the preparations obtained from both were in very close agreement. Furthermore, the same staining method has been used by several classes of students in bacteriology, University of Arkansas, using the typhoid germ and with the same results. Altogether, some fifty excellent preparations have been studied by the writer and several clear-cut microphotographs have been obtained. From these studies the following conclusions are drawn. First, the number of flagella for each organism varies from one to several (rarely more than four), none showing as many as those figured in various texts, for example, Jordan's "General Bacteriology" (sixth edition), fig. 69, p. 299, or Migula's "System der Bakterien," vol. 1, pl. 2, fig. 6; vol. 2, pl. 7, fig. 6. Second, the arrangement of flagella is quite variable, often but a single polar flagellum is to be observed, occasionally one or more flagella appear at the sides, and not infrequently individuals occur having two flagella at one pole and with one or two at the sides. Third, there is a marked difference in the shape of the body as compared to those figured by various other investigators. In my preparations, the bodies appear very similar to those stained by ordinary, non-flagella staining methods, and compare very favorably to the figures presented by Migula, fig. 23, p. 727, vol. 2; fig. 6, pl. 7, vol. 2; or Jordan's fig. 68, p. 298. Indeed, if one carefully studies the figures given by these authors of B. typhi, stained by ordinary methods, and contrasts them with the figures given by these same authors, stained by flagella-staining methods, the conclusion is inevitable that either the flagella-staining methods have so distorted the shape of the organisms that they have no resemblance to the true forms, or that entirely different species are involved. The first explanation is probably the true one, for it is well known that many, if not all, of the older flagella-staining methods, such as Loeffler's or Van Ermengem's, possess a marked tendency to distort the bodies, and in addition, to deposit a more or less heavy precipitate on and around the bacteria. This last feature often renders it difficult to clearly delimit a single organism from a clump of organisms. This has been almost entirely eliminated by the method used by the writer, as will be fully illustrated elsewhere. In all probability, then, the explanation for the difference in number and arrangement of flagella of B. typhi found by the writer and that given by various other writers is to be found in the degree of cleanness of preparations, particularly in freedom from deposits. In very few of the published photographs of B. typhi known to the writer can it be absolutely determined whether any one figure represents a single organism or a group of organisms. I am not overlooking the fact that there are other possible explanations, such as differences between strains in the number and arrangement of flagella, and that in making preparations it is very easy to destroy or render unobservable some or all of the flagella. However, the marked success in flagella staining and photographing that I have obtained with numerous and diverse organisms gives me a considerable degree of assurance that in the strains of B. typhi studied the flagella have been properly represented. In view of the importance of any method by which the typhoid fever germ may be accurately identified, the writer will be glad to lend preparations to others who may wish to make comparisons. H. R. ROSEN AGRICULTURAL EXPERIMENT STATION, |