Societies and Academies

Abstract

LONDON. Royal Society, January 31.—Sir J. J. Thomson, president, in the chair.—A. Mallock: The growth of trees. An account is given of some recent observations of the growth of trees. The observations consisted in the measurement, at short intervals of time, of the variation of the girth of the trees at a height of 4 ft. or 5 ft. above the ground. The measures were made by an “interference” method, which is described. The results showed a well-marked daily period in the variation of girth, different for different species of tree, but in all cases having a maximum at night and a minimum shortly after noon. Diagrams of sets of observations, each extending over several days, are included, showing the growth of a black poplar, an oak, and a Douglas fir. From twenty to thirty readings were taken in the course of each twenty-four hours.—Prof. B. Moore and T. A. Webster: Action of light rays on organic compounds and the photosynthesis of organic from inorganic compounds in presence of inorganic colloids. The results are recorded under three sections:—(a) Photosynthesis by inorganic transformers; (b) action of sunlight and of ultra-violet light upon concentrated solutions of formaldehyde; (c) the general formation of formaldehyde by the action of light upon organic substances of biochemical origin. In the concluding section a general reversible reaction is described as a result of which formaldehyde rises in all intense reactions of light upon substances of biochemical origin. This reaction in presence of excess of light is an interesting reversal of the process by which all organic matter has been built up from inorganic sources. The bearing of this process upon the germicidal action of sunlight, and upon the destruction of living organisms by ultra-violet light, is discussed, and it is pointed out that the simple organic products so formed are incompatible with the life-processes of living organisms and so lead to their destruction. Taking such a reaction as travelling in the reverse direction, it is shown that the building up of organic matter from inorganic must have been a necessary precedent to any existence of living organisms on the earth, and that all accumulations of reduced substances possessing stores of chemical energy must have arisen in this manner from storage of the energy of sunlight.—Capt. W. J. Tulloch: The isolation and sero-logical differentiation of Bacillus tetani. (1) More than one variety of non-toxic endosporing bacillus resembling B. tetani in morphological characters can be recovered from wound-exudates in cases of the disease. (2) There are at least three different types of toxic B. tetani. (3) The “U.S.A. type” of the bacillus that commonly used for the preparation of antitoxin is not frequently obtained from wound-exudates in cases of the disease occurring among men who have received prophvlactic inoculations of antitetanic serum. (4) Culture in a selective medium, followed by agglutination of the washed growth, in presence of the three-type sera, gives valuable information. It is, however, apparently not so delicate a test.for the presence of B. tetani as is animal inoculation after culture of the wound-exudate.—Dr. J. Brownlee: An investigation into the periodicity of measles epidemics in the different districts of London for the years 1890-1912. In a previous paper it was found that during the years investigated the chief epidemic periodicities were respectively 87, 97, 109J, and 114 weeks, the most marked period being that of 97 weeks. It is found now that the epidemic with the 87 weeks' period occurs solely south of the Thames, where it is a very marked phenomenon; that the epidemic with the 97 weeks' period, while very marked in the whole of London, is especially marked in the western district; that the epidemic with the 109J weeks' period is present throughout London with the exception of the east, but is most marked in the western districts; while that with the 114 weeks' period is most marked in the central districts and least present in the eastern districts. The most important fact found, however, is that the epidemics of different periods have special phenomena of their own. In the case of the chief period, that of 97 weeks, the epidemic practically breaks out synchronously in the whole city. In the case of the epidemic with the 87 weeks' period a quite different phenomenon is found, the permanent seat of this epidemic being St. Saviour's or Bermondsey, whence the disease spreads to the neighbouring districts. With regard to the period 109 weeks, there is evidence that, in both, the conditions just described exist, this epidemic breaking out synchronously in several districts and extending from these to neighbouring districts.