Societies and Academies

Abstract

LONDON. Royal Society, March 25.—E. B. Verney: The secretion of pituitrin in mammals, as shown by per-fusion of the isolated kidney of the dog. When the head and neck of a dog are switched into perfusion-parallel with the isolated kidney, the blood picks up during its passage through the head and neck a substance or substances which inhibit the polyuria of the isolated kidney, augment the urinary chloride output percentually, or sometimes absolutely, and diminish the renal blood flow. This result is still obtained after previous exposure of the pituitary body. It does not occur as the result of perfusing the pelvis and lower limbs in parallel with the kidney. Previous removal of the pituitary body abolishes the reaction. An antidiuretic, chloride - augmenting, and vasoconstrictor principle or principles are contributed by the pituitary body to blood during its passage through the head of a dog.—H. W. Florey and H. M. Carleton: Rouget cells and their function. Capillaries in cat's mesentery have been studied by a method which enables blood-vessels to be selectively stained by intra-arterial injection of fixative and stain. Morphologically definable Rouget cells cannot be identified. In vivo, capillaries reacted to mechanical stimuli and particularly to the action of histamine and pituitrin. While capillaries are capable of actively expanding and contracting, their motor activities reside, not in Rouget cells, but in the endothelial elements.—R. M. Sargent: The relation between oxygen requirement and speed in running. A modification is described of the usual method of determining energy expenditure during running. The subject does not wear a mouthpiece, or carry a Douglas bag, and the exercise can take place under natural conditions. The results show actual energy expenditure and that involved in ‘start’ and in ‘pull-up’ For the subject of these experiments to run 120 yards in 13 seconds necessitated an energy expenditure equivalent to an oxygen requirement of 29 litres per minute, or to 13.7 horse-power. There is extreme energy cost for rapid and vigorous exercise of short duration. An approximate means of allowing for energy utilised in ‘start’ and in ‘pull-up’ is adopted. Then the general relation between speed in running and oxygen requirement is: Oxygen requirement per 120 yards increases about as the 2.8th power of speed. Oxygen requirement per minute increases approximately as the 3.8th power of speed. The calculated optimum performances agree well with those actually recorded (or estimated) by the subject, over the range 300 yards to 2 miles.— Seana King: Oogenesis in Oniscus Asellus,—J. L. Synge: On the geometry of dynamics. The representation of configurations by points of multi-dimensional Riemannian space has been used hitherto to discuss certain aspects only of classical dynamical theory. In the present paper, tensor notation is used throughout, and to the advantages of this notation the novel results are due. Parallel discussions are given corresponding to two line-elements - the ' kinematical' line-element, ds* = 2Tft2 = amndqmdqn, and the ' action' line - element, ds* = 2 (h - V) Tdt2 = (A - V) amnd f"dq". The laws of motion are discussed, leading to a generalisation of Bonnet's theorem on particle orbits and a geometrical elucidation of the Principle of Least Curvature. A completely determinate form of the Lagrangian equations for non-holonomic systems is developed. Necessary and sufficient conditions are obtained for the admissibility of (N-i) ignorable co-ordinates in a system with N degrees of freedom. From an invariant geometrical definition of stability three special types of particular dynamical importance are selected. A new definition of steady motion is given. The system of normals to a curve, originally defined by Blaschke, plays a fundamental part.- P. E. Shaw and C. S. Jex: Tribo-electricity and friction.-H. G. de Laszlo: The absorption-spectra of some naphthalene derivatives in vapour and solution. The ultra-violet absorption spectra of mono-derivatives of naphthalene containing the groups CH3, Cl, Br, OH, COOH, CN, and NH2, were measured in vapour and in hexane solution. The /3-isomer spectra are more like that of naphthalene than the a spectra. All were shifted towards the red when compared with naphthalene by an amount which is of the same order in the case of naphthalene and benzene derivatives containing the same group. The solution spectra are always shifted towards the red when compared with the vapour. This shift varies with the group, suggesting a modified "Stark effect "when the dipolar molecules are in the strong electric field of the solvent. The bands of most of the bodies examined have been ranged in simple series. These periodicities, representing the atomic oscillations, are all smaller than that of the parent body and appear again in the infra-red.-O.Maassand W. H. Barnes: Some thermal constants of solid and liquid carbon dioxide.-R. H. Fowler and D. R. Hartree: An interpretation of the spectrum of ionised oxygen (O II). The terms of the 0 II spectrum deduced from the observed lines by A. Fowler are correlated with theoretical terms expected on the theory of complex spectra developed by Heisenberg and Hund. The general agreement is satisfactory. No lines involving the deepest-lying terms have yet been identified, but from consideration of the O I spectrum it appears likely that the normal term of the O II spectrum is a quartet S term.--G. C. Simpson: On lightning. The conducting channel of a lightning flash originates in the region of maximum electric field and develops only in the direction of the seat of negative electricity. A negatively charged cloud can only be discharged by a discharge originating in a positively charged cloud, or in the induced positive charge on the earth's surface. A positively charged cloud may be discharged by discharges starting in the cloud and terminating either in the surrounding air or on the earth's surface. If a lightning flash is branched, the branches are always directed towards the seat of negative electricity. The application of these conclusions to 442 photographs of lightning discharges reveals the fact that the majority of lower clouds from which discharges proceed are positively charged.