Societies and Academies

Abstract

LONDON. Royal Society, May 8.—Sir Archibald Geikie, K.C.B., President, in the chair.—A. D. Waller: The various inclinations of the electrical axis of the human heart. This paper is in substance the direct continuation of a communication made to the society in 1889 (Phil. Trans., p. 169), in which it was shown (i) that the electrical effects accompanying the beat of the human heart can be demonstrated and studied by “leading off” from the mouth and from the extremities; and (2) that in consequence of the oblique situation of the heart in the thorax these “leads” are to be classified as favourable and unfavourable or strong and weak. Of the six possible leads from the four extremities, three are strong (transverse, axial, right lateral) and three are weak (inferior, equatorial, left lateral). Of the four possible leads from the mouth and one extremity, one is weak (right superior) and three are strong (left superior, right and left inferior). The electrical equator is an imaginary line of zero potential across the chest from left shoulder to right side. The electrical current axis is from right shoulder to left side, at right angles to the equator.—Surgeon-General Sir D. Bruce, Majors D. Harvey and A. E. Hamerton, and Lady Bruce: Trypanosome diseases of domestic animals in Nyasaland. III., Trypanosoma pecorum.—T. Goodey: The Encystation of Colpoda cucullus from its resting cysts and the nature and properties of the cyst membranes. The ectocyst ruptures and sets free the transparent endocyst. Both ectocyst and endocyst are composed of carbohydrate substances and are resistant to acids, weak alkalies, and many other reagents; failing to give any reaction with iodine in potassium iodide solution. The endocyst is composed of a new carbohydrate for which the name Cystose is proposed. During encystation the endocyst wall is digested by a powerful enzyme secreted by the enclosed organism, and by this means the latter is enabled to escape. The name Cystase is proposed for this enzyme.—C. Shearer, W. De Morgan, and H. M. Fuchs: The experimental hybridisation of Echinoids.