The analogies between the two Kingdoms of Living Organisms are so numerous that in many ways the study of the one may be rightly held to illuminate that of the other. Provided the lines of comparison be broad enough, good may come from following out such analogies. But whenever the comparisons are more closely drawn they should be examined critically: and in any case nothing more than analogy can be postulated for any comparison relating to their advanced types.

According to Sommerfeld's theory of the fine structure of spectral lines, the magnitude of the separation of the doublets for all the members of the Balmer series of hydrogen should be constant, and have a value of 0·365 cm.−1. Now, owing to the extreme lightness of the hydrogen atom, a direct proof of Sommerfeld's theory by observation of the hydrogen lines is a somewhat difficult undertaking. At ordinary temperatures the Doppler effect is considerable, so that the lines are broadened out and the components of the doublets tend to overlap. The atom of helium, however, is four times as heavy as that of hydrogen, while the nuclear charge is double, so in consequence the separation of the doublets should be, according to the theory, sixteen times as great.

In the Quarterly Journal, No. 162, 1910, Professor A. R. Forsyth considered some of the problems arising from a homographic transformation of plane curves whose equations could be written in the form

where F is a rational integral function of z and z′, and where z = x + iy, z′ = x − iy determine the rectangular Cartesian coordinates of the plane. It was suggested that the theory could be developed algebraically by using the symbolic methods of the German school which proved so powerful in furthering the theory of binary forms.

Nettles of the two species Urtica dioica and Urtica urens are commonly infested with the aphid Macrosiphum urticæ, and amid the living aphids and a collection of moulted skins dead examples are almost certain to be found. These dead aphids are almost spherical in shape and are of a brown colour, quite different from the colour of a normal aphid. They are attached to the nettle-leaf, often to the upper surface, by their ventral side, the leaf generally being discoloured at the point of attachment. If a number of these dead aphids are collected it will be found that, after a time, hymenopterous parasites, a species of the family Braconidæ, issue from the swollen body of the dead aphids. This parasite has been identified as Aphidius avence (Hal.), and the present paper deals with the life-history and habits of this species.

Sir J. J. Thomson has shown that if two atoms combine, consisting of electrons round positive nuclei, the arrangement of the two combining electrons is as shown in the following figures, the two electrons taking up a lateral position and being both attractedby the +ve nuclei, A and B.

If, on the other hand, the electrons are replaced by magnetons, it has apparently been assumed that the two nearest magnetons on the approaching atom will mutually attract each other, and rotate to face each other, taking up a position as shown in the following diagram.

It is proposed to investigate the various ways in which it is possible to divide the plane into congruent triangles, and space of three dimensions into congruent tetrahedra. The method of inquiry will not at first reveal any distinction between elliptic, euclidean, and hyperbolic space; networks in all three spaces will be obtained concurrently, and they must be tested afterwards to determine the type of space to which they belong. In the first part we shall deal with the plane, and in the second part with space of three dimensions.

In my Presidential Address of October 1920 I cited the stems of certain Zygopterideæ in illustration of size as a factor in Stelar Morphology. But only a few salient facts were adduced from the protosteles of their stems. The relation of increasing size to the elaboration of the vascular tracts of primitive plants deserves further examination: and the results would appear the more cogent if the evidence were collected not only from series of plants which are related to one another, or even from different parts of the same plant, but also from series not so nearly related. A re-examination of the published figures of axial steles and petiolar traces in the fossil Cœnopterideæ has provided interesting results.

In the period which we have now reached the interest taken in the study of Alternants shows comparatively little sign of slackening, especially if the years given over to the War be taken into account. Close on fifty (50) writings, in six different languages and of various degrees of importance, fall to be considered.

One noteworthy feature of the collection is the exceptional number of the papers occupied with the investigation of Symmetric Functions: approximately a third of the whole may be so classified. It is also somewhat striking in connection therewith to note that this body of work has two quite independent sources, the one centring in a small East-Prussian town, the other confined mainly to a busy city in the State of New York.

The result of the Michelson-Morley experiment was unavoidably revolutionary. The idea of an æther, through which optical effects were propagated with finite though great velocity, had grown up gradually, and had been rendered almost certain by the experimental establishment of the wave theory of light. Even on gravitational grounds, Newton himself regarded the existence of an æther as essential. Yet, in most relativistic discussions which deal with the point, he is relegated to the ranks of the direct actionists. His own words were emphatic. He said that, in his view, no one who was competent in matters of philosophic thought could be an advocate of distance action.

A clock pendulum and movement have been designed which are never actually connected either mechanically, electrically, or magnetically, yet the movement drives the pendulum and the pendulum controls the movement. The usual “escapement” has been eliminated.

The clock has been made and tested; first in the form of a regulator, and then in the form of a heavy turret clock with triple worm gearing to the hands.

The power is derived from an electric motor in continuous motion; this raises a gravity arm which, in descending, drives the pendulum with a constant force. The motor also drives the clock hands, makes contacts to drive other dials, and may drive telescopes, chronograph drums, etc. After acting on the pendulum the gravity arm is arrested by a stop, and electric power passes to the motor while arm and stop are in contact. Current is interrupted when the motion of the motor raises the gravity arm. The speed of the motor is governed by the time of contact, but the motion of the motor is maintained between the periods of contact by a reduced current and by kinetic energy. Application has been made for a patent.

This communication describes a series of experiments carried out at the Heriot-Watt College, Edinburgh, on behalf of the Oxygen Research Committee, Scientific and Industrial Research Department. The experiments may be regarded as continuing a line of inquiry introduced by a paper read before the Society in 1921; their aim was to obtain data in regard to the rate of decay of the vacua (i.e. the rate of increase of the pressure in the vacuum envelope) of metallic Dewar vessels.

It is proposed in this paper to examine the forms obtainable for ds2 in Weyl's generalisation of Einstein's Theory of Relativity, when an isolated electron, considered as a spherical entity carrying a uniform surface distribution of electricity, is present. The problem of the electron on Einstein's theory has been discussed by Nordström (Verslag. Ak. Amsterdam, January 1918). W. Van Der Berg (Vraagstukken mit Einstein's gravitatic theorie, Harlem, 1920) has given an approximation to the solution which has been obtained exactly by H. Vanderlinden (Bull. Acad. Roy. de Belgique, May 1921).

One of the outstanding problems of physics at the present time is that of finding an explanation of chemical combination. Sir J. J. Thomson has done much to bridge the gap between chemistry and physics by attempting to extend the electronic theory of matter so as to explain how atoms may be linked together to form the stable system which constitutes a molecule. To avoid the difficulties inherent in the view that the electrons are describing orbits under forces varying rigorously as the inverse square of the distance, he assumes that the electrons take up definite equilibrium positions under their mutual repulsions and forces exerted by the positive charges. Equilibrium is secured by postulating in the latter case a more complicated law of force than the inverse square, so that the attraction between an electron and a positive charge changes to repulsion at a certain distance.

It has long been known that yellow phosphorus is slowly oxidised in air at the ordinary temperature and that the oxidation is accompanied by a glow easily visible in a darkened room. If oxygen at atmospheric pressure is substituted for air no glow is perceived, and the oxidation, if it occurs at all, is incomparably slower than in air. If the pressure of oxygen is reduced either directly or by admixture with an indifferent gas the glow may be made to reappear. The seeming contradiction of the law of mass action involved in these phenomena has been the subject of many experiments, and the main object of the present investigation is to attempt to throw some light on this anomaly.

In a previous article a new method of investigating colour blindness has been described, together with its application to twenty-three cases. These were all congenital cases, and it was thought desirable to find what results the method gave when applied to cases of colour blindness caused by disease. With this purpose the apparatus was removed to the Eye Infirmary in Charlotte Street, and some of the cases that presented themselves there investigated.

The monumental work of the late Sir John Murray and Dr Renard on the examination and classification of deep-sea deposits has left little to be desired either as regards methods or results. There was, however, one respect in which they were handicapped—no satisfactory method was known of ascertaining the distribution of sizes of the particles of which a sample was composed.

In 1915 Dr Sven Odén of Upsala made known a method of soil analysis whereby he obtained by a sedimentation process data from which he could construct the distribution curve representing the relative proportions of particles of various sizes. He later obtained from the Challenger Office several samples of different types of deep-sea deposit which he subjected to the same form of analysis.

Sir A. Ewing in his paper, “On Models of Ferromagnetic Induction,” has suggested that there is something in the atom which turns in response to an applied magnetic field.

In discussing the above it was suggested by Professor Barkla that it would be a matter of interest to study the X-ray corpuscular emission from iron when magnetised and unmagnetised, especially under the influence of very penetrating rays.