It became evident during the War that some men who are organically sound are nevertheless incapable of supporting heavy exertion; and among the older groups that were called to the Colours in 1918 the proportion of such individuals was considerably more. The effect of forcing these men to carry out the duties falling to the lot of an “A” recruit was in many cases harmful to them, and in extreme instances resulted in permanent disability and sometimes in death. The Army Medical Department therefore sought to obtain a method of physical examination, which would supplement the ordinary medical examination of a recruit, and which could be applied to men who proved to be unserviceable material in the hands of the drill sergeant—a test which would, in fact, enable the malingerers to be distinguished from those who were truly incapable of sustained labour.

All methods of vapour density determination hitherto in use, in which quartz or glass manometers are employed, suffer from the disadvantage that the highest temperature attainable is about 750° C.

It is, however, possible to overcome this difficulty whenever the substance under investigation has a considerable vapour pressure below 750° C.

In cases of cleft palate with alveolar fissure, the maxillary bones are, during infancy, not only ununited, but, in general, if not always, more widely separated from one another than in the natural condition. This has been frequently observed in such cases as come under the care of the surgeon, although little attention appears to have been bestowed upon the fact beyond its mere casual mention. Measurements, however, have been lately made by Dr Engel, showing that the difference between certain fixed points—such as the two infra-orbital foramina, the nasal processes of the upper jaw, &c, is very well marked, when the distance is measured in a healthy new-born child, compared with one having a cleft palate.

The location of the trajectory of a charged nuclear particle can be determined by a number of devices whose operation depends on characteristics of gas counters operated in the region of proportional energy response. Such devices have advantages in precision, speed or available size over other types of position-sensitive counters. The events may be located by observing pulses on one of a set of closely spaced anode wires in a common gas volume, by measuring the drift time of primary electrons to a particular anode wire, or by determining the location of an electron avalanche along the length of a single anode. The operation of the different types of systems and the factors affecting their precision are described. Precision to less than 1 mm can be obtained in a number of ways,

The following problem was sent me by Mr Kirkman, F.R.S.; its solution illustrates the Calculus of Relationship, Proc. Roy. Soc. Edinb., vol. xi. pp, 5 and 162:—

Two boys, Smith and Jones, of the same age, are each the nephew of the other; how many legal solutions?

The statements are that Smith is the nephew of Jones, and Jones the nephew of Smith. Let c denote child, then denotes parent, and the equations are

Hence .

The author commenced by stating that although these researches lead him to believe in the existence of two planets revolving in orbits external to that of Neptune, and although there was a great deal of evidence to show that he had actually determined the elements of the orbits, yet the latter point, being dependent on a coincidence of probabilities only, cannot be considered a certainty until the planets are observed.

The author accepts the theory of cometary orbits which supposes that these bodies, wandering through space, are attracted by the sun into the solar system so as to pursue parabolic orbits, and that some of these, in passing a planet, may have their velocity diminished, in which case they will afterwards describe an ellipse in a definite period.

In the paper on this subject, printed in the twenty-sixth volume of the Society's Transactions, the general principles only of this extension were explained; since then the subject has lain aside. An accident has drawn attention to the use of this method for determining cube-roots, and particularly in regard to the duplication of the cube. The consideration of this matter has led to the observation of certain relations which deserve to be recorded.

Whether the variation of resistance in conductors in a steady magnetic field depends on the field strength, on the magnetisation, or on both, does not seem to be definitely settled. The various experimental methods as yet used are fundamentally similar in principle, and have the disadvantage that the experiments are difficult to perform.

A method where the experimental difficulties are very few is to be found in the comparison of the variation of resistance for any given field-strength with some other phenomenon whose dependence on the field-strength or on the magnetisation is already known, and whose exact determination offers no experimental difficulties.

By means of a large quantity of solid carbonic acid, obtained from the University Chemical Laboratory, it was found possible to solidify, and maintain in the solid form for a considerable time, a large mass of mercury. Preliminary experiments made about a year ago, in the usual manner, by means of a triple circuit (iron, german silver, mercury), did not give results of a satisfactory kind. This was apparently due to the difficulty of maintaining steady, or steadily varying, temperatures.

The first obvious difficulty which presents itself, in trying to derive Clerk-Maxwell's equations from those of the elastic-solid theory, appears in the fact that the latter, being linear, do not impose any relations among simultaneous disturbances. Thus, for instance, they indicate no reason for the associated disturbances which, in Maxwell's theory, constitute a ray of polarised light. Hence it appears that we must look on the vectors of electric and magnetic force, if they are to be accounted for on ordinary dynamical principles, as being necessary concomitants, qualities, or characteristics of one and the same vector-disturbance of the ether, and not themselves primarily disturbances. From this point of view the disturbance, in itself, does not correspond to light, and may perhaps not affect any of our senses. And the very form of the elastic equation at once suggests any number of sets of two concomitants of the desired nature, which are found to be related to one another in the way required by Maxwell's equations.

The problem in question is to determine the equation of the curve traced out by any point of an elliptic or hyperbolic disc which touches two fixed rectangular axes. Mechanically constructed figures of different forms of the curve have been given by Tait, who also showed that the same glissette can be traced either by means of an ellipse or a hyperbola. If p, q are the coordinates of the tracing point referred to the axes of the disc as axes of coordinates, the glissette is clearly the θ eliminant of

and Cayley stated that it would be found to be of order 8 in x, y. The actual elimination was first performed by Muir, who obtained in the first instance an equation of order 10. On dividing by an extraneous quadratic factor a lengthy equation of order 8 was obtained; and subsequently Lord M'Laren verified the accuracy of the terms of highest order in this equation.

For purposes of comparison with the analysis of a composite sample of Red Clay recently published in the Proceedings, I have received from Sir John Murray a composite of fifty-two “terrigenous” clays, dredged up from oceanic depths ranging from 140 to 2120 fathoms. In the nomenclature of the Challenger Expedition, forty-eight of the individual samples are classified as “blue muds,” and four as “green muds.” Twenty-three of the clays were collected by the Challenger; the others were brought in from voyages of the Buccaneer, Dart, Egeria, and Rambler. The range of collection, as in the case of the “red clay,” was world-wide, and all of the great oceans are represented in the composite sample.

1. The morphology and anatomy of Trichomanes aphlebioides Christ, a species endemic to New Guinea, is shortly described.

2. The most outstanding feature of the species is the presence of aphlebioid leaves. These latter are shown to be the modified first fronds of the axillary branches.

3. The anatomy of the alphebioid leaves is described. They show great reduction in relation to the humid conditions of the high forests in which the plant grows.

4. The morphology of aphlebiæ and aphlebioid leaves is briefly discussed.

5. No experimental evidence is available with regard to the function of the aphlebioid leaves. Mention is made, however, of the various suggestions which have been put forward in relation to this question.

In his well-known researches on the phosphines, Hofmann has shown (or believes that he has shown) that when an alkyl iodide (or other haloid derivative) is heated with phosphonium iodide and oxide of zinc, primary and secondary phosphines alone result; whereas, when an alcohol is heated with iodide of phosphonium, tertiary and quaternary phosphines are formed exclusively. Thus the two reactions are complementary to each other. Among the series to which he extended his investigations was that of benzyl, and in a paper published in the Berichte of the Berlin Chemical Society he describes the preparation of mono- and dibenzyl-phosphine, and gives their properties. Dibenzyl-phosphine he isolated as a crystalline substance perfectly tasteless and odourless, insoluble in ether, but soluble in alcohol. Its melting-point he found to be 205° C.

A series of reflex adjustments of balance disturbed round the anteroposterior and horizontal axes are described in the domestic duck.

In his memoir of Dr Chalmers, lately read to this Society, Mr Ramsay has referred to an experiment which Dr Chalmers was anxious to have performed on the tide-wave in the Bay of Fundy. The object was to determine the earth's density by the attraction of the tide-wave on a plummet or spirit-level, on the same principle as Maskelyne's experiment on Schiehallion, but with the superior advantages arising from the perfect homogeneity of the attracting mass, and from the circumstance that all the observations might be made at a single station. The experiment might, in short, appear to unite the advantages both of Maskelyne's and Cavendish's methods of determining the earth's density.

THE minor fluctuations of the atmospheric pressure are now engaging the close attention of meteorologists, and my own attention has been drawn to them on account of their connection with the oscillations of lake-surfaces generally known since Forel's investigations under the name of seiches.

As these fluctuations often do not exceed a millimetre or two of water, they are not shown by the ordinary self-registering apparatus. In order to record them we may use a specially sensitive form of barograph, such as the Richard statoscope, which is delicate enough to show these small fluctuations, and yet can be brought back to a momentary zero whenever the indicator threatens to go off the scale or beyond the limits of safety. There are, however, two objections to this method of measurement.

In our last communication (read July 2, 1894) we gave the broad results for three nickel tubes of various bores (see vol. XX. p. 296). In these experiments the screw stopper through which the capillary glass tube passed was made of brass. This brass stopper was used because of the comparative difficulty of working nickel. We were led, in the course of some tentative experiments, to use this brass stopper with one of the steel tubes. Now, in the earlier experiments with the iron and steel tubes, we had used an iron stopper. We were hardly prepared, however, to find that the mere substitution of a brass for an iron stopper should produce such a marked effect, not only on the amount of change of volume in given magnetic fields, but also on the manner in which the volume change varied as the field increased or decreased steadily.

The state of knowledge of fast neutron polarisation due to elastic scattering is reviewed in relation to the optical model of the process. There is clearly a substantial lack of polarisation data at neutron energies and concerning nuclei appropriate to the optical model description. The situation for the extremes of small and of large angle scattering is also considered.