June 8, 1916] 



NATURE 



0»D 



of hard and soft aluminium. It was found that the 

 specific heat of the hard aluminium was higher than 

 for annealed, and this confirmed the view that 

 aluminium is converted into an amorphous form by 

 excessive mechanical work. It was further found 

 that the specific heat underwent a change when the 

 hard-drawn bars and wire were heated to ioo° C— 

 Dr. R. Seligman and P. Williams : Note on the anneal- 

 ing of aluminium. Hard-worked aluminium which 

 had been heated for ten hours at 125° C. was less 

 readilv soluble in nitric acid than the same metal 

 before heating, but if the heating were continued for 

 eighty hours, this comparative immunity from attack 

 was lost (see p. 310).— E. J. Hartung : Contribution to 

 the theorv of solution. The author has tested the 

 divergence in phvsical properties from those calculated 

 bv the simple mixture" law shown by two completely 

 niiscible liquids which do not visibly react with each 

 other. No simple solvate theory- will suffice to explain 

 the experimental results, even though the liquids uSed, 

 with one exception, are little associated. 



Physical Society, May 12. — Prof. C. V. Boys, presi- 

 dent, in the chair.— Dr. H. S. Allen : The latent heats 

 of fusion of metals and the quantum-theory. The latent 

 heat of fusion is identified with the energ>' necessary to 

 counterbalance that of a certain number of "oscilla- 

 tors" concerned in holding together the crystalline 

 structure. Assuming that the energy of an oscillator 

 having a vibration frequency v is 



RTx 



^-1 



where -v stands for liv/RT, it is found that the atomic 

 heat of fusion of a metal can be calculated with fair 

 accuracy by the formula, 



AL=rNRTx *' . 

 e^- 1 



Here A denotes the atomic weight, L the latent heat, 

 and c the ratio of the number of oscillators in ques- 

 tion to the number of atoms. Thus, the number of 

 oscillators in one gram molecule is Nc, where N is 

 Avogadro's constant. It is found that to the factor c 

 must be assigned a value which is either unity or a 

 simple fraction. The frequency at the temperature of 

 the melting point is calculated by means of the 

 formula of Lindemann. The application of Debye's 

 theor>^ is also discussed. — T. Smith : [.enses for light 

 distribution. The principle on which lenses lor secur- 

 ing a required distribution of light from a given source 

 have been designed is illustrated by a two-dimensional 

 example. The principle employed is to divide the 

 incident and emergent energy into a number of equal 

 parts, and compute the lens system so that the rays 

 which separate off these portions of incident light from 

 one another are refracted as rays which separate the 

 corresponding portions of the emergent light. The 

 surfaces obtained are in general of varying cur\'ature, 

 and the lenses must, therefore, be moulded. It is 

 shown how the effect of the finite size of the light 

 source may be determined. — T. Smith : The choice of 

 glass for cemented objectives. The strict fulfilment 

 of the mathematical conditions for freedom from 

 colour, spherical aberration, and coma, for objects at 

 varying distances from a thin cemented doublet lens, 

 necessarily demands a change in the kinds of glass 

 as the position of the object is changed. The paper 

 describes a method by which the proper glasses can 

 be determined bv using a ^lass chart on translucent 

 paper, in conjunction with diagrams calculated for the 

 purpose, as a slide-rule. 



Zoological Society, May 23. — Dr. Henry Woodward, 

 vice-president, in the chair. — Lieut. R. Broom : 

 The structure of the skull in Chr\'sochloris. 

 Two stages in the development of the skull have been 



NO. 2432, VOL. 97] 



studied. The earlier is that of a newly born Chryso- 

 1 chloris hottentota, the skull of which has been cut into 

 ; microscopic sections and reconstructed, and a some- 

 I what later stage of Chrysochloris asiatica, the skull 

 I of which has been prepared for the study of the mem- 

 ! brane-bones. The skull is held to be in some respects 

 I highly specialised, and in others degenerate, although 

 ! also retaining a number of very primitive characters. 

 — Dr. C. W. Andrews : An incomplete sternum of a 

 I gigantic carinate bird from the (?) Eocene of Nigeria. 

 i Comparison with the sterna of several groups of birds 

 ! leads to the conclusion that this specimen, though 

 ' differing considerably from the sternum of any living 

 I member of the group, belonged to a very large repre- 

 \ sentative of the Tubinares. It has about twice the 

 linear dimensions of the sternum of an albatross, of 

 which the spread of wing (in the flesh) was 10 ft. 8 in. 

 It is proposed to refer this species to a new genus 

 Gigantornis, the specific name being G. eaglesomei. 

 , after its discoverer. — Dr. A. Smith Woodward : A 

 ■ mammalian mandibular ramus from an Upper Creta- 

 ceous formation in Alberta, Canada. The specimen 

 represented an opossum-like marsupial, and the author 

 referred it to a new species of Cimolestes, named C. 

 cutleri, in honour of its discoverer, Mr. W. E. Cutler. 

 The close dental series behind the canine measured 

 30 mm. in length, and the molars differed from those 

 of the two known species of the genus in their rela- 

 tively less elevated trigonid. The fourth premolar 

 ; was a large, tumid, laterally compressed cone, with 

 one well-separated posterior cusp. — V. Lutshnik : (i) A 

 list of Carabidae collected in Chopersk district. South 

 Russia ; (2) a new species of the genus Platysma from 

 China ; and (3) notes on species of Platysma from 

 Australia.— E. G. Boulenger : A new lizard of the 

 genus Phr}-nosoma. — Dr. R. W. Shnfeldt : Notes on 

 ; cases of albinism seen in American animals. 



P.ARIS. 



I Academy of Sciences, May 22. — M. Camille Jordan in 

 the chair. — G. Bigourdan : The immediate collabora- 

 ' tors of Peiresc. These included Jean Lombard, 

 ' Simon Corberan, and Antoine Agarrat, and an outline 

 of the astronomical work of each is given. — E. Cahen : 

 The general reduced numbers of Hermite. — ^T. 

 Bialobjeski : The influence of the pressure of radiation 

 on the rotation of the celestial bodies. — T. Peczalski : 

 The effect of temperature on the structure of paraffin. 

 A study of the effects produced on paraffin wax by 

 prolonged exposure to temperatures slightly below its 

 melting-point. For a paraffin wax the density of 

 which was originally below 0900 the density increased 

 with prolonged heating, and this change is accom- 

 panied by a considerable reduction in the electrical 

 conductivit}- of the material. — M. Siegbahn : The exist- 

 ence of a new group of lines (series M) in high- 

 frequencv spectra. The lines were produced by 

 uranium. On account of the absorption of these lines 

 bv air the spectrograph was in a vacuum, the crA'stal 

 used being a plate of gypsum. . This series has also 

 been found to be represented in the spectra of thorium, 

 bismuth, lead, thallium, and gold. — A. Schidlof and A. 

 Targonski : The Brownian movement of particles of 

 oil, tin, and cadmium in different gases and at 

 different pressures. From the results obtained ex- 

 perimentally it is, concluded that Einstein's theon.- of 

 Brownian motion applies to all spherical particles 

 without restriction. It also applies to non-spherical 

 particles of not too irree^ular form, whatever mav be 

 the gaseous medium. — F. Pisani : A new method for 

 the estimation of fluorine. The method is based on 

 the insolubility of thorium fluoride in solutions faintly 

 aridified with acetic or nitric acid. 001 per cent, of 

 fluorine can be detected. The application of the 

 method to various minerals containing fluorine is 



