December 13, 1917] 



NATURE 



299 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 

 The geophysical discussions arranged by the Geophys- 

 ical Committee of the British Association on November 

 7 and December 5 were well attended and very success- 

 ful. The meetings will begin again in February, and 

 will continue until June inclusive. At the February 

 meeting Dr. A. Strahan will be in the chair, and the 

 speakers will be Col. Close, on the effect of variation 

 of barometric pressure on mean sea-level, and Major 

 I lenrici, on precise levelling. At the March meeting 

 Sir Napier Shaw will be in the chair, and Prof. H. H. 

 Turner will open a discussion on seismology, in which 

 ic is expected that Mr. G. W. Walker and Mr. R. D. 

 Oldham will take part. 



Mr. Bertkand Russell's lectures on the " Philo- 

 .>ophy of Mathematics," at Dr. Williams's Library, 

 Gordon Square, W.C.i, have been so successful that a 

 second course, to be given after Christmas, has now 

 been arranged. The new course will be quite distinct, 

 and, like the present, will be designed to expound the 

 logical basis of mathematics. The lectures presuppose 

 no special mathematical training, and technical terms 

 and symbols are dispensed with. The present course, 

 which concludes on December 18, has dealt with the 

 more specially mathematical questions. The new 

 course will be devoted to philosophical problems, and 

 Mr. Russell will expound his theory of logical atomism. 

 The lectures are on Tuesday evenings at 5 o'clock; 

 they will begin on January 22. 



Mr. Asquith, in his address in the Town Hall, 

 Birmingham, on Tuesday, December 11, at a meeting 

 promoted by the National War Aims Committee, re- 

 ferred to problems of reconstruction, and is reported 

 by the Daily Telegraph to have said : — " In regard to 

 these matters, you will not be surprised if I put in 

 the forefront, as of paramount importance, a compre- 

 hensive rebuilding, and a far more adequate equip- 

 ment, from the very bottom to the very top, of our 

 system of national education, of w-hich the Bill intro- 

 duced by Mr. Fisher gives the hope, and, indeed, the 

 promise. To put it from the lowest and most material 

 point of view, it is largely, indeed mainly, through our 

 educational deficiencies that we have either lost or 

 never established some of those basic industries which 

 no great country can afford to be without. The future 

 relations of employers and employed will have to be 

 readjusted, starting from the proposals, which I believe 

 to be in spirit and principle almost universally accepted, 

 of the Whitley Report, with developments for securing 

 greater elasticity, more representative authority, and a 

 more vital contact with new conditions, in the organisa- 

 tion of both; and, above all, with the purpose of 

 achieving for men, women, and children opportunities, 

 which were never given them under the old factory 

 svstem, for a freer, a more self-developed, a humaner 



SOCIETIES AND ACADEMIES. 

 London. 

 Royal Society, December 6.— Sir J. J. Thomson, presi- 

 dent, in the chair.— Prof. W. H. Young : The series of 

 Legendre. — L. Hartshorn : The discharge of gases under 

 high pressures. It is well known that when gas dis- 

 charges through an orifice from a vessel in which the 

 pressure is />„ into one in which it is />,, the rate of 

 discharge is approximately constant from pi = o up- 

 wards to some critical value, but then, as />, further 

 increases, the discharge falls off, slowly at first, after- 

 wards with greater rapidity. In the present investi- 

 gation, this phenomenon is examined with greater 

 accuracy than has hitherto been obtained. In every 

 NO. 251 1, VOL. 100] 



case it was found that the flow was constant to at 

 least one part in 10,000 for a considerable range of pi. 

 The critical value of pi, at which the flow began to 

 change, varied widely for different nozzles, being 

 about 0-2 pg for the convergent and parallel ones, but 

 as high as 07 />„ for certain divergent ones. Thus, the 

 theoretical value for convergent nozzles, viz., 0-527 p^, 

 cannot be accepted as applying even approximately to 

 all nozzles.— Lt.-Col. A. G. Hadcock : Internal ballistics. 

 This paper deals with the burning of the explosive in 

 the gun and the expansion of the gas, both before and 

 after the charge has been consumed. On firing the 

 gun the action is threefold : — (i) The driving band on 

 projectile is forced into the rifling grooves. (2) In 

 subsequent burning of charge, the gas from any frac- 

 tion of charge expands with consequent reduction 

 of temperature. The still burning powder gives addi- 

 tional heat. The expansion is thus partly adiabatic 

 and partly isothermal. (3) After the charge is con- 

 sumed the gas expands adiabatically. From expres- 

 sions given in the paper, and knowing the rate of burn- 

 ing of cordite under various pressures, formulae are 

 developed for finding velocity of projectile, position in 

 gun, and pressure of gas. The magnitude and position 

 of maximum pressure are found by a further develop- 

 ment of formulae. — Dr. A. Russell ; The electrostatic 

 problem of a conducting sphere in a spherical cavity. 

 The author gives formulae by means of which the 

 capacity, the electric force between the spheres, and 

 the maximum electric stress on the dielectric between 

 them can be readily computed in all cases to any 

 required degree of accuracy. The solutions of these 

 problems are required when determining the ratio of 

 the measure of the electrostatic to the electro- 

 magnetic unit of charge by means of a spherical 

 condenser for the calibration of a spherical 

 condenser of variable capacity, for the calibra- 

 tion of a high-tension voltmeter, and for the 

 determination of the electric strengths of insulating 

 materials.— Prof. G. N. Watson-. The zeros of Bessel 

 functions. The paper contains a statement and discus- 

 sion of some general theorems concerning the zeros of 

 Bessel functions ; the theorems are true for functions 

 of any order, and, unlike results previously known, 

 are of particular interest in the case of functions of 

 high order. It appears that comparatively general con- 

 siderations of a non-arithmetical type yield fairly pre- 

 cise information concerning the position and numbers 

 of the zeros of the Bessel functions of the first kind. 

 It is doubtful whether results of this character could 

 be obtained without making use of the method of 

 steepest descents which has been prominent in various 

 recent investigations. 



Aristotelian Society, December 3. — Dr. H. Wildon 

 Carr, president, in the chair.— F. C. Bartlett -. The de- 

 velopment of criticism. An attempt to trace broadly 

 the development of criticism reveals four main stages — 

 the simply appreciative, the conventional, the rational, 

 and the intuitional. At the first, criticism is the imme- 

 diate outcome of the feeling accompanying ease or 

 hesitation of reaction ; at the second, a situation or 

 object is criticised by virtue of its relation to a mass of 

 preceding experience, the latter remaining relatively 

 vague and unanalysed; at the third, definite rules of 

 criticism arc developed; at the fourth, the verdict passed 

 is regarded as the outcome, on one hand, of the pecu- 

 liar nature of the object, and, on the other, of the 

 relation of the object to the critic. Affective factors 

 play a dominant part throughout in the production of 

 criticism, while the direction of development is deter- 

 mined bv a persistent "effort after meaning." 



Mathematical Society, December 6.— Prof. H. Hilton, 

 vice-president, in the chair. — Col. R. L. Hippisley : A 

 new- method of describing a three-bar curve. — O. 



