March 25, 1920] 



NATURE 



121 



on aeronautics in connection with the engineering 

 classes at the Universities of St. Andrews, Glasgow, 

 and Edinburgh. The University Court voted a grant 

 of 5oi. to defray the cost of the lectures in Edinburgh, 

 .ind suggested that the lectures should be oi>en to the 

 public. 



M. I'Abbd Breuil, of Paris, has been appointed 

 Munro lecturer on prehistoric archaeology for the 

 academical year 1920-21. 



Liverpool. — The University, through its Chan- 

 cellor, Lord Derby, has just issued an appeal to its 

 constituency, the counties of Cumberland, Lancashire, 

 Cheshire, and North Wales, for funds that will enable 

 it to corhe abreast of present needs. Some of the 

 laboratories have been in existence since 1881, and 

 are obviously inadequate, while all of them are now 

 too small ; thus the practical course in elementary 

 physics is being repeated eleven times each week. 

 The library needs to be extended ; the chemical 

 laboratories are so overcrowded that work is being 

 carried on in Army huts ; new departments are con- 

 templated and interesting developments are being 

 thought out. A chair in the mathematical theory of 

 statistics, a ship-mode! tank, a department of col- 

 loidal chemistry, and a department of marine food 

 industry are among the "futurist" ideas that make 

 this appeal so relevant to a great industrial and 

 commercial centre. It is hoped that the sum of a 

 million pounds may be obtained, and of this about 

 500,000/. is urgently required for pressing expan- 

 sions. .Already about 2oo,oooZ. has been promised. 



On Saturday last, March 20, the third annual dinner 

 of the metallurgy department of the Sir John Cass 

 Technical Institute was held, Mr. G. Patchin, the 

 head of the department, being in the chair. Dr. C. A. 

 Keane, the principal, replying to the toast of the 

 institute, stated that at the present time there are 

 more than a thousand individual students attending 

 the various courses. In 1904 there were three courses 

 and twenty-two students in the metallurgy depart- 

 ment, and this year there are eleven courses and one 

 hundred and twenty students. 



One of the most valuable provisions of the new 

 Army scheme is that which relates to the education 

 of the rank and file. The intention is to provide men 

 in the .Army with an educational training equal, or 

 even superior, to what is available in civilian life. 

 Every officer in command of a company will be held 

 responsible for the instruction of his men, not only 

 in drill and discipline, but also in the class-room and 

 workshop, and the result will certainly be increased 

 intelligence and efficiency. For the introduction of 

 this substantial reform Col. Lord Gorell, who since 

 iqi8 has been Deputy Director of Staff Duties 

 (Education) at the War Office, Sir Henry Hadow, 

 and Mr. P. A. Barnett are largely responsible, and 

 they are to be congratulated cordially that the scheme 

 of Army certificates of education is to come into 

 operation on July i, 192 1. Four classes of certificates 

 are to be awarded on the results of examination. 

 For the third-class certificate candidates must be ible 

 •to read intelligentlv a selected piece of English prose, 

 write a simple letter, work simple suiiis up to and 

 including vulgar fractions in reference to concrete 

 examples, and answer questions on a course of citizen- 

 ship and history. The second-class certificate n^ill 

 apparently require a standard of attainment comparable 

 with those of the former Preliminary Local Examina- 

 tions of Oxford and Cambridge ; and the first class, 

 involving English, mathematics, geography and map- 

 reading, and (optional) an ancient or modern language, 

 approximately that of the First School Examination. 

 NO. 2630, VOL. 105] 



By taking, in addition, two or three single subjects 

 from different groups, a special certificate may be ob- 

 tained. Various practical subjects may be taken for 

 the second-class certificate, and the groups for the 

 special certificate include mechanics, chemistry, physics, 

 botany, zoology, geology, physiology, civil, mechanical, 

 and electrical engineering, agricultural chemistry, and 

 commerce. We shall "watch with close attention ihe 

 application and results of this educational scheme. 



Societies and Academies. 



London. 

 Royal Society, March 11. — Sir J. J. Thomson, 

 president, in the chair. — W. G. Duffield, T. H. 

 Burnham, and A. A. Davis : The pressure upon the 

 poles of metallic arcs, including alloys and composite 

 arcs. In a previous communication (Phil. Trans., 

 A, ccxx., p. 209, 19 19) the authors showed that the 

 poles of a carbon arc behaved as though they repelled 

 one another, and methods were described by which 

 the pressure upon each pole could be measured. 

 Reasons were given for attributing this effect to the 

 reaction consequent upon the emission of electrons 

 from the poles under the influence of thermionic or 

 photo-electric action. The present experiments relate 

 to arcs between iron, copper, and silver terrriinals, the 

 r^te of variation of the pressure with current density 

 being measured for the anodes and cathodes. The 

 pressures were greater than in the carbon arc, that 

 within the copper arc being the largest. Assuming 

 that the pressure is due to the projection of electrons, 

 a comparison between the kinetic energy of the elec- 

 tron and that of the metallic atom at the temperature 

 of the poles showed sufficient agreement to suggest 

 that the electrons before projection were in thermal 

 equilibrium with the metal" of the pole. The reactions 

 upon electrodes composed of an alloy of silver and 

 copper were also measured, likewise "those within an 

 arc between a silver and a carbon pole. In this case 

 the oressure was determined mainly by the material 

 of the pole under examination. The problem of the 

 mechanism whereby a gas may be heated is briefly 

 discussed. Some account is also given of the varia- 

 tion in the potential difference between the poles when 

 the material of one is altered.— J. H. Vincent: Further 

 experiments on the variation of wave-length of the 

 oscillations generated bv an ionic valve due to changes 

 in filament current. Eccles and Vincent have found 

 that in an oscillatorv circuit maintained by a 

 thermionic valve with a grid coil coupling, the wave- 

 length has a maximum value for a certain filament 

 current. This effect is studied further in this paper. 

 In order to varv the filament current, rheostats were 

 designed and used in which the change of resistance 

 was unaccompanied by any sensible change in the 

 self-induction of the filament circuit. The methods of 

 measuring the change of wave-length due to the 

 variation of filament current were different from that 

 emploved bv Eccles and Vincent, but it was found 

 that the results obtained were independent of the 

 particular method bv which the wave-length was 

 studied. It is suggested that changes in several of 

 the variables of a valve-maintained circuit produce 

 effects of the same sitrn on the wave-length and the 

 amplitude of the oscillations. The wave-length and 

 amplitude decrease with the decrease of the grid 

 voltage or of the plate voltage. They also decrease 

 when the coupling of the grid coil with the main 

 oscillator coil decreases. Increasing the resistance in 

 either the condenser branch or the induction branch 

 of the main oscillating circuit lessens the amplitude 

 and wave-length; while altering the filament current 



