August 20, 1908] 



NA TURE 



38: 



ipii-it, and insists on the necessity of ttie latter as the 

 foundation for those powers of initiative and of intelligent 

 activity without which progress is impossible. Prof. 

 Appell points out that the object of higher education is 

 three-fold — to make, to teach, and to apply science — and 

 considers in detail how far the educational system of France 

 attains these objects. He finds much overlapping, and 

 directs special attention to the large amount of teaching 

 of pure science which goes on in technical schools the 

 principal function of which, he urges, should be to teach 

 technical applications to pupils already well grounded in 

 science at the universities or other schools of university 

 ivpe. Those interested in higher education in this country 

 will find much food for thought in Prof. Appell's address, 

 and many will ask, Are our institutes for higher educa- 

 tion carrying out their duty of making science as they 

 ought? while more will want to know how much of the 

 energy of our polytechnics and technical schools is devoted 

 to teaching pupils the laws of motion or how to solve 

 simple equations. 



The latest article of a series published by the Times on 

 American life is devoted to " Colleges and Character." 

 After mentioning the rapid growth of the universities, 

 which in 1904 already had 119,496 undergraduates, the 

 writer agrees with the Rhodes scholar who reported that 

 from the sole standpoint of scholarship it was not necessary 

 for him to leave America. On the other hand, the author 

 of the article lays blame on the " elective " system, which 

 presupposes that the average youth of eighteen, fresh from 

 school, has defined aptitudes, understands fiimself, has 

 adequately given shape to his ultimate purpose, and can 

 be depended upon to select the studies best adapted to the 

 achievement of his destiny. Nevertheless, he considers 

 that the fundamental idea of electives is sound, but that 

 the reaction from the old rigid courses of instruction has 

 gone too far. A student may graduate by passing in 

 four entirely disconnected subjects in each of four successive 

 years; moreo\sr, there is a temptation to seek "soft 

 options." On the other hand, we may observe that it is 

 commoner in America to find commercial men who, by 

 pursuing the somewhat haphazard sampling of studies 

 which the elective system permits, have acquired intelligent 

 appreciation of, say, comparative religion and Rontgen 

 rays. In England men of the same class rarely attempt 

 any university study. The author expects that " electives 

 will never be disallowed in the future, but will be intelli- 

 gently restricted, so as to secure that all students — not 

 merely such as choose — will be subjected to the discipline 

 proper to university life on its intellectual side. 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, June iS. — " An Electrical Method of Count- 

 ing the Number of a Particles from Radio-active Sub- 

 .stances. " By Prof. E. Rutherford, F.R.S., and Dr. H. 

 Ceiger. 



(i) By employing the principle of magnification of 

 ionisation by collision, the electrical effect due to a single 

 a particle may be increased sufficiently to be readily 

 observed by an ordinary electrometer. 



(2) The magnitude of the electrical effect due to an a 

 particle depends upon the voltage employed, and can be 

 \'aried within wide limits. 



(3) This electric method can be employed to count the 

 a particles expelled from all types of active matter which 

 <'mit a rays. 



(4) Using radium C as a source of o rays, the total 

 number of o particles expelled per second from i gram 

 of radium have been accurately counted. For radium in 

 equilibrium, this number is 3-4Xio'° for radium itself and 

 for each of its three a-ray products. 



(5) The number of scintillations observed on a properly 

 prepared screen of zinc sulphide is, within the limit of 

 fxperimental error, equal to the number of a particles 

 falling upon it, as counted by the electric method. It 

 follows from this that each o particle produces a scintilla- 

 tion. 



NO. 2025, VOL. 78] 



(6) The distribution of the o particles in time is governed 

 by the laws of probability. 



The authors have previously pointed out that the principle 

 of magnification of ionisation by collision can be used to 

 extend widelv the already delicate methods of detection of 

 radio-active matter. Calculation shows that under good 

 conditions it should be possible by this method to detect a 

 single j3 particle, and consequently to count directly the 

 number of $ particles expelled from radio-active substances. 



Further work is in progress on this and other problems 

 that have arisen out of these investigations. 



Edinburgh. 



Royal Society, July 13 —Prof. Crum Brown, vice-presi- 

 dent, in the chair.— .\n improved method of esterification : 

 G. E. Gibson. — .Nitric anhydride as a nitrating agent: 

 G. E. Gibson. — The significance of maximum electrolytic 

 conductivity : Prof. John Gibson. — The variation of 

 Young's modulus under an electric current, part ii. : Henry 

 Walker. In these experiments it was shown that the 

 curious changes in the value of Young's modulus when the 

 iron, steel, copper, or platinum wire was heated by an 

 electric current were not observed when the wire was 

 stretched under a load approaching the limits of elasticity, 

 and that when the wire w^as heated by ordinary methods 

 no peculiarity in the change of Young's modulus was found 

 to exist. — The theory of general determinants in the 

 historical order of development up to 1S60 : Dr. Thomas 

 Muir. 



July 20. — Dr. R. H. Traquair, vice-president, in the 

 chair. — A sensitive state induced in magnetic substances 

 and materials by thermal treatment, part ii. : J. G. Gray 

 and A. D. Ross. The sensitive state induced by anneal- 

 ing the material from moderately high temperatures was 

 reduced by jarring, but could not be completely obliterated 

 by this means. A strong sensitive state was induced when 

 the material was cooled from room temperature to that 

 of liquid air, or when it was heated from the temperature 

 of liquid air to that of the room ; but when the material 

 was cooled to the temperature of liquid air and then 

 heated again, only a small increase was observed in the 

 susceptibility. The effect was associated with temperature 

 change, and was not apparently influenced by the length 

 of time the material was kept at the high or low tempera- 

 ture. — The structure of Tiirrilepas peachi and its allies ; 

 F. R. Cowper Reed. An examination of type-specimens 

 from Whitehouse Bay and of further material shows that 

 the organism is bilaterally symmetrical. There are four 

 series of plates, a double median longitudinal row of small 

 triangular plates in close contact overlying the larger and 

 more elongated lateral kite-shaped plates. The latter_ are 

 arranged in pairs on each side, extending (in the middle 

 part of the body) nearly at right angles to the axial line, 

 but becoming inclined more acutely forwards towards the 

 anterior end. The lateral plates also overlap each other 

 for about half their width, and bear on their outer surface 

 a median longitudinal impressed narrow groove which 

 appears as a fold on the reverse side of the plates. The 

 characters of Tmrilepas scotica were discussed in the light 

 of the newly discovered structure of T. peachi, and of fresh 

 material from the Balclctchie beds, and the Scottish species 

 were compared with the undescribed forms from the 

 Ordovician beds of England and Wales, and with the 

 .American genera Strobilepis and Lepidocoleus. — The re- 

 calescence of nickel : T. A. Lindsay. Two cylinders, one 

 of nickel and one of copper, were allowed to cool simul- 

 taneouslv from a high temperature, the difference of 

 temperature at each instant of time being measured by a 

 thermoelectric couple with the two junctions in the heart 

 of their respective cylinders. The difference curve of cool- 

 ing so obtained indicated recalescence phenomena at 

 temperatures of 650" C, 515° C, and within the range 

 370° C. to 285° C. — Note on the study of polarisation by 

 means of the Dolezalek electrometer : A. F. Ewan. The 

 method afforded a very delicate test of the independence 

 of polarisation on the potential of the electrode, and it 

 was also found possible to extend the time curve of 

 polarisation through a much greater range than had been 

 possible with any one of the other methods. Interesting 

 corroboration was obtained of Bouty's and Wiedeburg's 



