June 6, 191 8] 



NATURE 



279 



Hoard of Education as eligible for grant during 

 016-17 was 931, and in them there were 198,759 

 upils, of whom 103,819 were boys, as compared with 

 .89,487 pupils, of whom 99,205 were boys in the same 

 number of schools during 1915-16. In addition to 

 'he 931 schools on the grant list, the Board recog- 

 lised 125 other schools as efficient, and in these 

 M hools, during 1914-15, 25,033 pupils were being 

 ducated. Though the numbers for 1916-17 are not 

 available, the report says it is probable that the 

 number of pupils in these efficient schools increased, 

 on the whole, in about the same proportion as in the 

 schools on the grant list. The Board of Education 

 has found that the withdrawal from the schools of the 

 younger and more vigorous masters, and their replace- 

 ment by others of lower physique, of more advanced 

 years, and often of inferior qualification, is an educa- 

 tional loss for which there can be no effective com- 

 pensation. The effect of increased entry and enforced 

 stoppage of building has been to cause serious over- 

 crowding, which, unfortunately, must for the present 

 be regarded as inevitable. 



I\ his presidential address to the Society of British 

 ( ias Industries, Sir Robert Hadfield devoted one sec- 

 tion to a consideration of the world's facilities for 

 higher education. According to his investigations, there 

 are about 280 universities in the world, with some 

 ^MO '"special colleges" and 100 technical schools, 

 faffed by about 53,000 trained teachers and investi- 

 ..;ators. Excluding India, the white population of the 

 British Empire is about 65 millions, served by 

 48 universities, which gives one university for each 

 \\ millions of population. In Great Britain and 

 Ireland, with a population of some 45 millions, there 

 are 18 universities, which works out at one university 

 for each 2^ millions of population. In Canada, Aus- 

 tralasia, and South Africa, where the population is 

 distributed over very much larger areas, the propor- 

 tion is naturally higher, and is about one university 

 for each two-thirds of a million population. In France 

 and Italy the proportion is just about the same as 

 in Great Britain and .Ireland. As regards Germanv, 

 if the technical high schools of university rank are 

 grouped with the universities, the proportion is one 

 per two millions of the inhabitants. In Austria- 

 Hungary the proportion is about one per 45 millions, 

 and in Russia it is only one per 14 millions of popula- 

 tion. The country which contains the largest number 

 of universities, both absolutely and in proportion to 

 population, is the United States of America, where one 

 university exists for each million of inhabitants. Sir 

 Robert Hadfield gives an interesting table showing the 

 < hief subjects dealt with in universities and technical 

 -chools, and the number of universities at which each 

 ubject is taught. 



j in terms of primary red, green, and violet is given 



! diagrammatically by means of Maxwell's chromatic 



I triangle for nine examples. It is noticed that the 



I sequence of colours in some of these agrees closely 



' with those of tempered steel. It is shown that the 



I colours of tempered steel are not " colours of thin 



' plates," and it is suggested that they must be due 



' to the formation of some material the molecular period 



I of which is comparable with the period of light-waves. 



and not to a structure comparable with the wave- 



I length. — J. C. M. Garnett : General factors in mental 



measurements. An inquiry into the mathematical 



argument for the existence of Prof. Spearman's 



\ general factor g, in all mental abilities of which 



'• measurements had been published during many years, 



led to an investigation into the consequences that 



must follow from the condition that the correlation 



between every pair of columns in a correlation table 



is ±1. These consequences were found to be that 



there is one, and only one, factor common to all 



the qualities the correlations of which form the table; 



that there are no group factors common to two or 



more qualities but not to all ; and that there may be 



any number of specific factors each belonging to one 



quality only. It was found that any quality which is 



I distributed according to the normal law, and depends 



only on n independent factors (qualities), say 



x^x. . . . x„, which are distributed according to the 



normal law and have the same standard deviation, 



may be represented by 



where 





+ Lx„ 



. L 



SOCIETIES AND ACADEMIES. 



Lo.NDON. 



Royal Society, May 16. -Sir J. J. Thomson, presi- 

 dent, in the chair. — .\. Mallock : Note on certain 

 coloured interference bands and the colours of tem- 

 pt^red steel. After alluding to the interference bands 

 -I en when two rows of posts, etc., or two gratings, 



ire viewed one through the other, the paper deals 

 with a particular case of such bands, namely, that 

 when a plate of dispersive material, such as glass, is 

 placed between the two gratings, or, which amounts 

 '.) the same thing, when a single grating is placed on 



I thick mirror, and the interference takes place between 

 ;lie grating and its reflective image. The bands so 

 formed are coloured. The composition of the colours 



NO. 2536, VOL. lOl] 



The standard deviation of q, moreover, will be the 

 same as of XtX.^ . . . a„. The existence is indicated 

 of a third general factor c ("cleverness") independent 

 both of Prof. Spearman's g ("general ability") and 

 of Dr. Webb's w ("purpose"). How much would be 

 known concerning the mental qualities of an indi- 

 vidual whose g, u>, and c had been measured is dis- 

 cussed in concluding the paper. — C. M. Williams : 

 The absorption of X-rays in copper and aluminium. 

 The paper deals with the relation between the mass- 

 absorption coefficients of X-rays in copper and 

 aluminium and the respective wave-lengths over a 

 range of 043 1-0637 .\.U. The relation between the 

 two absorption coefficients are examined and the 

 dependence of each of the latter on the wave-length. 

 .\ notable feature is the occurrence of discontinuities 

 in the curves representing the results ; these may 

 probablv be connected with the J-series recently 

 described by Barkla. With respect to the appro.ximate 

 relation between the mass absorption coefficient /x//j 

 and the wave-length X given by the equation 

 /x//3 = aA»» + C, where a, n. and C are constants, it 

 appears that, while the relation is fairly well satisfied 

 in the case of copper by giving n the value 5/2— a 

 result in conformity with Owen's 5th-power absorption 

 law — the results for aluminium show a value n = 3. — 

 Dr. T. R. Merton : The electrical resolution and 

 broadening of helium lines, (i) The broadening of 

 helium lines bv condensed spark discharges is in dose 

 1 agreement with the electrical resolution of the lines. 

 ! (2) The "isolated components" in the electrical resolu- 

 j tion which have been recorded by Brunetti, and by 

 Takamine and Yoshida, have been found in the 

 broadened lines. (3) An explanation is offered of the 

 relative degree of broadening of liijes of the " arc " 

 ! and "spark" tvpe, on the supposition that the latter 

 ' act as a kind of safety valve to the former when the 

 intensity of excitation becomes very great. (4) It is 

 i suggested that the "isolated components" are not a 



