November 14, 191 2] 



NATURE 



quently impossible to say whether the substance 

 formed is the desired compound or its mirror image. 

 The mechanism of such interactions has been fully 

 studied by E. Fischer in Berlin and A. McKenzie in 

 London, and it was appropriate that the latter should 

 give a concise though clear and logical summary of 

 the question, which is generally spoken of as the 

 Walden rearrangement, before the section. A con- 

 siderable discussion ensued. 



Dr. Lowry followed with a paper dealing with a 

 closely allied subject, that of isomeric change, and 

 more especially with those taking place in solutions 

 of the crystalline amide and piperidide of camphor- 

 carboxylic acid. This case is of exceptional com- 

 plexity, since the experimental measurements show- 

 that three distinct isomeric changes take place, and 

 that a condition of equilibrium is established ulti- 

 mately between four distinct isomerides. The equa- 

 tions for consecutive unimolecular changes of this 

 type were described at length, as well as the curves 

 representing change, and they were afterwards dis- 

 cussed by Prof. Soddy and others. 



The second part of Dr. Lowry's communication 

 dealt with the use of certain models to explain Barlow 

 and Pope's theory of molecular structure based on 

 valencv conceptions. A very fluent account was given 

 of a difficult subject, which was closely followed by 

 those present. 



The next two papers, by Prof. K. J. P. Orton, of 

 Bangor, and Prof. Holleman transferred attention 

 to the laws of substitution in the benzene series. 

 Prof. Holleman 's status in this field is well known, 

 and the section was fortunate in having his coopera- 

 tion throughout the meeting. Prof. Orton dealt with 

 the conversion of chloro-, bromo-, and nitro-amino- 

 benzenes into the carbon substituted anilines and 

 anilides, giving a detailed account of his recent work. 

 Prof. Holleman described w-ork carried out in con- 

 junction with Mr. J. P. Wibaut on the nitration of 

 the chlorotoluenes. He indicated the number of iso- 

 merides formed in the various cases, and showed 

 both how to calculate approximately their proportions^ 

 and how well these figures agreed with those deter- 

 mined experimentally by the laborious separation of 

 the constituents of the mixture. 



A brief communication by Dr. J. K. Wood, who 

 acted as local secretary for the section, was of con- 

 siderable interest. Leucine and similar amphoteric 

 substances are in reality internal salts, the acidic 

 and basic groups neutralising each other. When an 

 acid or base is added, the internal salt is broken up 

 and a true salt formed with the added acid or base. 

 In the case of an optically active substance it should 

 be possible to determine the rotation when the whole 

 of the internal salt has just been broken up, and so 

 calculate the acidic and basic constants of the ampho- 

 teric substance. Leucine is tevorotatorv in aqueous 

 solution, but on the addition of hydrochloric acid the 

 solution becomes increasingly dextrorotatory. When 

 about i'34 equivalents of acid have been added, the 

 effect of further addition is much smaller, and there 

 is a sharp bend of the curve at this point correspond- 

 ing with the complete disappearance of the internal 

 salt. 



Equally sharo results could not be obtained with 

 sodium hydroxide, owing to racemisation being caused 

 by the alkali. 



The method can be used at all events qualitatively 

 to measure the strength of the added acids ; the 

 weaker the acid the more concentrated it must be to 

 break up the internal salt. By working with a 

 common acid, various amphoteric substances may be 

 compared. 



Owing to the shortness of time. Prof. C. R. 



NO. 2246, VOL. go] 



Marshall gave a very brief account of the two papers 

 standing in his name. The action of bromine on 

 strychnine has been investigated with the object of 

 preparing a dibromo compound as described by some 

 authors, but this does not appear to exist. The 

 second paper dealt with pentaerythritol tetranitrate. 



The final communication on phototropy was de- 

 livered by the president, who showed specimens of 

 phototropic compounds obtained in the course of in- 

 vestigations on salicylidene amines. Of a large 

 number of such compounds examined, fourteen have 

 been found to exhibit phototropy distinctly — that is, 

 they change in colour on exposure to light. In 

 studying the influence of temperature on the pheno- 

 menon, it has been found that while some are photo- 

 tropic at temperatures up to their melting points, 

 others have a limiting temperature, above which they 

 are not phototropic, whilst in two cases compounds 

 which are not phototropic at the ordinary temperature 

 show this property below zero centigrade. 



The explanation of phototropy is still outstanding; 

 it has been considered in turn as due to intra- 

 molecular rearrangement, stereoisomerism and poly- 

 morphism. Another problem is the nature of the 

 energy evolved when the darker-coloured phototrope 

 in the' absence of solar energy, or possibly also when 

 under solar influence, returns to _ the lighter form : 

 this remains for future investigation. 



.A novel and successful feature of the meeting on 

 its less severe side was the sectional supper held on 

 the Saturday. E. F. A. 



J, 



THE DIFFUSION OF EDUCATION AND 

 KNOWLEDGE.^ 



HE educational status of a nation consists in the 

 amount of literacy, number of teachers, and 

 number of persons in its primary and secondary 

 schools, and in its colleges and universities, relative 

 to population. The status of knowledge may be indi- 

 cated by the number of books, periodicals, and news- 

 papers relative to population. This knowledge may 

 take two forms, one gained through books, the other 

 through periodicals and newspapers. One is know- 

 ledge in general ; the other consists more in current 

 information. 



The question may be asked, if a community or 

 country leads another in literacy, diffusion of educa- 

 tion and knowledge; if, relative to its population, it 

 has more pupils in school, more teachers, more 

 students in colleges and universities, more books in 

 its libraries to read, and more periodicals and news- 

 papers to peruse, is not this country or community, as 

 a whole, very probably better educated and more 

 intelligent than the other country or community? 

 While there are exceptions due to special conditions, 

 we are disposed to answer this question in the affirma- 

 tive. 



Table I. indicates in a general way the diffusion 

 of education and knowledge in some leading countries. 



Column I gives the relative amount of illiteracy 

 among army and navy recruits. As these are mostly 

 adults, they probably represent best the real amount 

 of illiteracy. Column 6 gives the number of publica- 

 tions (relative to population) in the list of the Smith- 

 sonian Institution in Washington. These publications 

 are of the highest class, including journals issued by 

 learned societies and governmental institutions. 



Examining Table I., it will be seen that Switzer- 

 land is much in advance of all the other countries in 

 general diffusion of education and knowledge, and 



1 From a paper on " MenlaV.iy of Nations in Connection with Patho- 

 Socia! Conditiors," by .\ithur Macdonald. in T/u- Oftn foio/ for August. 



