June i6, 1921] 



NATURE 



505 



v.ith the seasonal variations of the salts in the soil 

 solution and with the absorption of nutrient elements 

 by the plant, and the latter with the mechanism of 

 osmotic phenomena associated with the root-hairs of 

 the plant. 



In the discussion of this group of papers Dr. 

 Hackett dealt with the capillar}- rise of water in 

 soils, and Mr. Wilsdon mentioned some interesting 

 exf>eriments on hygroscopicity and osmotic pressure. 



The second group of papers, on the organic con- 

 stituents in the soil, opened with a review by Mr. 

 H. J. Page (Rothamsted) of the nature and properties 

 of the organic matter and its influence on soil mois- 

 ture, soil temperature, and the reaction, composition, 

 and concentration of the soil solution. Prof. Oden 

 gave an account of his important researches on 

 humus from peat soils, in which he has shown that 

 the term " humic acid" is chemically correct. Dr. 

 E. J. Salisbury (University College, London) described 

 experiments on the relations between organic matter 

 and the vertical distribution of acidity in natural soils. 



In the discussion Dr. Ormandy directed attention 

 to the necessarily complex nature of the material used 

 in Prof. Oden's experiments, and suggested that 

 parallel experiments on a simpler substance like china- 

 clay would be useful. 



In the third section — adsorption phenomena — Mr. 

 E. M. Crowther (Rothamsted) dealt with the measure- 

 ment of the hydrogen-ion-concentration of acid soils, 

 both electrometrically and with the indicators used by 

 Clark and Lubs. Mr. E. A. Fisher (Leeds University) 

 critically discussed the application of the adsorption 

 formula to soil problems, in view of the empirical 

 nature of the equation and the facility with which, by 

 numerical modifications, it can be used to fit experi- 

 mental data of phenomena which cannot be related. 

 He showed that the modified form of Way's chemical 

 theory, vvhich assumes exchange of bases by double 



decomposition between silicates and added salts, 

 would account for the observed phenomena. 



Dr. Russell in the course of the discussion referred 

 to the necessity for taking account of the colloidal 

 rnaterial known to exist in soil and the consequent 

 difficulty of accepting an exclusively chemical explana- 

 tion of base exchange. 



A paper in this section by Mr. C. T. G. Morison 

 (School of Rural Economy, Oxford) on pan formation 

 was taken as read, as was also Dr. Mellor's introduc- 

 tory paper in the concluding section — colloidal pheno- 

 mena — on the plasticitv of clays from the ceramic 

 point of view. Prof. Od^n gave an account of his 

 work on clays as disperse systems. He described the 

 apparatus employed, which" consists essentially of a 

 balanced plate on which the suspended particles' slowly 

 settle, the gradual increase in weight being auto- 

 matically recorded. Mathematical analysis of the data 

 enables a distribution curve to be constructed, giving 

 the percentage of particles present between anv 

 specified range of diameters. 



Mr. N. M. Comber (Leeds University) dealt with 

 his suggestive experiments on the flocculation of soils, 

 in which the difference between silt and clav was 

 shown, and the conclusion drawn that clay is pro- 

 tected by an emulsoid of a siliceous nature. 



In the concluding paper Mr. G. W. Robinson (Uni- 

 versity College, Bangor) indicated certain physical 

 constants of soil which would be of great help when 

 employed statistically in soil surveys. 



The forthcoming publication of the papers and dis- 

 cussion by the Faraday Society will be of use not onlv 

 to soil investigators in general, but also to members of 

 bodies such as the Association of Economic Biologists 

 and the Agricultural Education Association, which, 

 among others, were invited by the Faraday Socletv to 

 co-operate in the discussion. 



B. A. K. 



British Science Guild. 



NoTi\BLE Views on Present-day Problems. 



Aiy ELL-KNOWN leaders of scientific thought dis- 

 •* cussed the difficult and pressing problems of 

 the times with hopefulness, sagacity, and insight at 

 the fifteenth annual meeting of the British Science 

 Guild, held at the Goldsmiths' Hall on Wednes- 

 day, June 8. The president (Lord Montagu of 

 Beaulieu) was in the chair, and there was a large 

 and representative assembly, which welcomed with 

 much gratification the announcement that his lordship 

 had consented to occupy the presidency for another 

 year. 



The president, in opening, expressed their sincere 

 sense of loss at the death of Sir Norman Lockyer, 

 who not only took a great interest in the work of 

 the Guild, but was also one of its most distinguished 

 founders. They had also sustained another serious 

 loss in the death of Sir William Mather. During 

 the past year the Guild had given consideration to 

 many matters of importance to scientific workers. 

 They held that civil servants in these days ought, at 

 any rate, to be of scientific mind or appreciate science, 

 even though they might not be highly educated in 

 science itself. The work of the State year by year 

 needed more and more scientific handling and treat- 

 ment, and the Civil Service as a whole should be 

 encouraged to consult scientific men and to have re- 

 course to scientific advice when occasion demanded. 

 They had tried to spread their influence from London 

 to the provinces, and so far had been very successful. 

 They were doing their best to bring in great pro- 

 vincial centres, which in many ways were more 

 promising scenes for scientific education than London 

 NO. 2694, VOL. 107] 



itself. He was sorry they could not announce that 

 day what they hoped last year would be the case — a 

 conference with the representatives of Labour. They 

 thought they had better wait for a calmer state of 

 things before they asked either Capital or Labour or 

 representatives of the State to consider their mutual 

 relations to each other and to science. He thought 

 they ought to ask themselves in regard to the generally 

 unsettled state of the country, in fact of nearly all 

 civilised countries to-day, whether it was possible to 

 go on putting up our scale of living for all classes 

 and to reduce our hours of work at the same time ; 

 and, what was more serious in many cases, reduce 

 the output more than in proportion to the number of 

 hours put in. It was quite certain that in this 

 country, if we were to compete with the world and 

 maintain a high standard of living at the same time, 

 we must increase our output per man of machine 

 work even if we worked shorter hours. That was a 

 very difficult problem to solve, but he did not despair 

 with the help of science, in some trades at any rate, 

 of its solution. Then they had to aim at the 

 better education of all classes in scientific facts 

 and inculcate more and more the scientific habit of 

 mind. But our system of education must be less of 

 the parochial and insular kind and more scientific, 

 broad, and world-wide in outlook. The difficulty to~ 

 day, he thought they would agree, was that in many 

 of the great subjects which they had to consider facts 

 were very difficult to get at. Science aimed at the 

 truth, and in social and political matters, as well as 

 in scientific matters, if they knew the real facts, a 



