110 kaye. PRINCIPLES OF SOIL MECHANICS [Ch. 5 



trie and thermal impulses has led to a number of attempts in recent 

 years to drain and stabilize soils by electrical methods. Although 

 it is widely believed that this is essentially a phenomenon of the elec- 

 tric double layer, or the charged layer of oriented water molecules on 

 granular surfaces previously mentioned in connection with plasticity, 

 there is still need for additional investigation into the cause of electro- 

 and thermo-osmosis before large-scale application becomes practicable. 

 The list of questions on fundamental soil properties is long, and the 

 solution of any of them would undoubtedly be of value to both soil me- 

 chanics and geology. In the field of applied soil mechanics there is 

 no reason to advocate that geologists should, or even could, replace 

 engineers in the purely engineering application of soil mechanics. The 

 geologist's role will probably continue to be that of a consultant on 

 engineering matters, and the final decision regarding design will un- 

 doubtedly always remain the engineer's responsibility. Greater aware- 

 ness, however, of geologists of the utility of soil mechanics would re- 

 sult in the training of more geologists able to answer in a quantitative 

 way not only the engineer's quantitative questions on soils, but also 

 some of geology's quantitative questions on earth materials. 



REFERENCES 



American Society for Testing Materials (1939). Symposium on shear testing 

 of soils. 



(1944). Procedures for testing soil. 



American Society of Civil Engineers (1940). Selected bibliography on soil me- 

 chanics: Manual of engineering practise, No. 18. 



Boston Society of Civil Engineers (1940). Contributions to soil mechanics, 1925- 

 1940. 



Burmister, D. M. (1938). A study of the physical characteristics of soils, with 

 special reference to earth structures: Columbia Univ. Dept. Civ. Eng., Bull. 6. 



Campbell, F. B. (1939). Graphical representation of the mechanical analyses of 

 soils: Trails. Amer. Soc. Civ. Engrs., June 1939. 



Casagrande, A. (1936). The determination of the preconsolidation load and its 

 practical significance: Proceedings First International Conference on Soil Me- 

 chanics, vol. 3, p. 60. 



(1947). Classification and identification of soils: Proc. Amer. Soc. Civ. 



Engrs., pp. 783-810, June 1947. 



, and Carrillo, N. (1944). Shear failure of anisotropic materials: Jour. 



Boston Soc. Civ. Engrs., April 1944. 

 , and Fadum, R. E. (1940). Notes on soil testing for engineering purposes: 



Harvard Univ. Grad. School of Eng., Soil Mechanics Series, No. 8. 

 Coulomb, C. A. (1776). Essai sur une application des regies de maximis et minimis 

 a, quelque problemes de statique, relatifs a, l'architecture : Memoires par divers 

 savans etrangers, Academie des Sciences, Paris. 



