May 24,1924 Factors Influencing Binding Power of Soil Colloids 
513 
SUMMARY 
1. A method is outlined for testing the binding power of soil colloids by deter¬ 
mining the breaking strength of briquettes molded from soils under definitely 
established conditions. 
2. It is shown that the factors influencing the breaking strength of a briquette 
are: 
(a) The amount of moisture present at the time of molding. 
(b) The treatment of the material before molding the briquette. 
(c) The pressure applied. 
0 d ) The manner of drying. 
3. Some of the factors found to affect the binding power of soil colloids are:: 
(a) The amount of colloid present. 
(b) The size and grading of the noncolloidal material. 
(c) The kind of colloid. 
( d ) The dispersion of the colloid. 
4. A general relation between the load per gram of soil L, and the amount of 
colloid in the soil in per cent C, has been deduced and given expression in the 
formula, L=A2 C 1 - 24 . 
LITERATURE CITED 
(1) Anderson, M. S., and others. 
1922. ABSORPTION BY COLLOIDAL AND NONCOLLOIDAL SOIL CONSTITUENTS. 
U. S. Dept. Agr. Bui. 1122, 20 p. 
(2) Arnd, T. 
1923. EIN NEUES verfahren zur vergleichenden bestimmung der 
koharenz mineralischen boden. Ztschr. Pfianzenernahrung 
u. Diingung (A) 2: 130-149. 
(3) Atterberg, A. 
1912. DIE KONSISTENZ UND DIE BINDIGKEIT DER BODEN. Internal . 
Mitt. Bodenkunde 2: 149-189, illus. 
(4) Gile, P. L., and others. 
1924. ESTIMATION OF COLLOIDAL MATERIAL IN SOILS BY ADSORPTION. 
U. S. Dept. Agr. Bui. 1193, 41 p. 
(5) Jackson, F. H., Jr. 
1916. METHODS FOR THE DETERMINATION OF THE PHYSICAL PROPERTIES 
of road-building rock. U. S. Dept. Agr. Bui. 347, 27 p., illus. 
(6) Marquis, C. 
1915. VERGLEICHENDE UNTERSUCHUNGEN UBER DIE METHODEN DER 
koharenzbestimmung. Internat. Mitt. Bodenkunde 5: 381- 
516, illus. 
(7) Moore, C. J., Fry, W. H., and Middleton, H. E. 
1921. METHODS FOR DETERMINING THE AMOUNT OF COLLOIDAL MATERIAL 
in soils. Jour. Indus, and Engin. Chem. 13: 527-530, illus. 
(8) Puchner, H. 
1913. VERGLEICHENDE UNTERSUCHUNGEN UBER DIE KOHARESZENZ 
verschiedener bodenarten. Internat. Mitt. Bodenkunde 3: 
141-239, illus. 
(9) Robinson, W. O. 
1922. the absorption of water by soil colloids. Jour. Phys. 
Chem. 26: 647-653. 
