108 ELEMENTS OF AGRICULTURE 



tin can with soil. Pour on the water and compare the color of that 

 which is poured on with that 'which runs through. 



47. Examination of Bacteria. 



Materials. Compound microscope, magnifying about 500 to 1,000 

 diameters. 



Moisten some soil. Take a drop of the water and examine under 

 the microscope for bacteria and other organisms. 



COLLATERAL READING 



Soils, by S. W. Fletcher. 



Physics of Agriculture, by F. H. King. 



The Soil, by F. H. King. 



The Fertility of the Land, by I. P. Roberts. Pp. 34-130. 



Bacteriology in Relation to Country Life, by J. G. Lipman. 



Cyclopedia of American Agriculture, Vol. I, pp. 323-531. 



Dry Farming. Farmers' Bulletin No. 329, pp. 10-15, and No. 262, 

 pp. 15-18. 



Reclamation of Salt Marshes. Farmers' Bulletin No. 320, pp. 9-12. 



Management of Soil to Conserve Moisture. Farmers' Bulletin No. 

 266. 



