May, '14] 



GRANITIC SOIL POTASSIUM. 



15 



soils in other ways. In order to show these reactions, five 

 fairly representative soils were selected. Their analyses follow: 



Table VII 



Sample No. 1 is a light sandy soil, No. 2, a light clay loam, 

 No. 3, a sandy loam, No. 4, a heavy clay loam, and No. 5, a heavy 

 boulder clay. 



In order to show how fertilizers behave when they come in 

 contact with soils, solutions of various salts, of known strengths, 

 were percolated through columns of soils, the rate of percolation 

 being controlled by means of capillary tubes and the height of 

 the water level in the containing vessel. The flow was adjusted 

 at the rate of about 90 cc. per 24 hours. The strength of the 

 solutions was made uniform on the basis of the potassium equiva- 

 lent. The changes effected in the passage through the soil were 

 determined by studying the percolate. In this way, it was pos- 

 sible to determine what had been taken from and what had 

 been added to the original solution. 



All the chloride, nitrate and sulfate radicals were left in solu- 

 tion; for that reason these radicals were not considered further. 



