52 Alfred J. Lhrart : 



of a solvent gas. This may be the case here, although the 

 fluctuations in the percentage of acid -soluble and water-soluble 

 matter show no apparent relationship. The latter represents, 

 however, merely the condition at the time of taking, whereas 

 the former results from cumulative action prior to sampling. 



iMa.\- 18 Sept. 25 Dec. 30 



Plot 6 — Ammonium sulphate Surface 0.55(6.12) 5.64'(5.24) 6.16(5.82) 



(80lb. per acre) 8 inches 6.34(5.81) 5.7 (5.21) 5.7 (5.34) 



16 inches 6.25(5.7) 6.32(5.91) 4.8 (4.56) 



Averag-e 6.38(5.88) 5..S9(5.4o) 5.55(5.24) 



Here the acid- soluble matter undergoes on the average a dis- 

 tinctly greater reduction than in the previous plot, in spite of 

 it-^ lesser yield of crop. The variations closely follow those in 

 plot II., so that it appears as though acid-soluble matter 

 passes downwairds to some extent after prolonged rain, and 

 is slowly drawn upwards during prolonged drought. 



May IS Sept. 25 Dec. 30 



Plot 8— Star Phosphate Surface 5.36 (4.77) 5.06 (4.69) 4.36 (4.0) 



(4cwt. per acre) 8 inches 4.98 (4.64) 4.76 (4.23) 4.8 (4.36) 



16 inches 5.40 (4.92) 5.18 (4.76) 4.72 (4.28) 



Average 5.25 (4.78) 5.0 (4.56) 4.63 (4.21) 



May 18 Sept. 25 Deo. 30 



Plot 5— Bone Dust Surface 5.3 (4.79) 5.2 (4.68) 5.7 (4.26) 



(4cwt. per acre) 8 inches 4.92(4.35) 4.86(4.43) 4.58(3.87) 



16 inches 4.96(4.33) 4.82(1.3) 4.04(3.66) 



Average 5.06 (4.36) 4.96 (4.47) 4.67 (3.93) 



In plots III. and V. the ajmounts of manure added represent 

 0.56 gram per kilogram of the surface 2 inches, and 0.07 per 18 

 inches depth. Since only a portion of -each is soluble in the 

 the dilute acid used, it is evident that the steady fall represents 

 mainly materials previously present in the soil. In the i-tar 

 phosphate plot no superficial accumulation of acid-soluble materials 

 takes place in December, but this phenomenon is shown with 

 the bone dui^t plot, possibly because of secondaiy reactions 

 excited by the organic material of the bone dust. 



May IS Sept. 25 Dec. 30 



Plot 8.— Calcium Superphosph. Surface 6.08(5.24) 5.61(5.25) 4.1(3.62) 

 (2cwt. per acre) 8 inches 7.96(7.39) 7 2 (6.69) 4.4(4.0) 



16 inches 5.86(4.66) 5.22(4.5) 4.2(3.74) 

 Average 6.63(5.76) 6.01(5.58) 4.2(3.79) 



