SOILS. 121 



the soil were collected from the cock below. Tlu^se solutions were 

 submitted to analysis before and after this operation. 



The result shows that the mineral substances especially were rapidly 

 removed. Chlorin was promptly washed out. Suli)huric acid at hrst 

 appeared in the drainage water, but disappeared after 10 days. The 

 proportion of this substance increased after the addition of saline solu- 

 tions. The proportion of organic matter was considerable at first, but 

 gradually decreased. Organic and ammoniacal nitrogen were always 

 found in appreciable quantities. Nitric nitrogen was washed out by 

 pure water to a moderate extent, but when a solution of nitrate of soda 

 was added this salt appeared immediately in the drainage water. Only 

 a trace of phosx)horic acid was removed from the soil by jjure water, 

 but when superphosphate was added the proportion M^as considerably 

 increased. Potash was washed out promptly and the quantity was sen- 

 sibly increased by adding solutions containing superphosphate. 



The changes which certain chemical conqiounds undergo in the so 1 

 were also investigated. The method used was as follows: 100 gtii. 

 of the soil was shaken up with 500 cc. of a. solution containing a few 

 decigrams of the salt, allowed to stand 15 hours, and filtered, the solu- 

 tion being analyzed before and after this treatment. 



With the chlorids of potash, soda, and ammonia it was found that 

 the proportion of chlorin remained unchanged, but that the bases had 

 in every case been replaced by lime. Chlorid of calcium and sul- 

 phate of calcium were unchanged. With sulphate of potash, sulphate 

 of ammonia, and sulphate of iron the sulphuric acid was not retained, 

 but with the first two the bases were replaced by lime, and with the 

 third by lime and nitrogen. With sulphate of soda the sulphuric acid 

 was not fixed and the soda was not replaced by lime to any apiprecia- 

 ble extent. The results with jjhosphate of potash show, that a large 

 proportion of both potash and phosphoric acid was fixed in the soil and 

 that there was no appreciable replacement of potash by lime. The 

 results indicate, therefore, that phosjihate of potash may be used on 

 calcareous soils without danger of loss of its two fertilizing constituents 

 in the drainage water. A large proportion of the phosphoric acid of 

 phoi)hate of soda was fixed, and there was very little, if any, replace- 

 ment of soda by lime. When a solution of superj^hosphate was used 

 the phosphoric acid was largely fixed and the proportion of lime in the 

 filtrate was increased, probably on account of the sulphate of lime in 

 the superphosphate. From the solution of jjhosphate of ammonia a 

 large part of the phosphoric acid and about half of. the ammoniacal 

 nitrogen was fixed, and there was no substitution of lime for the latter. 

 With nitrate of potash the nitrogen was completely removed in the final 

 solution, but a considerable proportion of the potash was retained, its 

 place being taken by lime. Similar results with reference to the nitric 

 nitrogen were obtained with a solution of nitrate of soda, but the soda 

 was not replaced to any appreciable extent by other bases. Nitrate of 



