SOILS. 705 



Tlie solvent action of concentrated mineral acids, hydrochloric^, nitric, 

 and sul[>luiric, was tested on the same sample of soil and compared 

 with the results obtained by the fusion method. 



"Coiiceutrated hydrochloric acid, 40 per ceut strength, dissolved 2^ per cent more 

 of the complex silicates than nitric acid of tlie same strength. Concentrated nitric 

 acid possesses a stronger solvent action than the dilnte hydrochloric acid. The con- 

 centrated hydrochloric acid dissolved somewhat more potash than the hydrochloric 

 acid of 1.115 sp. gr. The amonnt of lime, phosphates, and sulphates dissolved by 

 the concentrated hydrochloric acid was about the same as when the more dilute 

 acid was used; the concentrated acid, however, dissolved more of the complex sili- 

 cates of potash, iron, and alumina. Suljihuric acid jiossesses the strongest solvent 

 action. 



"Of the total i>otash in the soil as determincid by fusion, k'ss tliau 18 per cent is 

 soluble in the hydrochloric acid as nsed in soil analysis; about 10 per cent is soluble 

 in oxalic acid, and 3 per cent in tartaric acid." 



The chemical analysis of the soil in its relation to fertilizer 

 experiments, von Liebenberg and E. von Proskowetz, Jr. {Blitt. 

 Ver. Ford, landw. Versuchw. Oesterr., 1894, No. 9.,pt. 1, pi). 23-35). — As 

 in the two x^revious years (E. S. E., 5, \). 702), the soil of plats contain- 

 ing 100 square meters on which fertilizer experiments on barley and 

 oats were made was carefully sampled and analyzed and the results of 

 analysis compared with the action of the fertilizers emj)loyed. In pre- 

 vious analyses only the phosi)horic acid and nitrogen were determined, 

 while in the present case potash soluble in nitric acid was also esti- 

 mated. The results in general confirm those of iDrevious investigations. 

 Nitrogen was found to be as a rule more abundant in the soil than in 

 tlie subsoil. The relation of phosphoric acid in the soil and subsoil was 

 variable, being influenced evidently by the previous system of culture 

 and manuring. The same was tiiie in general of the potash. In the 

 heavy soils used the potash was in almost every case considerably 

 higher than the phosphoric acid and frequently higher than the lime. 

 The soils are therefore much benefited by calcareous manures. 



The experiments with barley indicated that in unfertilized soil the 

 yield varied directly with the amount of nitrogen present. As in pre- 

 vious years, the yield was greater the greater the i)roportion of nitrogen 

 to phosphoric acid, provided a sufficient amount of phosphoric acid 

 and potash was present. The ratio of phosphoric acid to nitrogen in 

 the first series of soils was 1 to 1.38, in tlie second series 1 to 1.00. In 

 almost every case the soils responded to applications of nitrate of 

 soda, although the soils contained amounts of nitrogen varying from 

 17 to 84 kg. per 100 square meters of soil. 



With phosphatic fertilizers the results were irregular, but as a rule 

 they were effective on barley on soils containing an average of 24.5 kg. 

 of phosphoric acid in 100 square meters of the surfiice soil, and on oats 

 on soils containing an average of 23.4 kg. It is concluded that on soils 

 containing more than about 40 kg. of phosphoric acid per 100 square 

 meters of surface soil manuring with phosphates is of doubtful value or 

 14467— No. 8 3 



