WATER SOILS. 1039 



observed in a humus soil containing nitrogen, 1.32 per cent; phosphoric 

 acid, trace; lime, 0.42 per cent; and potash, O.Oof! per cent. 



The results of the observations on the production of nitric nitrogen 

 were as follows : 



Nitric nitrogen produced in 1,000 grams of soil in 40 days. 



Mg. 



Check 2.8 



Potassium carbonate (0.1 per cent) 57. 8 



Peat ashes (0.5 per cent) . . .' 10. 2 



Unleached ashes (0.5 per cent) 19. 



Leached ashes (0.5 per cent) 3. 3 



Calcium carbonate (2 per cent) .- 5. 3 



Marly clay (2 per cent) 7. 5 



Burnt clay (2 per cent) 7. 



Potassium sulphate (0.1 per cent) and calcium carbonate (2 per 



cent) 32.5 



Potassium chlorid (0.1 per cent) and calcium carbonate (2 per 



cent) 38.0 



Potassium chlorid (0.1 per cent) and slag (5 per cent) 41.5 



The results of the observations on the formation of ammoniacal 

 nitrogen were as follows: 



Ammoniacal nitrogen produced in 1,000 grams of soil in .' I days. 



Mg. 



Check 4.0 



Potassium carbonate (1 per cent) 15. 



Potassium carbonate (0.5 per cent ) 40. 



Potassium carbonate (0.25 per cent) 02. 



Potassium carbonate (0.1 per cent) , 82. 



Sodium carbonate (1 per cent) 



Sodium carbonate (0.5 per cent) 46. 



Calcium carbonate (1 per cent) 4.7 



Potassium chlorid (0.5 per ceut) and slag ( 1 per cent) 130. 



Potassium chlorid (0.25 per cent ) and slag (0.5 per cent) 96. 



The best results were obtained with the mixture of muriate of potash 

 and slag, which has also been successfully applied in practice. The 

 alkaline carbonates in small amounts favored the production of both 

 ammoniacal and nitric nitrogen, but the action of both the ammonia 

 and nitric ferments was checked by the application of large amounts of 

 these carbonates. Calcium carbonate exerted little influence except 

 when used in connection with potassic fertilizers, the effect in this case 

 probably being due to the potassium carbonate formed by double decom- 

 position. The vigorous action of the potassium carbonate is attributed 

 to the power of forming potassium hamate, which readily undergoes 

 nitrification. This formation of humates appears to be an indispensa- 

 ble condition in improving the fertility of humus soils, and is probably 

 best secured by using a mixture of potash salts and calcium carbonate, 

 which, as stated above, yields potassium carbonate in the soil. If the 

 soil is already rich in potash, the desired result may be accomplished 



