33^ Journal of Agricidturc. [8 June, 1907. 



once the necessary interactions between it and the soil constituents have 

 taken place its fertilising properties are almost equivalent to those of 

 Chili saltpetre ; the relative values ma\ be numerically expressed as 94 

 to 100. It is clear then that we have in this black powder a store of 

 valuable nitrogen, and though it requires more careful and judicious 

 handling than the other materials of this class, its manurial properties 

 are such as to warrant favorable consideration in the future. 



As Hall has remarked, " the chief practical drawback to the use of 

 cyanamide lies in the fact that it cannot be mixed with manures like 

 superphosphate, but must be sown separately and scuffled into the soil some 

 days before the seed is sown." The cause of this injurious action, if 

 sown along with or within a day or two of the seed, is believed by Wagner 

 to be due to the presence of excess of free ammonia or to a small amount 

 of the dicyanamide which is distinctly unfavorable to plant life. To 

 avoid this the lime nitrogen should be applied at least a week before 

 sowing. On argillaceous and peaty soils, in fact in all those deficient 

 in lime salts, this calcareous compound should yield excellent results. 



Peat and Nitrification. — An attempt has been made by Messrs. 

 Muntz and Laine to solve the nitrogen problem without invoking the aid 

 of electricity^ — always an expensive power to employ. In their earlier 

 experiments they obtained nitrates by saturating bone-black with a weak 

 ammoniacal solution, and allowing time for the nitrifying organisms to 

 perform their function. Subsequently they hit upon the notion of sub- 

 stituting peat for animal black as being of a more open porous nature, 

 and therefore more favorable to rapid bacterial action. In this process 

 the peat is broken up, mixed with lime, infected with bacteria and soaked 

 with a weak solution of ammonium sulphate, and it is found that the 

 drainage water contains nitrates which can be obtained bv evaporating 

 the liquor. At first the drainage water is not rich in nitrates, but if the 

 ■' filtration " be repeated several times — weak ammonia solution being 

 added to the drainage water each time — up to 22 per cent, of nitrates 

 may be obtained. However, the nitrification of ammonia in this wav has 

 very little bearing upon the expansion of the field of origin of the world's 

 nitrates for the same process is operating at a slower rate in practically 

 all our soils, and there is moreover no reason to expect that the artificial 

 nitrification of ammoniated solutions can ever be turned to profitable 

 account. 



The feasibility of their latest suggestion, namely, the utilisation of the 

 peat nitrogen which amounts to about 2 per cent., instead of weak solu- 

 tions of sulphate of ammonia, deserves further consideration. By means 

 of the wet process of distillation, in which a current of superheated steam 

 is employed, from 80-90 per cent, of the constituent nitrogen has been 

 extracted from peat, so that we may fairly hope in the near future to 

 hear of still further advances along this line of investigation. 



