ACTION OF LIME AS A MANURE. 
19 
have a capacity for producing ammonia and prepare the nitro¬ 
genous substances for the subsequent nitrification. In those 
soils such as marshes, bogs, and peat, tbe chemical composi¬ 
tion of which prevents nitrification, the decomposition ends, 
according to this author, in the formation of ammonia. In 
course of time the ammonia may be again reconverted into 
organic compounds by the numerous fungi and algae which 
inhabit the soil in general. 
Many of the constituents of soils, organic as well as in¬ 
organic, have a strong chemimal affinity to the ammonia thus 
produced, and protect it usually very well from being washed 
away in the course of the irrigation. Lime, however, particu¬ 
larly if applied as oxide or hydrate, is likewise apt to be 
absorbed, and if incorporated with the soil, occupies some of 
the places in which otherwise the ammonia would find protec¬ 
tion, or dislodges it from the compounds into which it had 
already entered. Thus losses of nitrogenous substances take 
place and the field gradually becomes impoverished in this 
very essential vegetable nutrient in consequence of frequent 
liming, as we have already pointed out. 
In soils poor in lime but rich in ferric compounds the 
application of lime seems to favour the action of soluble 
phosphatic fertilizers on crops. In an experiment made last 
year to ascertain the manurial value of various kinds of 
phosphates for rice, we compared, amongst several others, 
sodium phosphate and double superphosphate, and were sur¬ 
prised to find that the latter had a far better effect than the 
former. As both these are soluble in water and are speedily 
absorbed when they are mixed with our soil, the difference 
in their effect must have been due to the combination into 
which they enter in the soil. Sodium phosphate is sure to 
yield there chiefly phosphates of iron and alumina while the 
double superphosphate which almost entirely consists of 
monocalcium phosphate will most probably be converted ni 
