244 S. W. Johnson on the Soil-analyses of the 
The above, we are of opinion, proceeded rather from the 
enerous heart than from the critical brain of its lamented author. 
ad he attempted to do the things which he believed to be so 
easy, we are sure his statements would have lost somewhat of 
their directness and would have appeared in a form highly modi- 
fied from the above. “The usual proportion of ingredients in an 
average soil.” What is an average svil? Our only way 
deciding what is such a soil consists in noting the average Y ield 
of soils. But the yield depends not alone on the soil, but upon 
climate, weather, tillage and various incidents and accidents. It 
tion of ingredients” alone, but likewise on the condition of 
those ingredients, their state of combination, their solubility. It 
h 
say how many thousandths of a per cent of potash, lime, phos- 
r. Peter has indeed attempted to show the degree of availa- 
bility of the elements of the soil by the following process. | A 
uantity, generally thirty grammes of the air-dried soil is 
placed in an eight-ounce strong vial, with a close fitting stoppe™ 
and the bottle is filled up with distilled water which has boot 
charged with pure carbonic acid gas, under a pressure of aboub 
two atmospheres. The bottle is allowed to remain for about® — 
