CARBONATE OF LIME. 127 
ers of great size and power were installed at lime- 
stone quarries and quantities of limestone dust ac- 
cumulated. Finally men began hesitatingly to use 
this limestone dust. The results were astonishingly 
good. Then quarrymen began advertising the 
ground limestone and selling it at a low price. The 
farmers took hold of it in Ohio, Illinois and some 
other states, and at last quarrymen began installing 
large crushers and grinders that took the raw rock 
from the quarry and reduced it to powder, making 
the whole output fit for farm use. This is usually 
put on cars in bulk and sold for from 75 cents to 
$1.50 per ton. The low price quoted is from a point 
in Illinois where the writer believes the state, with 
convict labor, grinds limestone for agricultural 
purposes. 
Limestone Harmless—This ground limestone is 
harmless to the soil, so one may use as much of it 
as he chooses. Dr. Cyril G. Hopkins of the Illinois 
experiment station has applied it at the rate of 100 
tons to the acre with not the least sign of injury to 
the soil. It is pleasant stuff to work with, not acrid 
and biting like burned lime if it gets on your skin, 
nor does it get caked together if it happens to get 
wet. One may put it on his soil at any time that 
suits his convenience. He may put it on in connec- 
tion with manure if he wishes and no harm will 
result. It cannot burn out the humus, it attacks 
nothing. Soil acids attack the particles of limestone 
and are neutralized, but the lime itself does no harm 
no matter how much is used. It is nature’s way of 
