SOILS, MANURES, &c. 241 
Dungs muft never be buried too deep 
in the earth, beyond the aftion of the 
air, becaufe in fuch a fituation they will 
■ ’ \ 
ftagnate, corrupt, and become putrid, 
and poifonous to plants. 
In order to difcovet* whether a foil 
contains any metallic or mineral acid 
falts, the following experiment is re¬ 
commended, viz. Take a few pounds 
weight of the foil, at about twelve or 
fifteen inches below the furface, becaufe 
that of the furface ought not to be 
confidered a fair fpecimen, being fubjefl 
to the influence of the atmofphere, and 
walhing of rains; put it into an earthen 
veffel, and pour as much boiling hot rain, 
or diflilled water, upon it, as will com¬ 
pletely cover it; Itir it well together, 
that the falts may be perfeflly diffolved, 
and let it Hand till the earth fubfides; 
filtre off a little of the water, through 
I i filtrating 
