with reference to the adoption of methods of soil improvement."

"Is the report of the analysis as confusing with respect to other
elements as with potassium and phosphorus, which, I understand, are
likely to be reported in terms of potash and a 'phosphoric acid'
that is not true phosphoric acid?"

"Still worse," Percy replied. "The calcium is commonly reported in
terms of lime, or, as you would say, quick lime; and vet the soil
may be an acid soil, like yours, and contain no lime whatever,
neither as quick lime nor limestone. I have seen an analysis
reporting half a per cent. of calcium oxid, which would make five
tons of quick lime in the plowed soil of an acre; whereas the soil
not only contained no lime whatever, but was so acid that it needed
five tons of ground limestone per acre to correct the acidity.

"The trouble is that when the chemist found calcium in the soil
existing in the form of acid silicate, or calcium hydrogen silicate,
he reported calcium oxid, or lime, in his analytical statement,
assuming apparently that the farmer would understand that the
analytical statement did not mean what it said."

"But some soils do contain lime, do they not?"

"Some soils contain limestone," replied Percy, "and the analysis of
such a soil should report the amount of limestone, or calcium
carbonate, based upon the actual determination of carbonate carbon
or carbon dioxid, which is a true measure of the basic property of
the soil, even though the limestone may be somewhat magnesian in
character."