Percy stared at these figures when he brought them together for
comparison. He then checked up his computations to be sure they were
right.

"Almost twenty times as much phosphorus!" he said to himself. "Is it
possible? And more than forty times as much calcium! Let me see! It
takes one hundred and seventeen pounds of calcium for four tons of
clover hay. The total amount in the plowed soil of the Leonardtown
loam would not be sufficient for eight such crops; and six crops of
corn such as we raised one year on our sixteen acres would take more
phosphorus from the land than is now left in the plowed soil of this
Leonardtown loam. The magnesium is not quite so bad--about one-fifth
as much as in our black soil, and the potassium is almost one-half
as much as we have."

Percy next turned to the Porters black loam, which he had noticed
was to be found not many miles from Montplain. He thought he might
induce Mr. West to drive with him to the upper mountain slope in
order that they might see that land. His computations for the
Porters black loam gave the following results:

4,630 pounds of phosphorus

48,300 pounds of potassium

12,360 pounds of magnesium

23,700 pounds of calcium

He viewed these figures a moment with evident satisfaction.