considerable amounts. As an average one-fourth of the phosphorus
contained in the food consumed is retained in the animal products,
especially in bone, flesh, and milk."

"Well, I didn't know that milk contained phosphorus," said Mr. West,
"although I did know, of course, that phosphorus must be contained
in bone."

"But, as you know," said Percy, "milk is the only food of young
animals, and they must secure their bone food from the milk.
Furthermore, the complete analysis of milk shows that it contains
very considerable quantities. There are also records of digestion
experiments in which less than one-half of the phosphorus in the
food consumed was recovered in the total manural excrements. As a
matter of fact there is a time in the life of the young mother, as
with the two-year old cow, for example, when she must abstract from
the food she consumes sufficient phosphorus for the nourishment of
three growing animals,--her own immature body, a suckling calf, and
another calf as yet unborn.

"Of course the organic matter of the soil should increase under
pasturing, especially under conditions that make possible an
accumulation of nitrogen; but here too the animals make no
contribution toward any such accumulation. With the same growth of
plants the accumulation of organic matter would be much more rapid
without live stock."

"It is known absolutely but not generally that live stock destroy
about two-thirds of the organic matter contained in the food they
consume. With grains the proportion is higher, and with coarse