Thus, while 100 parts of the ash of wheat contain an
average of 45 parts of phosphoric acid, 100 of the ash of the wheat
straw contain an average of only 5 parts. The difference is as 9 to
1. In magnesia the disparity is only a little less striking.

In what are called the organic elements of wheat (the combustible
part) there are seven times more nitrogen in 100 pounds than in a
like weight of straw. Hence, if the farmer converts straw into
manure or compost, with the view ultimately of transforming it into
wheat, it will take 7 pounds of straw to yield nitrogen enough to
form one pound of wheat. Few are aware how much labor and money is
annually lost by the feeding of plants on food not strictly adapted
to the peculiar wants of nature in organizing the same. It is true,
that most farmers depend on the natural fertility of the soil to
nourish their crops, with perhaps the aid of a little stable and
barn-yard manure, given to a part of them. As the natural resources
of the land begin to fail, the supply must be drawn from other
quarters than an exhausted field, or its cultivator will receive a
poor return for the labor bestowed.

In Great Britain, where the necessity for liberal harvests and
artificial fertilizing is far greater than in this country, the
yield of wheat is said to be governed in a good degree by the amount
of ammonia available as food for growing plants. This opinion is
founded not at all on theory, but altogether on the teachings of
experience. But in England, limeing and manuring are so much matters
of constant practice, that few soils are so improverished as many
are in the United States, With land as naked and sterile as is much
that can be found in the whole thirteen colonies between Maine and
Alabama, English farmers could hardly pay their tithes and poor
rates, to say nothing of other taxes, rent, and the coat of
producing their annual crops.

The first step towards making farming permanently profitable in all
the older States, is to accumulate in a cheap and skilful manner the
raw material for good harvests in the soil.

Over a territory so extensive as the United States, it is extremely
difficult to lay down any rule that will be applicable even to a
moiety of the republic. There are, however, many beds of marl,
greensand, gypsum, limestone, saline a