at any rate, we have no evidence of it.
The facts are all the other way. We have discussed this question at
considerable length in the pages of this book, and it is not necessary
to say more on the subject. I would, however, particularly urge farmers,
especially those who are using phosphates freely, to grow as much clover
as possible, and feed it out on the farm, or plow it under for manure.

The question is frequently asked, whether the use of phosphates will
ultimately impoverish our farms. It may, or it may not. It depends on
our general management. Theoretically, the use of a manure furnishing
only one element of plant food, if it increases the growth of crops
which are sold from the farm, must have a tendency to impoverish the
land of the other elements of plant food. In other words, the use of
superphosphate furnishing only, or principally, phosphoric acid, lime
and sulphuric acid, must have a tendency to impoverish the soil of
nitrogen and potash. Practically, however, it need do nothing of the
kind. If the land is well cultivated, and if our low, rich, alluvial
portions of the farm are drained, and if the hay, grass, clover, straw
and fodder crops are retained, the more phosphates we use, the richer
and more productive will the farm become. And I think it is a fact, that
the farmers who use the most phosphates, are the very men who take the
greatest pains to drain their land, cultivate it thoroughly, and make
the most manure. It follows, therefore, that the use of phosphates is a
national benefit.

Some of our railroad managers take this view of the subject. They
carry superphosphate at a low rate, knowing that its use will increase
the freight the other way. In other words, they bring a ton of
superphosphate from the seaboard, knowing that its use will give them
many tons of freight of produce, from the interior to the seaboard. It
is not an uncommon thing for two hundred pounds of superphosphate, to
give an increase of five tons of turnips per acre. Or, so to speak, the
railroad that brings one ton of superphosphate from the seaboard, might,
as the result of its use, have fifty tons of freight to carry back
again. This is perhaps an exceptionably favorable instance, but it
illustrates the principle. Years ago, before the abolition of tolls on
the English turnpike roads, carriages loaded with lime, and all other
substances intended for manure, were allowed to go free. And our
railroads will find it to their i