nued year
after year. At the conclusion of the experiment the produce obtained
from each plot should be carefully weighed.

_Educational Value of Field Experiments._

The educative value of such experiments is very great, and in this
connection the remarks made by Mr F. J. Cooke, in a recent lecture
delivered to the London Farmers' Club, are worthy of most careful
consideration.

"Local experiments," he says, "teach the simple principles which should
determine the selection of manures, as well as scientific accuracy and
method in their use. The value of experiments is thus brought home to
men who would not go far to discover it; and the practice of a few
simple trials upon a correct system, each on his own farm, is
encouraged. That such trials may be conducted with very little expense
to the farmer, or other difficult qualifications, and yet to his great
practical advantage, I will venture to assert on the ground of my own
personal experience. For some twenty years I have annually conducted
private experiments on a very humble scale, and am not aware of any
other separate practice which has been so useful to me. It has been
pursued upon two light-land farms in different parts of the same county.
Yet, in respect of manurial requirements, the proper treatment for one
of them has differed so essentially from the other that a common
practice upon both would have been simply ruinous."

_Value of Manures deduced from Experiments._

Tables have been constructed for the purpose of showing the comparative
value of different kinds of manures as deduced from such experiments,
and may be fittingly compared with the tables giving the trade prices.
We have already quoted some of these tables in the Appendix to the
chapter on Mineral Phosphates. These tables show the relative intrinsic
value of different forms of phosphatic manures. In the Appendix[252] to
this chapter tables showing the relative value of different kinds of
nitrogenous and potash manures will be found.

_Value of Unexhausted Manures._

A subject which has had much attention devoted to it of late years is
the question of the value of unexhausted manures in the soil. In the
Agricultural Holdings Act special provision is made for giving
compensation to the out-going tenant of a farm for unexhausted manures
in the soil. The Act has given rise to endless disputes between landlord
and tenant, owing to the extreme difficulty of arriving at a
satisfactory estim