reater than it can ever be in England, and when we
suffer from severer droughts than are common there, we may not find
substantial practical advantage from the passage of these air currents
through the soil.

We are not aware of experiments in America, accurate enough to be quoted
as authority on the subject.

CHAPTER XIV.

DRAINAGE ADAPTS THE SOIL TO GERMINATION AND VEGETATION.

Process of Germination.--Two Classes of Pores in Soils, illustrated
by Cuts.--Too much Water excludes Air, reduces Temperature.--How
much Air the Soil Contains.--Drainage Improves the Quality of
Crops.--Drainage prevents Drought.--Drained Soils hold most
Water.--Allow Roots to go Deep.--Various Facts.

No apology will be necessary for the long extract which we are about to
give, to any person who will read it with attention. It is from a
lecture on Agricultural Science, by Dr. Madden, and we confess ourselves
incompetent to condense or improve the language of the learned author.

We think we are safe in saying that it has never been before published
in America:

"The first thing which occurs after the sowing of the seed is, of
course, _germination_; and before we examine how this process may
be influenced by the condition of the soil, we must necessarily
obtain some correct idea of the process itself. The most careful
examination has proved that the process of germination consists
essentially of various chemical changes, which require for their
development the presence of air, moisture, and a certain degree of
warmth. Now it is obviously unnecessary for our present purpose
that we should have the least idea of the nature of these
processes: all we require to do, is to ascertain the conditions
under which they take place; having detected these, we know at once
what is required to make a seed grow. These, we have seen, are air,
moisture, and a certain degree of warmth; and it consequently
results, that wherever a seed is placed in these circumstances,
germination will take place. Viewing matters in this light, it
appears that soil does not act _chemically_ in the process of
germination; that its sole action is confined to its being the
vehicle, by means of which a supply of air and moisture and warmth
can be continually kept up. With this simple statement in view, we
are quite prepared to consider the variou