on the Temperature of Soils. 
125 
lower strata; and it may, at the same time, remove fertilizing: 
matter. If drains are not deeper than the worked bed, water 
remains below in a stagnant state, which must chill the roots of 
plants, and diminish the temperature of the superincumbent mass. 
Gardeners and florists are well aware of the injurious influence 
of water when supplied constantly to the pan instead of to the 
surface of the soil in the flower-pot ; and bottom water, as it is 
frequently and very appropriately called, produces the same ill 
effects when stagnating too near the surface of the great agricul- 
tural bed. 
Superficial drainage is comparatively of little value, and is, per- 
haps, exemplified in its worst practical form by land tortured on 
the ridge and furrow system. When land is permanently culti- 
vated in hieh ridses. the crowns can obtain but partial benefit from 
the action of rain. The gradation from the comparative dryness 
and warmth of the summit, to the suffocating wetness and coldness 
of the furrows, is commonly evidenced by thd state of the crops 
grown on land so disposed.* 
Physical Properties of Earthy Matter. 
The influence of drainage and pulverization on the temperature 
of soils is, necessarily, dependent on the habits and constitu- 
tion of the solid as well as of the fluid matter composing or 
mixed with the soil. The variety of substances which enter 
into its composition ; their peculiar structure ; the state of their 
di\'ision or size of their particles ; their colour ; their respective 
pjwers of absorbing, conducting, and radiating heat ; their bibu- 
lousness ; all these properties conspire to the determination of 
the temperature of a given soil : and these properties are irre- 
spective of latitude or locality. Chemists have informed us of the 
specific heat, of the absorbing and radiating energy of various 
earths, and of many soluble and insoluble bodies, when submitted 
separately to investigation ; but we possess little or no knowledge 
of these relations, when such various substances are blended to- 
gether, as we find them to exist in the agricultural bed. It is there 
we should seek for information ; it is on the mass of the soil itself 
• It would be curious — but, possibly, more curious than useful— fo learn 
the origin of this remarkable artificial configuration given to land, which 
is, I fancy, peculiar to England and to particular counties. One would 
think that this system must have been invented previous to the discoveiy 
that water would find its way into cut drains : or, the inventor may have 
considered rain as his greatest enemy, and that he ought to prevent its 
entrance into the soil and get rid of it as soon as possible. I once put the 
question, as to the utility of this process, to a few farmers in Cheshire with 
whom I was in company. Their notion was that an undulating, being 
greater than a plane surface, more stuff would grow on it. It stood to 
reason that such must be the case ! This was debated at great length, I 
contending it was a fallacy. On a division I was left in a minority of one. 
