708 AGRICULTURAL COLLEGES IN ENGLAND. 
take them seriatim , as I have casually set them down ; and 
to begin with geology, or the doctrine of the earth, and an 
acquaintance with its stratical structure. This surely cannot 
be considered a useless study to the farmer, whose whole 
business relates to, and whose whole profit is derived from, 
the earth. To know the nature of the soils of a farm, both 
above and beneath — to be acquainted with their names, 
properties, and compositions, is, in connection with chemistry, 
to become acquainted with the most beneficial mode of using 
or treating them. I shall give one instance in proof of the 
utility of such knowledge. 
In the great limestone plain of Ireland, extending over 
some of the most fertile portions of that fertile country, the 
produce of wheat had fallen off since the famine (1846), from 
twenty barrels (400 stones) per acre to from four to eight 
barrels. Various causes were assigned for this enormous 
deficiency. It was ascribed to the loss of the potato, the 
wearing out of the soil, &c., and even to more occult and 
moral causes, which it is needless to repeat. Upon a chemical 
analysis, however, of the surface soil at different points of 
this plain, by Sir Robert Kane, Professor Davy, and other 
scientific men, it was found that notwithstanding the abun- 
dance of limestone in the sub-strata, not a particle of lime 
could be detected in the upper soil ; consequently, the dis- 
continuance of the use of lime, which took place after the 
famine, deprived the land of those substances without which 
wheat cannot be profitably cultivated. 
A knowledge of mechanics embraces that of the prin- 
ciples on which all the operations of a farm are conducted ; 
and I have no hesitation in saying that, if such knowledge 
were generally diffused amongst the agriculturists, one third 
of the labour of the farm might be saved in many districts 
of this country, and a much larger produce obtained. This 
branch of science is closely allied with the two following — 
namely, pneumatics, or the doctrine of the air; and hy- 
draulics, or the science of the conveyance of water — this 
latter so essential in the irrigation of land, as well as in 
draining it. What do we not owe to the machinists of the 
present day for the vast improvements derived from the 
mechanical science they have brought to bear upon the sub- 
ject of the construction of machinery of every description 
used in husbandry ? What fortunes and what mental efforts 
have been spent in the process between the first conception 
of an instrument — say the reaping machine, for instance — 
and its arrival at perfection ! And yet, when the incipient 
idea is started, the projector is either too often ridiculed as 
