Modern and Roman agriculture, when
compared, present this remarkable contrast, "The
Roman agricultural authors never look forward,
but backward." They do not hope to increase
crops, they only to prevent them from
falling off. The Englishman fully maintains,
and in half a century has largely increased, his
per acre produce.

In the modern farming of the highest order
on our light lands that order that raises the
greatest possible amount of corn and meat from
a given space—the land is constantly treated,
not as a mine of wealth, to be continually worked
by the spade or the plough, according to the
dream of poets, but as a mere sponge, with
which fertility is annually infiltered in the shape
of manures, in order to be extracted in the shape
of crops. As long as the average supply of food
in England was equal to the average demand,
farmers were content to farm by the rule of
thumb—that is, by making use of the experience
of their forefathers and their neighbours; but
when the demand exceeded the supply, when
they were invited to buy manures as well as
seeds, they were compelled to consult the
chemist, and learn the reason why of many
operations they had long blindly and often
successfully followed. At the same time, it must
be admitted that according to the experience of
most exact observers there must be some
material difference between the effect of
cultivation under a British and an Italian climate.
We have plenty of light sandy soils, like
important districts in Norfolk, Bedfordshire,
Cambridgeshire, and Lincolnshire, which, without
sheep, root culture, oil-cake, and artificial
manure, would rapidly revert to the condition of
the barren wastes from which they were
reclaimed by liberal landlords and enterprising
tenants, but we can find no instances in
which a fair loamy soil of average fertility,
cleverly cultivated, has ever been actually
exhausted.

Mr. T. B. Lawes, who has expended upwards
of twenty thousand pounds in agricultural
experiments on his estate of Rothamstead, which
have been carefully recorded in the Journal of
the Royal Agricultural Society, grew wheat for
twenty years on one acre of fair loamy soil; the
result was sixteen bushels the first year, seventeen
and a quarter bushels the last year, and an
average of sixteen and a quarter bushels during
the twenty years.

Thirty years ago—perhaps if we were to
write twenty-five we should be nearer the mark
—the farmer relied for keeping up the fertility
of his farm almost entirely on sheep feeding and
his farm-yard manure; he did not always take
great care of that. If he lived, say in the
midland counties, he heard, perhaps, that the
Cheshire dairymen were using bones, or if in the
west of England, man lime, but he had no means
of learning whether either would suit his
midland fields. It was the gradual increasing use
of artificial, or rather portable, manures, that
first introduced the farmer to the chemist. The
acquaintance, which seemed very unpromising at
first, has ripened into an intimate and mutually
profitable connexion. The use of rape cake,
bone-dust, and other than farm-yard or such
accidental manure as seaweed or sprats, grew up
by imperceptible degrees long before farmers
obtained any other guide than experience of the
special value of each kind of fertiliser. Thus in
the west of England, from immemorial times,
lime was used with great effect, especially in
reclaiming waste land, for lime has a double value,
first in assisting to burn up and decay exuberant
half-dead vegetable matter of peaty and other
soils, and next as supplying itself to soils where
lime—an important constituent—was absolutely
wanting.

We have no authentic record of how bones
first came to be tried as a manure. There is a
vague story that the first experiment was
accidentally made of an accumulation of horse-bones
near a kennel of Yorkshire fox-hounds.
At any rate, in the time of Arthur Young,
the Cheshire farmers found out that broken
and crushed bones had a great effect in restoring
the fertility of pastures exhausted by
centuries of feeding for dairy purposes. We know
now that bone-dust restores to pastures the
very constituents—phosphate of lime—that are
removed by milk, butter, and cheese; but the
practice was pursued long before the chemical
reason was discovered. From dairy pastures
crushed and ground bones found their way to
the turnip-fields, which were coming into use on
every good farm a hundred years ago. The
bones seemed to complete a circle of treatment
that came into use about the same time. Turnips
fed sheep, which, before root cultivation was
introduced, could only be fed in winter on hay, a
scarce, expensive food. The sheep's manure
fertilised the soil while feeding, and prepared it
for the corn crop in the following year. As this
style of sheep cultivation was carried out on the
heaths, wolds, and commons of Cambridge,
Suffolk, Norfolk, and Lincolnshire, where
farm-yard manure was not too plentiful, the bones
came in, well distributed by a rude drill, to swell
the turnips that were to feed the manure-distributing
sheep. Very soon the bone-land farmers
found the advantage, adding to the flesh and
improving the manure, by giving peas, corn, and
eventually oil-cake, to their flocks.

Sir Humphry Davy's ingenious speculations
were the foundation of a school of agricultural
chemistry, but to his suggestions only a select
few farmers paid any attention. Amongst them
was, however, Mr. Coke of Holkham, who sixty
years ago drilled in turnip-seed, and used large
quantities of purchased rape-cake as manure.
But he and his tenants, with the Duke of
Bedford, Lord Yarborough, Mr. Chaplin, and their
tenants, stood almost alone for the next twenty
years in this astounding extravagance and daring
innovation.

The importance of the portable manure trade,
and the profession of an agricultural chemist,
date from 1835, when a Liverpool merchant
imported a cargo of Peruvian guano, the most
concentrated and powerful of portable manures.