1864. | Agriculture. 101 
might call it, to an upward current—which has hindered the passage of 
the air over that inner surface, is broken up. 
Land drainage is the provision of a passage for the rain-water, along 
with which the fertilizing air has thus a downward current given it 
through the soil and subsoil, And tillage, especially tillage by steam- 
power, which does not cake a floor, as horse-power does, beneath the 
soil it stirs—has all that enlivening effect of the poker on a caked coal 
fire, which the parallel suggests. Extended drainage has a great deal 
to do with our increased produce. Mr. Bailey Denton estimates that 
nearly 2,000,000 acres have within the past fifteen years been under- 
drained, and the fertility of these acres has no doubt been largely 
increased. ' 
Deeper and better tillage has contributed to the same result. The 
extension of autumnal tillage is an undoubted fact; the enormously 
increased use of implements of the grubber class is another ; the general 
_ adoption of a better form of plough is a third; the more general adop- 
tion of the fertilizing practice of burning clay soils is a fourth. The 
success which has at length rewarded unconquerable perseverance in 
the attempt to use steam-power for tillage operations is a further great 
fact, which, if it cannot yet be quoted in explanation of agricultural 
progress, will unquestionably be looked back upon ten years hence as 
having contributed largely to the increased fertility which will then 
have to be recorded. 
2. In the second place our agricultural progress has been owing to 
the greater richness of home-made manures, and to the greater use made 
of imported fertilizers. The imports of guano since 1840 have amounted 
to 3} millions of tons; the imports of cubic nitre, which averaged 
10,000 to 14,000 tons per annum up to 1858, have since varied from 
25,000 to 40,000 tons per annum. The imports of bones since 1848 
have increased from 30,000 to 70,000 or 80,000 tons annually. All 
these are manuring substances. 75,000 to 80,000 tons of Suffolk and 
Cambridgeshire coprolites, and 15,000 to 20,000 tons of Sombrero 
phosphate, are also used in the superphosphate manufacture, which now 
probably exceeds in worth £1,000,000 per annum. To facts like this 
add the enormous extension in the use of oil cakes and richer foods in 
the meat manufacture, by which the richness of home-made manure is 
increased—the increased adoption of the practice of applying manure 
at once to the land, instead of rotting it in heaps, which is an economy, 
and so an addition to our resources worth naming—the increased prac- 
tice of feeding and collecting manure under shelter, which is another 
great economy—and the increased care to properly pulverise and even 
dissolve manures, so as to distribute them thoroughly through the soil, 
which is another first-class example of a most important improvement 
in farm practice. On the other hand there is the increased value of 
the town sewage—due to the improved drainage of our towns—which 
is still suffered to go to waste. On the whole, however, there cannot 
be a doubt that the increased fertility of the soil is due not only to 
improved drainage and tillage, but to the direct application of fertiliz- 
ing ingredients in a more liberal and economical manner. 
3. Leaving now the soil, there is the way in which its increased 
