nd sulphate of ammonia. Of the former, the annual
exportation from Chili is close on one million tons, of which quantity
about 120,000 tons is imported into the United Kingdom. Of sulphate of
ammonia, on the other hand, the total production in this country is
about 130,000 tons per annum,[94] the greater proportion of which is
exported, leaving only from 30,000 to 40,000 tons for consumption.
Nitrate of soda, it must be remembered, is not entirely used for
manurial purposes, a small proportion of the above imports being used
for chemical manufacturing purposes.

_Peruvian Guano._

Peruvian guano is another important nitrogenous manure very much less
abundant now than formerly, as the different guano-beds have become
nearly exhausted. While the imports of this important manure into the
United Kingdom amounted in 1870 to nearly 250,000 tons, at present not
more than 11,000 tons are being imported.

_Bones._

A further source of nitrogen is bones, which, of course, are chiefly
valuable as a phosphatic manure, but which contain also some 3 to 4 per
cent of nitrogen. Of this valuable manure we import at present about
30,000 tons, while about 60,000 tons are collected in this country,
bringing up our total consumption to 100,000 tons.

_Other Nitrogenous Manures._

The above mentioned are the most important of nitrogenous manures; there
are, however, a number of other nitrogenous manures used in this country
in very much smaller quantities. As most of these substances are made in
this country, it is very difficult to estimate the amount of their
annual production with exactness. These substances are as follows:
fish-guano, meat-meal guano, dried blood, shoddy, scutch, horns and
hoofs, hair, bristles, feathers, leather-scrap, &c. Of fish-guano, the
total consumption per annum may be put down at about 8000 tons, of which
a fourth is imported into this country, the remaining 6000 tons being
manufactured at home. Of meat-meal guano, dried blood, hoof-guano, &c.,
about 2500 tons are annually imported, the home production bringing up
the total amount to some 10,000 tons. Of shoddy, some 12,000 tons are
manufactured in this country; while scutch--the name given to a manure
manufactured from the waste products incidental to the manufacture of
glue and the dressing of skins--is produced only to the extent of a few
thousand tons annually.

It is a fact worthy of notice, that while the use of phosphatic manures
has increa