be caught for the purpose of conversion into manure. The difficulty of
preserving fish, however, is considerable; and he suggests the use of
potash salts, such as muriate of potash, or lime for this purpose. The
benefit of using potash would be twofold. In addition to acting as a
preservative, it would considerably enhance the value of the resulting
guano as a manure. There is much truth in Professor Storer's views; and
no doubt, as our sources of artificial nitrogenous manures grow more
limited, the manufacture of fish-guano will be carried on in the future
on a larger and more systematic scale than hitherto.

_Meat-meal Guano._

What is called "meat-meal guano" is generally that made from the refuse
of the carcasses of cattle after they have been treated for their
meat-extract according to Liebig's process. The meat-meal is used both
for feeding and manurial purposes. Considerable quantities[199] of this
guano are imported annually into this country from South America,
Queensland, and New Zealand,--that coming from Frey Bentos, in Uruguay,
being best known. It is a valuable manure, especially so for its
nitrogen, which varies from 4 to 8 per cent, while it contains of
phosphoric acid from 13 to 20 per cent. Some meat-meal guanos contain as
much nitrogen as 11 per cent.

In some parts of the world, more especially in Germany, the carcasses of
horses, as well as cattle, dogs, pigs, &c., which have died of disease,
are converted into a guano. They are subjected to treatment by steam in
digestors, by which means the fat and gelatine are separated and
utilised, while the remaining portion of the animal is converted into
guano. Other processes are also employed. The resulting manure contains
from 6 to 10 per cent of nitrogen, and from 6 to 14 per cent of
phosphoric acid.

_Value of Meat-meal Guano._

Meat-meal guano is a valuable nitrogenous manure. The same remarks
apply to it as to fish-guano, although it ferments probably very much
more quickly than the latter, and is undoubtedly a more valuable manure.

_Bat Guano._

In conclusion, we may consider bat guano. Bat guano, which is really a
very rare curiosity, has been found accumulated in hot climates in
caves.

The samples which have been analysed have differed very much in quality,
some containing as much as 9 per cent of nitrogen and 25 per cent of
phosphoric acid. Provided it could be obtained in any quantity, and of a
quality even approximating to the