62 
On Bats' Guano. 
The exhaustion of the Chincha Island guano deposits, the 
limited supply of ammonia-salts and nitrogenous refuse-matter, 
and the constantly increasing demand for high-class artificial 
manures, have greatly stimulated of late years the search for 
natural fertilisers in all parts of the globe ; and, in not a 
few instances, enterprising explorers have been rewarded with 
success. 
Amongst the more recent discoveries of new sources of 
fertilising matters, those of considerable accumulations of Bats' 
guano deserve to be noticed. The object of the present Paper 
is to give a brief account of the chemical composition and the 
manurial properties of a number of samples of Bats' guano, 
which have been recently examined by me, and which I received 
from different places, where more or less extensive deposits have 
been found. 
As far as I have been able to obtain information, Bats' guano 
is found in Arkansas and Texas, in the south of Spain, in 
Jamaica, on several islands belonging to the group of the 
Bahamas, and on several East Indian Islands. 
Bats' guano consists of the more or less decomposed dung of 
bats, and of their dead bodies, mixed with variable proportions 
of earthy matter. It A-aries in colour from light brown to dark 
brown, and generally smells but faintly of ammonia. Some of 
the samples examined by me were light, powdery, dry, and full 
of fragments of the wings of insects ; others I found heavy, earthy 
in appearance, and quite void of smell. 
This fertiliser is found in caves, inhabited by innumerable 
bats, attracted to the neighbourhood of the caves by swarms of 
insects which infest certain swampy districts in semi-tropical 
countries, and W'hich afford abundant food to the winged 
mammals. 
The most extensive accumulations of Bats' guano appear to 
have been found in numerous rocky caves in Texas and Ai-kansas. 
Some of the caves yield comparatively little guano, others many 
hundreds of tons ; and from 15,000 to 20,000 tons are reported 
to have been taken from a single cave in Texas. The number 
of bats frequenting the caves amounts to millions, and when they 
issue forth they darken the air as if a great volume of smoke were 
pouring out from the opening. 
Caves covering miles of ground, and inhabited by innumerable 
bats, are also found in Arkansas ; and there can be no doubt 
that the caves in Texas and Arkansas contain large stores of 
bats' dung of sufficiently good quality to be usefully employed 
for agricultural purposes. 
