39<5 
These results show that although these guanos are comparatively 
rich in phosphoric acid— of which a fairly large proportion is so- 
luble in ammonium citrate solution and is therefore in a form in 
which it could be utilised by plants — they are deficient in the very 
important constituents, potash and nitrogen. The guano of com- 
merce obtained in Chili and Peru contains as a rule from 7 to 12 
per cent, of “total nitrogen , ” r 1 to 14 per cent, of phosphoric acid, 
3 to 6 per cent, of potash, and 1 1 to 15 per cent, of lime (present 
as calcium phosphate). Comparing these figures with those ob- 
tained in the course of this examination of the bat guanos from the 
Federated Malay States, it will be seen that although the latter are 
fairly rich, particularly as regards samples A and 3, in phosphoric 
acid, yet this deficiency in the other important constituents of 
manures — viz., potash -and nitrogen — would prevent their being 
used as general manures in the same way as South American 
guanos, and they could only be satisfactorily employed in conjunc- 
tion with other materials rich in potash and nitrogen. They re- 
semble to some extent the so-called phosphate guanos, now 
imported in considerable quantities into this country, which, how- 
ever, contain as a rule at least 30 per cent, of phosphoric acid in 
the form of calcium phosphate. 
The best of the four bat guanos from the Federated Malay States 
is sample A, which contains 2 per cent, of potash,* 2.47 per cent, 
of nitrogen in the form of ammonium nitrate, and 17.52 per cent, 
of phosphoric acid in the form of ferric, aluminium and calcium 
phosphates. An unusual constituent of this sample is 28 per cent, 
of calcium sulphate. The phosphoric acid content of this guano 
would be worth about £2 i6j. per ton in this country, and it is 
unlikely that the small amounts of “ nitrogen ” and potash present 
would enhance its commercial value; This price is undoubtedly 
too k>w to permit of profitable export, and it would probably prove 
more remunerative to employ the guano locally. In this connection 
it may be mentioned that the calcium sulphate present in the 
material, though of no direct value as a manure, might be utilised 
indirectly by using the guano in conjunction with dung or any 
similar material which would undergo ammoniacal fermentation, as 
the ammonia and carbon dioxide generated by the fermentation 
would convert the calcium sulphate into arnmonium sulphate and 
calcium carbonate, thus affording at once two important constitu- 
ents of manures, viz., “ nitrogen ” and lime, in forms in which they 
can be readily assimilated by plants. Calcium sulphate is frequent- 
ly used in this way as an indirect manurial agent, and is regularly 
mined in the United Kingdom for this purpose. 
The other guanos, Nos. 1, 2 and 3, would be of comparatively 
little commercial value in this country, but there is no reason why 
they should not be utilised in the Federated Malay States as phos- 
phatic manures. When used in this way it must be understood 
that the soils to which they are applied may also require applications 
of other manures containing nitrogen and potash. It is noticeable 
that in samples Nos. 1, 2 and 3, taken at the surface, and six inches 
