326 



The Guano left 

 from the firft 

 wafliing, 

 —contains uric 

 acid. 



Phofphate of 

 limC) iron, and 

 carbonate of 



—and left 

 ^artzofe and 

 ferruginous 

 fandi 



Recapitulation 

 of component 

 parts. 



Remarks. 



ON THE GUANO, 



Guano; and that themother-water certainly contains oxalates 

 phofphates, fulphates, and muriates of potafli, and of am- 

 monia. 



The five grammes and feven-lenlhs, left after the wadilng 

 of the ten grammes originally taken for analyfis, were treated 

 with cauftic polafh, which took up eight-tenths. This alka-. 

 line folution contained only uric acid, and a fmall portion of 

 fat matter. 



The 4.9 grammes left by the cauftic potafli, were treated 

 with muriatic acid : the producl was phofphate of lime, iron, 

 and an atom of carbonate of lime. 



After thefe applications of water, of cauftic potafli, and of 

 muriatic acid, there remained of the 10 grammes of Guano, 

 only 3.1 grammes of matter, compofed of quartzofe and fer- 

 ruginous fands. 



From the foregoing interefting analyfis, it appears that the 

 manure of the iflels of the South Sea is formed of, — 



1. Uric acid to the amount of | of the whole compound; 

 partly faturated with ammonia and lime : 



2. Oxalic acid, partly faturated v/ith ammonia and potafli : 



3. Phofphoric acid, combined with the fame bafes and with 

 lime : 



4. Small quantities of fulphate and muriates of polafh and 

 ammonia: 



5. A fmall portion of fat matter: 



6. Sand, partly quartzofe and partly ferruginous. 



The exiftence of Guano in places frequented by vaft num- 

 bers of bird;;, and the identity of its nature with that of the 

 excrements of aquatic birds, nec^fliarily throw confiderable 

 light on the origin of this matter. 



The analyfis proves how well founded was the ingenious 

 eomparifon of the learned naturalift, to whom we are indebted 

 for our knowledge of this fubftance, no lefs interefting to us 

 than ufel'ul to the inhabitants of Peru. It confirms (he im- 

 portant difcovery made by the refearches of Mefl^rs. Fourcroy 

 and Vauquelin. In a word, this analyfis pofl^effes the advan- 

 tage of proving a well-known maxim, that the fciences mu- 

 tually enrich and enlighten each other with the light they pof- 

 fefs; and it affords a new occalion to remark that among the 

 fciences, there are perhaps none which have fo immediate 

 and fo neceflary a connexion as Chemiftry and Natural 



Hiftory. 



XI. No^ 



