324 O^ THE GUANO, 



The liquor, filtered and again evaporated, till reduced (d 

 3 grammes, on cooling again, depofited a fawn'-coloured 

 powder, fimiiar to the former, but in lefs quantity. 



The powder, and the mother- water,, which had held it in 

 folulion, were feparately examined, 

 Ixaminaticn of ^^^ powder offered the following properties : — It is a con- 

 tbepowder, Crete and pulverulent fubUance, of a brilliant cryftalline af- 

 pe6i, and of a dull yellow colour. Before the blow-pipe it is 

 coalumed entirely away, yielding a flight empyreumatic odour 

 o^ ammonia and pruflic acid. It is very little foluble in 

 cold water; but abundantly fo in warm water, to which it 

 communicates its yellowifh colour. This folution, though 

 lafJelefs, ftrongly reddens the tincture of turnfole, precipitates 

 Solutions of acetate of lead, and of nitrate of filver and mer- 

 cury, in coloured flakes, which are readily and completely 

 rediflblved by nitric acid. 



This matter inftantaneoudy diflToIves in an alkaline ley, 

 which it tinges of a deep brown colour, exhaling a pungent 

 Cmell of ammonia. Sulphuric acid poured into the concen- 

 trated alkaline folution, throws down a very thick whitilh pre- 

 cipitate, and difengages a briflc odour, refembling that of 

 weak acetic acid. 

 it Is an acidu- ^^^ learned authors of this memoir conclude from their ex- 

 lous fair, com- periments, that this powder is an acidulous falf, compofed of 



pafcd of animai animal acid, ammonia, and a little lirne. In fad, very weak 



acw, ammonia, ' ' , . ■' 



and lime. nitric acid, wherein this fait had been macerated in order to 



difengage the acid it contained, from its bafes, yielded, on 



evaporation, copious ammoniacal vapours, by the addition 



of potafli, and unequivocal figns of the prefence of lime, by 



the addition of oxalic acid. 



AnaTyfis of the When thus deprived of its ammonia and lime, this matter 



powder when j^ ]q[^ coloured and Itfs foluble than before. Its folution in 



ammonia and boiling water depofits pretty hard and brilliant cryfials, and 



time, more deeply reddens turnfole paper. It combines readily, 



and without any ammoniacal vapour, with pofafli, from which 



all the acids again leparate it. Heat turns it black ; and it 



burns, without leaving any refiduum, with an odour of am- 



ir.onia and of pruflic acid. A neutral combinatiou of it with 



ammonia will not: precipitate the folution of fulpbate of alu- 



mine, as is done by iiouiltic acid. 



From 



