282 WiUSWG ACID, 



Experiments This being proved, the author varied his experiments, fo 



with pure alkali. ^^ j^, ^e thoroughly convinced of the fads. He alfo endea- 

 voured to afcertain, whether alkalies, freed from carbonic 

 acid, were better calculated for the produftion of pruffiated 

 alkali; and, if poffible, to find out the proper proportions of 

 ingredients for obtaining this fait. With that view, a quan- 

 tity of folution of potafh, containing one ounce of alkali freed 

 from carbonic acid, was mixt with three ounces of blood, 

 and evaporated to drynefs. (It was of a colophony colour, 

 foluble in water, and emitted, on being heated, a very ftrong 

 Low heat pro- odour of ammonia). On being transferred into a crucible, 

 Son 0"?."*' ^""^ gradually heated till no more flame appeared, and diffufed 

 acid and the aU through four ounces of water, it yielded a limpid fluid, of 

 ^^^* a ftrong alkaline tafte, and odour of bitter almonds. The 



ufual experiments proved, that it contained comparatively 

 little pruffiated alkali, but a large quantity of carbonate of 

 potafti. 

 Exp. to deter- Being thus convinced that this experiment proved fruitlefs, 

 mine the proper- j^ ^g^g deemed neceflary to afcertain the refpedtive quantity 

 ate and blood re- of oxide of iron contained in the prufliated alkali, that might 

 qiiifite to pro- jjg produced from a given quantity of blood and carbonate of 

 ^t^ Sec. potafli. 



The experi- With that view, four ounces of dried blood were mixt with 



ments witli low ^ folution of carbonate of potafli, containing one ounce of 

 4 oz*. blood and Carbonated alkali : the mixture, after being evaporated to 



1 alk. carb. drynefs, was heated till the flame ceafed to appear. It now 



weighed 1^ oz. On being elixiviated with eight ounces of 

 water, it afforded a fluid of a very pale yellowifti brown, or 

 wine colour : Its tafte was alkaline, mixt with that of bitter 

 almond' Two drachms of water mixt with 20 drops of a 

 concen):ated folution of muriate of iron, when decompofed 

 Produa very by this prufliated alkali, afi'orded four grains of prufliian blue, 

 liitle. ^f jpt^ f^Qjjj, the adhering oxide of iron by muriatic acid. 



2 oz. blood, Two ounces of dried blood and one of carbonate of potafli, 

 1 carb. alk. treated in a fimilar manner, yielded, by being mingled with 

 Pr'^dua'notin- » like quantity of muriate of iron, 4f grains of pure pruflTian 

 creafed. blue. 



(The Remainder in our next.) 



Obftrvations 



