ON rmjssic ACID. 277 



X. 



Memoir on the Nature and the new Properties of the PrvJJic Acid. 

 % Cit. Curaudau, corrcfponding Member of La SocietS 

 libre dea Pharmaciens de Paris *, 



1 HE Pruflic colouring matter has been long known in che- tXncertaintie» 

 miftry, but we have yet no correct knowledge of its nature t0 ' t hTtheory"of 

 and different modifications ; chemifts are not even agreed as Pruflic acid, 

 to the formation of this lingular fubftance. Some admit that 

 oxigen forms a part of its compofition, and others aflert it to 

 be an acid without oxigen. Indeed this composition performs 

 the functions of an acid in many inftances ; but in certain others, 

 and particularly in its fimple ftate, it ceafes to exhibit the pro* 

 perties common to other acids. This diverfity of opinions on 

 a (ubftance which we can compofe and decompofe, reduce and 

 combine at pleafure, feems to contradict our chemical know- 

 ledge, and to carry us from that perfection towards which 

 perfett fcience ought continually to tend. 



In fact, if in the clafs of acids it were proved that there Whether an 

 were one without oxigen; might we not conclude that thtf tf frhm t oariwm 

 bafes might, as well as oxigen, contain the acidifying princi- 

 ple, and would it not follow that we have gratuitoufly afcribed 

 to vital air the property of generating acid ? 



It is of importance then, under ihefe circum fiances, to fix The prefent ra- 

 the opinions of the chemifts on this point, and to determine termine the 

 what may be the concurring caufes that give the pruflic co- caufes by which 

 louring matter the characieriftic properties of acids, or to fe- Ja"^-^"^-" 6 

 parate it from their clafs. This is the problem which I have fied, and the 

 undertaken to refolve. If I have not fulfilled the talk, I dare contr31 7' 

 at leaft flatter myfelf that my observations will prove ufeful to 

 the prog re Hi of fcience, and that they may deferve the atten- 

 tion of the chemical world. 



In order to avoid the continual repetition of Pruflic acid, Adjustment of 

 Pruffic colouring matter, &c. I (hall in future defcribe this terras# 

 acid under the name of " Prujjire," its combinations without 

 oxigen " PrvJJiurets," and its oxigenated combinations " Pruf- 

 fiates." This correction of Nomenclature becomes- neceflary 



* From Les Annalcs de Chimie, No. 137. Vol. XL VI. p. 148- 



not 



