gjg ANALYSIS OF SCAMMONY. 



Difference in Aleppo scammony is light, of an ashen gray, shining, 

 anc'e ^^^'^^^' transparent in its fracture. That of Smyrna is very com- 

 pact, heav}', of a darker colour, and more difficult to pow- 

 der. 



Aleppo scam- Examination of Aleppo scammony. 



exposed to H hen this scammony is pure, it melts entirely on a 



^^^^' heated plate of iron, and emits fumes of a nauseating smell. 



Treated with Triturated with water it renders it milky. With boiling 



'"'•iis'* water it concretes into a lump : the water becomes yellow, 



and has a bitter taste; but it is neither alkaline, nor acid ; 



which proves, that this substance is not adulterated with 



ashes, as some authors affirm. 



Alcohol at 40° [sp, grav. 0*817] produces a slight preci- 

 pitate in this aqueous solution ; and the acetate of lead 

 occasions a yellow flocculent precipitate soluble in nitric 

 acid. 

 and witb aico- The alcoholic tincture of scammony has a brownish yel- 

 ^"^^- low colour. It reddens tincture of litmus; and leaves 014 



evaporation a yellowish white and transparent resin. 

 Resin, This resin dissolves entirely in nitric acid, which it colours 



yellow. The addition of water renders this solution slightly 

 turbid. 

 Combines with It is equally soluble in a solution of pure potash, even 

 potash, without heat, when its colqur is yellow ; but, it heat be 



employed, it is brown. Water, even in pretty large quan- 

 and then with tity, does not precipitate any of the resin. If the solution 

 muriatic ^cid. be saturated with muriatic acid, the resin does not separate. 

 This triple compound of resin, acid, and potash, claims 

 the notice of practitioners : perhaps we may thus discover 

 a solvent for resins, that water would not render turbid. 

 Inioluhle part. The part of the scammony that was not soluble in alco- 

 hol assumed a gray colour when dry. Treated with boiling 

 water it coloured it yellow, and alcohol occasioned a wh^te 

 flocculent precipitate in it. 

 Experiments ^^'** determine the proportion of the constituent princi-r 

 to determine pies of Aleppo scammony, we took 100 part? -of tliis sub? 

 f>f itscompo- stance, and exhausted them by alcohol. The solution W^s 

 nent parts. yellow. A gray substance remained, which, whfn dried,, 

 yeighed 26, 



The 



