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witli acetate of lead, decompose the deposit under watei' with 

 sulphuret of hydrogen; precipitate the liquid after filtering off 

 from the sulphide of lead (quinovin and a little quma-red), with 

 sub-acetate of lead ; dissolve the deposit, after filtering, in diluted 

 acetic acid (quina-red remaining undissolved), and precipitate the 

 acid filtrate with ammonia. Wash the light-yellow deposit, de- 

 compose by svilphuret of hydrogen, filter off from the sulphide of 

 lead, and precipitate the filtrate again with alcoholic solution of 

 acetate of lead. After the deposit, consisting of Quinotannate of 

 lead, has been decomposed under water with sidphuret of hydrogen, 

 and after the liqiiid, freed from the sulphide of lead by filtering, 

 has been evaporated in a vacuum over sulphuric acid and of a 

 mixture of sub-sulphate of ii"on and lime, the Quinotannic acid 

 remains, though already a little altered. — It is light-yellow, friable, 

 very electric and hygrosco])ic ; of an acidulous and very acerb, not 

 bitter taste ; dissolves readily in water, alcohol, and ether ; yields 

 on heating no pyrocatechuic acid ; is precipitable by glue, becomes 

 green with salts of oxyd of iron. 



QuillOVa-Red=:Ci2 H^ O5. In Quina-nova bark (from 

 Cinchona species). Precipitate the decoction of the bark with 

 acetate of lead, decompose the precipitate, consisting almost entirely 

 of the Red, under water by means of sulphuret of hydrogen,, 

 wash the resulting mixture of Quinova-red and sulphide of lead 

 with water, and boil with alcohol, and precipitate the Quinova-red 

 from the filtrate by means of much water. — Almost black, lustrous, 

 resinous substance, friable to a dark-red powder; dissolves 

 sparingly in water, readily in alcohol, ether, and alkalies ; is pre- 

 cipitable from the alcoholic solution by an alcoholic solution of 

 acetate of lead, not by tartarated antimony. 



Qlliliova-Tanilic Aci(l=:Cu Hg Os. In the bark Quina nova 

 or Surinamensis (from Oascarilla magnifolia). Precipitate the 

 decoction with acetate of lead, remove the deposit, containing 

 quinova-red, divide the filtered liquid into three parts, precipitate 

 one of them completely by sub-acetate of lead, and mix with the 

 remaining two ])arts. The deposit, which contains quinovin, the 

 rest of the quinova-red, and a little Quinova-tannic acid (but 

 which cannot be used with advantage for the preparation of the 

 latter) is also removed, and the liquid precipitated by sub-acetate 

 of lead. Decompose the washed precipitate under water by 

 sulphuret of hydrogen, remove the sulphide of lead, drive away 

 the sulphuret of hydrogen by heating, add acetate of lead, and 

 mix the filtrate with a great quantity of strong alcohol, whereby 

 flocks of Quinova-tannate of lead are obtained. From these isolate 

 the acid by sulphuret of hydrogen, and evaporate in a current of 

 carbonic acid gas. — Amber-yellow, translucid, friable substance, of 

 acerb and slightly bitter taste; dissolves in water and alcohol, not 



