M. Rochleder on Frazetine. 49 
with water and decomposed by sulphuretted hydrogen, and the 
liquid filtered from the sulphide of lead formed. This filtrate 
yielded, on careful evaporation, a substance crystallizing in fine 
silky needles, which possessed a feebly acid reaction, and in 
appearance and properties greatly resembled gallic acid. This 
substance Hlasiwetz has named quercetic acid. Its most cha- 
racteristic property is its relation to oxygen. When a drop of 
alkali is added to a very dilute solution of the acid, it imme- 
diately turns yellow, and when agitated in the air gradually 
becomes of a brilliant red. The formula of the acid was found 
to be C% H!? 016, 
From its general resemblance in appearance and properties it 
appears to stand closest to ellagic acid, with which it is homo- 
logous. 
C#H?O'% | . Quercetic acid 
C#8H® Ol€ , . Ellagic acid 
C® Hé 
If this be the formula of quercetic acid, that of quercetine 
must he altered. Hlasiwetz considers that it has the formula 
C*° H'°Q*, and expresses its decomposition by the following 
equation :— 
C45 HS 0% 4 2HO=C!? H6 0S + C34 HOM, 
Quercetine. Phloroglucine. Quercetic acid. 
Hence the original formula for quercitrine must be altered. 
Quercitrine contains the elements of sugar, of phloroglucine, and 
of quercetic acid. 
9(Cl2 HzO! 
COE Of =1\'C? HE, O85 — 6HO. 
Quercitrine. C34 FI}? O16 } 
This formula would require that quercitrine should yield in its 
decomposition 46:3 per cent. sugar. Rigaud found 44-9 per 
cent. Other experiments, however, by Hlasiwetz and by Roch- 
leder, with specimens of various preparation, yielded quantitics 
of sugar which correspond to 1 and to 8 equivalents of sugar. 
It seems therefore probable that different kinds of quercitrine 
may exist containing different proportions of sugar, analogous 
consequently to the natural oils and fats with their varying 
quantities of fatty acids. 
Rochleder * analysed a specimen of fraxetine crystallized several 
times from alcohol, and obtained numbers which he expresses 
by the relation C*? H* 0%, But-the numbers found by Roch- 
leder agree better, as Wurtz suggests t, with the formula 
* Poggendorff’s Annalen, May 1859. 
Tt Répertoire de Chimie, September 1859. 
Phil, Mag. 8. 4. Vol. 19. No. 124. Jan. 1860. K 
