48 M. Hlasiwetz on Quercitrine. 
equation P+Q “” —1=0, being equivalent to P=0 and Q=0, 
proves that there are values of z and y which make P and Q 
vanish simultaneously ; and it only remains to show that they 
can be found, which may be simply done as follows. From the 
equations P=0 and Q=0, one of the unknown quantities z and 
y may be eliminated by a direct process; and as it has a real 
value, the resulting equation has areal root. Consequently, the 
original equation being given with numerical coefficients, this 
root and the corresponding value of the other unknown quantity 
may be found by approximate methods. Thus the possibility of 
finding a root, real or imaginary, of any proposed numerical 
equation is demonstrated. 
Cambridge Observatory, 
December 21, 1859. 
IX. Chemical Notices from Foreign Journals. By i. ATK1NsoNn, 
Ph.D.,F.C.S., Teacher of Physical Science in Cheltenham College. 
[Continued from vol. xviii. p. 459.] 
UERCITRINE, the colouring matter first discovered by 
Chevreul in quercitron bark, has since been found to be 
contained in a great number of plants of different orders ; among 
others Rochleder has found it in the horse-chestnut. Rigaud 
found that it belonged to the class of glucosides, and was capable 
of being decomposed into grape-sugar and quercetine. 
C58 F120 0344 HO =C!? HO} + 646 HIE Q20, 
Quercitrine. Glucose. Quercetine. 
Hlasiwetz* has now found that quercetine itself can be re- 
solved into two substances, one of which is a saccharoid matter, 
and the other is a weak acid. Quercetine is boiled with a 
concentrated solution of potash for some time, the mass then 
diluted with water, and filtered off from a floceulent substance 
which forms, the nature of which from its small quantity could 
not be determined. The solution is then evaporated to dryness, 
extracted with alcohol, the alcoholic solution distilled off, and 
the residue dissolved in water. To the solution, sugar of lead is 
added, which causes a copious precipitate. 
The solution filtered off from the lead precipitate, and evapo- 
rated, deposited after some time crystals which, by analysis and 
from their properties, were identified with phloroglucine, the 
saccharoid substance formed as a product of decomposition of 
phloretine f. 
The precipitate produced as above by acetate of lead is mixed 
* Liebig’s Annalen, October 1859, + Phil. Mag. vol, xi. p. 203, 
