VINEGAR. 179 
alkalies preserve its colors. It forms with different 
metallic oxides, red and orange lakes. 
“The stuffs, with the use of mordants, take on various 
tints of yellow and of orange, brown, and rose color It 
is obtained at the same time as the red matter, and re- 
mains in solution in the different liquids where the 
purpurholcine is precipitated; but it is not pure, and is 
mixed with the red matter. The best process to isolate 
it, is to make use of potash. It can be purified, by 
making use of the process indicated by Kullmann, for 
the yellow matter of the madder which this chemist has 
named Xanthine. Thus the seeds of the sorgho contain 
two coloring matters, which applied to dyeing, can re- 
place madder and give all the shades which are ob- 
tained from the roots of this plant. The purpurhol- 
cine differs from the red matters of the madder by its 
non-volatility. The Xantholcine seems identical with 
the Xanthine.” 
Dr. Sicard’s process having been made public, has 
created considerable interest in the city of Lyons among 
the large silk manufacturers, and experiments are being 
made to test the value of his coloring matters, the result 
of which will settle the question as to its practical 
utility. 
CEROSIE ; OR, THE VEGETABLE WAX ON THE STALKS OF THE 
SORGHO. 
In a previous place, I mentioned that as the plant ap- 
proaches maturity, a white efflorescence makes its ap- 
pearance upon the outside of the stalks, accumulating, 
