238 NEW TEST LIQUOR FOR ACIDS AND ALKALIES. 
ART. XLVX— NEW TEST LIQUOR FOR ACIDS AND AL- 
KALIES. By J. Marsh. 
The infusion of the common red cabbage has been long in 
use in the chemical laboratory, as a test to distinguish acid 
from alkaline bodies when in solution ; and although possess- 
ed of great delicacy in this respect, is still subject to an objec- 
tion, on account of its becoming so exceedingly offensive in 
its smell, after having been prepared a few months. 
In order to obviate this objection, I undertook some experi- 
ments, about two years ago, on the coloring matter of the 
dark red hollyhock, the purple radish, and the dark red beet 
root ; but during my experiments, I found many objections to 
all. The beautiful blue color of the dark red hollyhock, ob- 
tained by alcohol, is, however, worthy of notice; but I have 
not had time to look much to it during my experiments on 
this subject, my attention being forcibly drawn to the 
beautifully colored infusion obtained from the dark varieties 
of the dahlia, such as the Conqueror of Sussex, Sir Edward 
Codrington, Sir E. Sugden, Alman's Splendissima, Parson's 
Rival, Brown's Ion, Holme's Rival, Sussex Lima, Metropo- 
litan Perfection, Pasha of Egypt, Robert le Diable, and 
Sambo, — these being the varieties that I have mostly employ- 
ed; there are many more equally good, but they have not 
fallen in my way. 
This infusion is easily obtained as follows : — Into an infu- 
sion pot, or any common earthen vessel, let as many of the 
petals of the above named dahlias be lightly pressed, and then 
boiling hot distilled, or good rain water, sufficient to cover the 
petals about an inch, be introduced. The best method of 
keeping them down, is by means of a piece of plate glass or 
the foot of a broken tumbler, or even a piece of common por- 
celain will do very well. The whole may be kept on the 
hob of a common fire place, simmering for two or three hours, 
covered over with a piece of common paper, to keep out any 
dirt which might otherwise fall in. The liquor is then to be 
