704 
OBSERVATIONS ON STRYCHNIA. 
ascertained by filtering it through paper, and applying a 
minute drop of the filtrate to the tongue, when an intensely 
hitter taste is experienced. This character of the poison is 
manifested by an aqueous solution of it containing 3 y,-J- 5 - 5 th, 
and, according to some authorities, even ^ th part of 
its weight of strychnia. By careful investigation it has 
been determined that one part of strychnia requires 6667 
parts of cold water, and 2500 of hot water, for its solution. 
3. It is pretty readily dissolved by ordinary spirit of wine, 
but only slightly soluble in absolute alcohol, ether, and 
chloroform. 
4. It is freely dissolved by dilute hydrochloric, sulphuric, 
and acetic acids, forming solutions containing compounds of 
the alkaloid with these acids, and from which strychnia is 
precipitated by solution of ammonia, potash, soda, and their 
carbonates. 
5. Perfectly pure strychnia dissolves in strong nitric acid 
without undergoing any marked change, but the alkaloid ordi¬ 
narily met with is turned of a red colour by this reagent, 
owing to the presence of brucia. 
6. In concentrated sulphuric acid strychnia dissolves, appa¬ 
rently without change, and produces a solution which should 
be examined in the following manner:— 
Place a few drops of the sulphuric acid solution on white 
porcelain, and add to it a small fragment of bichromate of 
potash. The mixture will rapidly assume a beautiful rich 
blue colour, which soon turns to purple, violet, red, and, 
in this case, in which bichromate of potash is employed, 
finally to green. ' 
If other portions of the sulphuric acid solution be sepa¬ 
rately treated with minute quantities of ferricyanide of 
potassium, peroxide of lead, binoxide of manganese, and 
permanganate of potash, in each case a series of colour- 
changes will be observed similar to those above recorded. 
In the hands of incautious or inexperienced experimenters 
incorrect conclusions may be drawn from the results of the 
application of these colour-tests when bichromate of potash, 
ferricyanide of potassium, or especially when permanganate 
of potash is employed in the detection of very small quanti¬ 
ties of strychnia, as they themselves impart a red or purple 
colour to the mixture. To avoid false deductions from such 
possible causes of error, in cases of doubt the peroxide of lead 
test should be had recourse to, as in such instances this 
reagent, being insoluble in the cold sulphuric acid, does not 
impart colour to the mixture unless strychnia be present. 
It may be here remarked that the production of colour 
