406 
COLOUR-TESTS FOR STRYCHNIA, ETC. 
metal, when heated so as to become luminous, give an ex¬ 
tremely ^ characteristic spectrum, which at the same time 
exhibits the remarkable simplicity of the spectra of the other 
alkaline metals. Its spectrum consists of only two blue 
lines—a weaker line, corresponding with the Blue stron¬ 
tium line, and another which lies only a little further 
toward the blue end of the spectrum, and which vies in 
intensity and sharpness of definition with the red line of 
lithium. 
Extracts from British and Foreign Journals. 
ON THE COLOUR-TESTS EOR STRYCHNIA, AND THE 
DIAGNOSIS OF THE ALKALOIDS. 
Being the substance of 'pari of the Croonian Lectures for 1861, 
delivered at the Royal College of Physicians. 
By William A. Guy, M.B. Cantab., Fellow of the College, 
and Professor of Forensic Medicine, King’s College, London. 
The observations which I am about to make on the colour- 
tests for strychnia formed part of the three Croonian Lectures 
on Tabular Analysis, given at the College of Physicians at 
the end of February and beginning of March of this year. 
In those lectures, one form of tabular analysis was illustrated 
by a table of the alkaloids, and as the construction of the 
table grew out of a series of experiments on strychnia, and 
especially on the colour-tests for that important poison, it 
was necessary to enter into some details respecting those 
tests. The questions which I proposed to myself for solu¬ 
tion w T ere the following : 
1. The best form and mode of application of the colour- 
tests, 
2. Of the colour-tests, w r hich is to be preferred ? 
3. Are the colour-tests, or is the selected test, open to any 
serious objection ? 
4. Is it possible by means of the colour-tests, or by any 
simple modification of them, to distinguish the alkaloids from 
each other? 
