370 
ON THE MELTING AND SUBLIMING TEMPERATURES 
originally contained in the ingredients employed or intentionally added, or produced 
during the process of fermentation. He alluded especially to fusel oil as a substance 
belonging to the last-named class, and stated that two drops of this oil was sufficient to 
contaminate a hundred gallons of spirit. The method of obtaining spirit in a highly 
rectified state by one operation—by the employment of Coffey’s still—was explained, 
also the means of removing fusel oil from the spirit, and of determining its strength, to¬ 
gether with many other points of practical importance and interest. 
ORIGINAL AND EXTRACTED ARTICLES. 
ON THE MELTING AND SUBLIMING TEMPERATURES OF 
THE PRINCIPAL POISONS, ORGANIC AND INORGANIC. 
BY WILLIAM A. GUY, M.B., F.R.S., 
PROFESSOR OF FORENSIC MEDICINE, KING’S COLLEGE, LONDON, ETC. 
• 
This communication does not exhaust the subject of which it treats. Its aim 
is to indicate and describe a simple method of procedure by which a new ele¬ 
ment is added to the natural history and diagnosis of poisons. It is a very ob¬ 
vious development of the method of sublimation described in previous commu¬ 
nications to the ‘Pharmaceutical Journal;’* and it will be seen to have the 
special recommendation of applying heat in so gradual a manner as to guard 
against the chief objection to Helwig 1 s plan still more completely than the 
modification I have already recommended. It may be well to add, by way of 
preventing any possible misconception of the object of this paper, that the ex¬ 
periments to which reference will be made are limited to commercial specimens 
of poisons, and to such of them as are sold as white powders or colourless crys¬ 
tals. For the alkaloids and active proximate principles I am indebted to the 
Messrs. Morson,—as I am, indeed, for almost all the preparations which I 
employ. The results of the sublimation of the alkaloids, as obtained from solu¬ 
tions of their salts, and from organic matters, must be the subject of future 
communications. 
If any excuse were needed for the present attempt to confer a more definite 
character on the test of heat as applied to poisons, it would be found in the fact 
that already, in all works on toxicology, the results of the rough method of 
procedure with the spirit-lamp and platinum-foil, or with the spirit-lamp and 
reduction-tube, are set forth with many of the poisonous substances to which 
they are deemed applicable. The following may be taken as a fair specimen of 
the description of these results as obtained with the spirit-lamp and platinum- 
foil :— 
1. Arsenious Acid. —Wholly dissipated, as a white vapour, at a temperature 
of 370°. > . _ 
2. Corrosive Sublimate. —Melts, and is wholly dissipated, without combustion 
or being carbonized, in white vapour, without residue. (No indication given 
that the poison may be sublimed prior to melting, and even without melting.) 
3. Oxalic Acid. —Melts, and is wholly dissipated. (Again no statement that 
the poison may sublime before melting.) 
4. Binoxalate of Potash. —Leaves a white ash. (No allusion to the fact that 
this poison also sublimes.) 
5. Arsenic Acid. —Not entirely volatilized. (An obviously imperfect descrip¬ 
tion of the effects of heat.) 
6. Acetate of Lead. —Leaves residue of yellow oxide with reduced metal. 
* See papers on the “Sublimation of the Alkaloids,” ( Pharmaceutical Journal’ for June, 
July. August, September, and October, 1867. 
