168 
ON ARNICINA. 
action of caustic alkalies, and are, consequently, not to be ob- 
tained by either of the above methods ; as for example — hyos- 
cyamia, daturina, atropina, aconitina, and lobelina. Some of 
these are volatile and others non-volatile, and they also vary 
considerably with respect to the degree of their solubility in 
water. But they all agree in one important point, viz. that they 
can be extracted from their sources by the process which I have 
previously described for obtaining lobelina. 
My object in endeavouring, however imperfectly, to give a 
concise account of the discovery of organic bases, and the 
methods for their extraction, is to invite the attention of British 
pharmaceutists to an extensive and important field of inquiry, 
and to the precautionary measures required in searching for 
alkaloids amongst the numerous potent members of the vege- 
table kingdom, although not altogether to discard the old methods 
for their detection ; yet when they fail to prosecute their re- 
searches by the more recent ones, and even when both are 
ineffective to devise methods for themselves. It may be 
mentioned to shew the facility of the process to which I have 
endeavoured to call attention, as well as the no doubt ex- 
tensive results which may be secured by it, that, in addition to 
the isolation of lobelina, I have obtained strong indications by 
it of organic bases in Spigelia anthelmintica, Aristolochia ser- 
pentaria, besides the organic base arnicina, from Arnica mon- 
tana, which the chief object of the present paper is to describe. 
Arnica montana, although not extensively used in this country, 
is held in high estimation by the medical profession in Germany 
as an effective remedial agent. It is known to exercise a power- 
ful and defined action on the animal economy. The flowers and 
other parts of this plant have several times been chemically 
examined, and their virtues have been generally ascribed to an 
acrid resin which they contain. But there has been much doubt 
expressed as to whether this resin was really the active principle; 
for Professor Pfaff, of Kiel, observes, “ Arnica flowers is one 
of those agents whose chemical composition and therapeutic 
powers, which depend on the former, are enveloped in obscurity.” 
Dr. A. T. Thomson has recorded his belief that he had de- 
tected igasurate of strychnine in the flowers. This statement 
induced Versmann, at the suggestion of Pfaff, to institute an 
inquiry by direct experiment as to its correctness. The result 
was that he has proved the absence of any compound of 
strychnine in them. My experiments bear testimony to the 
truth of his conclusion in this matter, while I differ entirely from 
him in another one, that in which he denies the existence of any 
alkaloid in this plant. But it is not altogether surprising that 
he should have overlooked the presence of an organic base in 
