PHYSIOLOGICAL ACTION, AND ANTAGONISM. 
239 
latter develops in strong solution a veratria-like curve), and also that potassium is 
antagonistic to barium. 
(8) Sodium, in strong solutions, may reduce the lithium contraction before the 
death of the muscle occurs. 
Although we have at present considered the action of ammonia, compound ammonias, 
alkalies, and alkaline earths, on voluntary muscle only, we have made a number of 
experiments which seem to show that their action on involuntary muscular fibre is 
very similar, e.g., barium causes a very great prolongation of systole in the Frog’s heart, 
just as it prolongs the contraction of voluntary muscle. These results we intend to 
investigate more fully, and hope to publish them hereafter. 
All attempts to establish a relationship between atomic weight and physiological 
action have hitherto failed. It may be that this failure has resulted from the lethal 
activity on the organism, as a whole, having been taken into consideration, whereas 
different substances may cause death by acting on different structures. We think that 
by the method here pursued of investigating their relationship to one or two structures 
only, and by a careful comparison of their actions, some definite connection may yet be 
established, and we hope that the results which have been recorded may serve as a 
contribution towards this end. 
Perhaps they may also serve to throw some light on the curious subject of the 
different reactions of different organisms to the same drug, but this also we purpose 
to follow up in a further research. 
We desire to acknowledge most gratefully the great kindness of Professor Ranvier, 
who placed his laboratory at our disposal, and afforded us every facility for carrying 
out there the experiments on warm-blooded animals, and also on unpithed Frogs, 
which are rendered so difficult in this country by the present state of the law. 
Explanation of Figures. 
PLATE 8. 
The figures represent the curves obtained by registering the contraction of the 
gastrocnemius of the Frog (Rana Temporaria ) on a revolving cylinder. 
Fig. 1. Frog poisoned by 1 drop 10 percent, solution of dimethyl-ammonium chloride. 
a. Ligatured leg. 5 s tetanus, direct stimulation of gastrocnemius. 
b. Ditto. Indirect stimulation. 
c. Poisoned leg. Direct stimulation. 
d. Ditto. Indirect stimulation. 
