324 



Drs. T. L. Brunton and J. T. Cash. [June 21, 



Pn 7T On 



n. £ = Jl^. vers — e=JJL. 



2 n n 2 



2 p x -5 /a x "25 



3 -25 -115 



4 -146 -062 



5 -095 -040 



6 -067 -027 



7 -051 -020 



Figs. 5 and 6 show the hypotrochoids corresponding to the values of 

 e in the first column, and figs. 7 and 8 those in the second, for n=2 

 and n=4i. 



There are some propositions relating to the form of cylindrical 

 turned surfaces which have an analogy to that considered in this 

 paper. These I hope to examine in a future communication. 



YI. " Contributions to our Knowledge of the Connexion be- 

 tween Chemical Constitution, Physiological Action, and 

 Antagonism." By T. Lauder Brunton, M.D., F.R.S., and 

 J. Theodore Cash, M.D. Received June 13, 1883. 



(Abstract.) 



This paper is divided into several parts. In the first the authors 

 consider the general action of ammonium salts, and show that the 

 action of the ammonium is considerably modified by the acid radical 

 with which it is combined. 



All the ammonium salts affect the spinal cord, motor nerves, and 

 muscles, and in advanced poisoning tend to poison all those structures. 

 The course of poisoning varies with the salt employed. The chloride, 

 bromide, and iodide form a series in which a stimulant action on the 

 cord is best marked in the bromide, and the paralysing action upon it 

 and upon motor nerves most strongly in the iodide. 



Motor nerves are also paralysed by the sulphate and phosphate, 

 though less strongly than by the iodide. 



The iodide tends to arrest the circulation sooner than the other 

 salts. 



Ammonium bromide appears to have a special tendency to cause 

 coagulation of the stroma of red blood corpuscles. The sulphate 

 does so to a less extent, and the phosphate and iodide have a still 

 less effect. 



In the second part the action of salts of compound ammonias was 

 investigated. The substances employed were ethylamine, trimethyl- 

 amine, and triethylamine ; the chlorides, iodides, and sulphates of amyl 



