ON CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 



209 



Report of the Committee on the Connexion between Chemical Con- 

 stitution and Physiological Action. The Committee consists of Dr. 

 A. Crum Brown^ Dr. T. R. Fraser, andT>x. J. H. Balfour, F.R.S. 

 The investigations were conducted and the Report prepared hy Drs. 

 A. Crum Brown and T. R. Fraser. 



Drs. BEOTyy and Fkaser communicated to the Section, at the Noiwick 

 Meeting, the results of some experiments (the details of ■which have since 

 been published in the Transactions of the Royal Society of Edinburgh) on 

 the connexion between change of chemical constitution and change of phy- 

 siological actiyity. 



They haye since that time continued their investigations by applying the 

 method described in the aboye communication to the alkaloids, ati'opia, conia, 

 and trimethylamine. The substances which they have compared in refer- 

 ence to their physiological action are, atropia and the salts of methylatro- 

 pium, conia, methylconia, and the salts of dimethylconium, salts of ammonia, 

 trimethylamine, and tetramethylammonium. They have made in all about 

 120 experiments, and give in the accompanying Table the results of thirty- 

 six, in which the dose was not much above or below the minimiim fatal. 

 It will be seen that these results confirm the conclusions at which they 

 formerly arrived, viz. that the action of compounds of triatomic nitrogen is 

 different from that of compounds in which the nitrogen is stably pentatomic, 

 and that salts of ammonium bases act on the peripheral terminations of the 

 motor nerves in the same way as curara. This action, and the absence of 

 convulsant action, appear to be generic characters of the salts of ammonium 

 bases. Besides this, the salts of the ammonium bases frequently retain cer- 

 tain of the special (specific) actions of the nitrile bases from which they are 

 derived. 



Tabular Summary of Experiments with Doses that are about the 



minimum fatal. 



