1868.] Dr. W. H. Broadbent on the Action of Poisons. 465 



Almost all the zoologists and botanists will, however, return in Sep- 

 tember, with a ship hired for the purpose, and the remaining party will 

 try to go further northward, west, or eastward, from the north-west part 

 of Spitzbergen, where the expedition can obtain a sufficient depot of En- 

 glish coal. We will also try to employ the brown coal of King's Bay ; 

 but I fear this supply is not to be relied upon. 



XIII. An attempt to apply Chemical Principles in explanation 

 of the Action of Poisons.'' By W. H. Broadbent, M.D. 

 Communicated by Dr. F. Sibson, F.B.S. Eeceived June 18^ 

 1868. 



(Abstract.) 



The starting-point in the inquiry has been the two following pos- 

 tulates : — 



1 . That there must be some relation between the substance administered 

 and the animal organism, on which the effects depend. 



2. That, so far as the substance is concerned, the basis of the relation 

 can only be its chemical properties, using the term in its widest sense. 



From these postulates follow certain corollaries : — 



1 . That the physiological and therapeutic action of the same substance 

 must be similar in kind. 



2. That the action of food, remedies, and poisons must be capable of 

 explanation on the same principles. 



3. That substances chemically allied should have similar physiological 

 and therapeutic actions, or any diversity found to exist should be capable 

 of explanation on chemical grounds. 



The second of these deductions is taken as a guide in the present inquiry. 

 Something is known as to the uses of the various classes of foods in the 

 economy, and of the mode in which they subserve these uses ; this know- 

 ledge may be applied in the endeavour to ascertain the mode of action of 

 poisons. 



The operations taking place in the animal organism may be divided 

 into two great classes : — (a) for maintenance of structure, (/3) for evolution 

 of force. While mutually interdependent, they are distinct, and in cha- 

 racter essentially antagonistic, structural and chemical elaboration on the 

 one hand, oxidation or disintegration on the other. 



The two great classes of food, organic and mineral, are in close relation 

 with these. The organic foods build up the tissues, but ultimately undergo 

 oxidation and yield force. The inorganic foods take a subordinate part 

 in the composition of the textures ; they do not yield force by oxidation, 

 but they influence the nutritive processes. So also the organic remedies 

 and poisons affect tlie evolution of force, mineral substances the organic 

 processes. 



(The action of mineral matters has been noticed elsewhere.) 



