236 IRRITABILITY 



been obtained for the analysis of this group of reactions. With 

 the closer study of the process of excitation the facts in connec- 

 tion with the refractory period and fatigue make it necessary 

 that the processes of depression be taken into consideration. 

 Toxicology and pharmacology likewise furnish innumerable 

 effects of depression produced by poisons and drugs. Unfortu- 

 nately the investigation of these reactions has been in the main 

 purely superficial. This arises from the recency of the devel- 

 opment of these sciences. Even later than physiology they are 

 only now beginning to extend their investigations, directed up to 

 the present to the grosser organic reactions, to the cellular analysis 

 of the effects of poisons. How rarely we find instances in which 

 the effect of some drug is studied at the point of attack and sys- 

 tematically followed to the specific cell form, and its primary 

 excitating or depressing effect on this or that constituent process 

 of the metabolic activities ascertained. And how great, on the 

 other hand, is the number of "medicines" making their appear- 

 ance each year in pharmacology of which nothing further is 

 known than a few secondary effects on the action of the heart, 

 the blood pressure, the secretion and excretion and on some other 

 outwardly perceptible organic actions ! This deplorable condition 

 of present-day pharmacology must be ascribed to the regrettable 

 circumstances that pharmacological research is only in a very 

 small degree the result of careful investigations, carried out by 

 biologically and chemically trained pharmacologists, but is for 

 the most part undertaken at the instigation of chemical manu- 

 facturers. This eager haste to obtain superficially practical 

 results has lessened in great degree the interest in the close and 

 painstaking theoretical analysis of reaction to poisons. Thus it 

 happens that, in spite of the numberless examples of the depress- 

 ing effects of poisons discovered by pharmacologists, it is only 

 in rare instances that the physical nature of these processes is 

 more closely studied. Therefore, investigation in pharmacology 

 and toxicology in so far as they are carried out in a purely 

 scientific spirit and not influenced by the desire for merely super- 

 ficial results, may find here a wide field of research work, rich 

 in future promise. It is from such investigation that we may 



