INFLUENCE OF POISONS ON PROTOPLASM, ETC.HAKRIS. 107 



The following (it'scriplion of ciiiinino not written nt !il| 

 from our presentpoint of view shows that it l)elonp;s to the lust 

 mentioned group of poisons^ 



"Quinine is frecjuently ealled a protoplasm poison beeause 

 of its aetion on undifferentiated i)rotoi)lasm. In small 

 amounts it stimulates movement in Infusoria, but in larger 

 amount paralyzes these minute organisms immediately. 

 The alkaloid also retards the action of some unorganized 

 ferments, espeeialh' that of the oxidases." 



It appears, then, that all substances w^hich we may call 

 "poisons" do not act in exactly the same manner on the same 

 constituent of the vital mechanism. One might attempt a 

 classification of poisons somewhat as follows: — 



1. Substances which act b}' destroying the histological 

 integrity of the tissues altogether: strong acids, alkalies and 

 nascent elements, as CI in the "gassing" b}^ Germans. The 

 lesions may be so extensive that death results from shock 

 or from internal haemorrhage. 



2. Substances which replace O2 in air breathed or pre- 

 vent O2 gaining access to the Haemoglobin such are CO, COo, 

 and CH4. They kill by asphyxia as truly as if the person had 

 been suffocated or strangled. 



3. Substances which cause either spasm of the muscles 

 of respiration or of the diaphragm or paralysis of them, so 

 that the inspirations are suspended, no O2 reaches the tissues 

 which are asphyxiated, e. g., strychnine and allied alkaloids; 

 also curare which immobilizes muscles by making them in- 

 accessible to nerve impulses. 



4. Substances which immobilize the biogens of the neuro- 

 plasm of the central nervous system, so that consciousness 

 is ultimately abolished and the respiratory centre paralj'zed. 

 All the narcotics proper fall into this group. The vegetable 

 alkaloids are the typical members of this group inasmuch 



^The Plant alkaloids. Henry. J. and A. Churchill, 19i;3, p. 17L 



