330 POISONS, CONTAGIONS. MIASMS. 



Such substances are not poisons in the limited 

 sense of the word, for their injurious action depends 

 merely upon their condition. 



The action of the proper inorganic poisons is 

 owing, in most cases, to the formation of a chemical 

 compound by the union of the poison with the 

 constituents of the organ upon which it acts ; it is 

 owing to an exercise of a chemical affinity more 

 powerful than the vitality of the organ. 



It is well to consider the action of inorganic 

 substances in general, in order to obtain a clear 

 conception of the mode of action of those which 

 are poisonous. We find that certain soluble com- 

 pounds, when presented to different parts of the 

 body, are absorbed by the blood, whence they are 

 again eliminated by the organs of secretion, either 

 in a changed or in an unchanged state. 



Iodide of potassium, sulpho-cyanuret of potas- 

 sium, ferro-cyanuret of potassium, chlorate of pot- 

 ash, silicate of potash, and all salts with alkaline 

 bases, when administered internally to man and 

 animals in dilute solutions, or applied externally, 

 may be again detected in the blood, sweat, chyle, 

 gall, and splenic veins ; but all of them are finally 

 excreted from the body through the urinary pas- 

 sages. 



Each of these substances, in its transit, produces 

 a peculiar disturbance in the organism in other 

 words, they exercise a medicinal action upon it, but 

 they themselves suffer no decomposition. If any 



