THE BIOLOGY OF DAILY LIFE. 17 



this in the short maxim, All medicines are drugs ; 



or, more accurately, All the mineral and most of the 

 vegetable medicines in common use are veritable drugs, 

 i.e., they do not pass entirely out of the system. Not 

 only does the continued use of such medicine produce 

 an altered habit of the system (this alteration evidenced 

 by increased toleration, and necessity of increasing 

 the dose to produce equal effect), but this habit is (as, 

 indeed, the etymology of the word " habit" implies*) 

 a having, or holding in the system some part of the 

 drug, which does not quite pass away. 



Some portion, even of a single dose, will remain, 

 and when the use of the drug has been long con- 

 tinued, a very serious amount is stowed away in some 

 part of the organism. For a time this seems to be 

 treated with a sort of toleration. The toleration of 

 the human body for foreign material is a very notice- 

 able thing. All constructive surgery proves that in 

 certain cases alien substances (such as artificial teeth, 

 eyes, tympanum of ear, cranial plate, and many 

 more), especially when they serve any useful purpose, 

 are tolerated by the system. They are not treated 

 like the typical " foreign body" of the older patholo- 

 gists and extradited by suppuration, but are natu- 



Galvani who had recourse to opium to relieve pain, and in thirty- 

 four years consumed two hundred weights of the crude drug, her 

 daily dose at last being two hundred grains. 



* " Habit is that which is held or retained, the effect of 

 custom or frequent repetition." Imperial Dictionary. Though 

 this suits my argument, I think it a very inadequate meaning. 

 Habit, I fancy, is rather the manner in which the whole 

 system, or any part (Body, Soul, Spirit Disposition, &c.), holds 

 itself. 



