24 THE BIOLOGY OF DAILY LIFE. 



long-established horrors of opium ; loss of memory, 

 from the use of bromide of ammonium, and such 

 Lethean potions ; the disintegration and rotting of the 

 bones from mercury, and the special necrosis of the 

 lower jaw from phosphorus, and, to mention smaller 

 evils, the many sharp pangs of toothache, which, all 

 unsuspected, follow the use of the seemingly harmless 

 phosphates given as tonics, or as so-called " Chemical 

 food." 



But we must get on. 



In the category of drugs we are obliged to include 

 not only all the medicines in ordinary use, but also all 

 substances (such as mineral salt and baking-soda) 

 added to our food, and not in an already organized 

 condition ; besides these, many of the condiments 

 which, though of vegetable composition, were either 

 originally unfit for human food, or are rendered unfit 

 by the treatment and adulteration to which they have 

 been subjected.* 



One special and invariable characteristic of a true 

 medicine is, that it must not be a drag. It must be 

 completely eliminated from the system in a day or two 

 at the most. It must prove that it does so, BY SETTING 

 UP NO HABIT. This simple test one can use and apply 

 on and for himself. The doses of a true medicine 

 become if anything smaller, a greater effect is accom- 

 plished by a diminished dose, as the condition which 



* We are thankful, however (see Chapter viii.), that we are 

 delivered from many absurd restrictions, founded on the mis- 

 taking the active manifestation of Nature's efforts after recovery 

 for symptoms of disease. We are left everything that a natural 

 taste pronounces " good." 



