12 MATERIA M'EDICA. 



^yaporable except in a high degree of heat,, 

 were termed fixed : and ammonia, being 

 evaporable in alow temperature, obtained 

 the name of volatile alkali, 



ALKANET ROOT. The only use of 

 this root, is to give an elegant red colour to 

 oils and ointments. 



ALOES. This is the inspissated juice of 

 certain plants of the same name, and the 

 most effectual purgative for horses we are* 

 acquainted with; It is of an intensely bitter 

 ta^te, and of a strong, unpleasant odour. 



The different sorts of aloes are distinguish- 

 ed by the names of the places whence they 

 are brought- 



SuccoTRiNE Aloes^ is brought from the 

 island Socotra, in the Indian ocean, and is 

 supposed to be more safe in its operatioir 

 than the pther kinds. It is of a dark, red- 

 dish, or brown colour, quite opaque, and 

 has a less disagreeable smell than the others;; 

 it sells at a high price, and' is therefore not 

 unfrequently adulterated. I have been so 

 often disappointed in the effect of succottin€ 

 aloes, or rather what is commonly sold' 

 undor that niame, that I now always use the 



