ALOES. 83 



rasped. Colour, not so lively ; odour and taste, similar to the other ; 

 the perforation extends quite through, and sometimes presents the 

 remains of the string upon which it was dried ; inferior in value, but 

 much cheaper. 3." European Rhubarb. — Comes in long thin pieces, 

 more compact ; does not tinge the saliva, nor feel gritty to the teeth ; 

 inferior to the others as a purgative. 



Active principle, vAw6a;'6eW^2, — a yellow, crystalline, volatile sub- 

 stance ; contains also tannin, oxalate of lime, colouring matter, &c. 

 Water and alcohol extract its virtues ; should not be long boiled. 



Uses. — A good tonic cathartic, operating chiefly on the peristaltic 

 motion ; does not deplete, and hence the best purgative in typhoid 

 cases. Much used in constipation, combined with aloes and soap. 

 It sometimes gripes, in which case it may be combined with aro- 

 matics. Dose, as a laxative, 5 to 10 grains ; as a purgative, 20 to 

 30 grains ; given in powder or pill. The following are the officinal 

 preparations : — Ivfusiim Rhei, made in the proportion of 3ij to Oj 

 water ; Tinctura Rhei^ useful in typhoid complaints / Tinct. Rhei 

 et Aloes^ formerly called Elixir tSacrum ; Tinct. Rhei et Gen- 

 tiama ; Tirict. Rhei et Se7i7ice, or Warner^ s Gout Cordial; 

 Syrupus Rhei ; Syrupus Rhei Aromaticus, or Spiced Syrup of 

 Rhubarb ; Syrupus Rhei et Sennce. — Roasting impairs the purga- 

 tive property of rhubarb, but does not affect its astringency. 



Aloes. — (Aloe, U. S.) 



Inspissated juice of the leaves of different species of aloe, as A, 

 spicata^ A. Socotrina and A. vulgaris, — succulent plants with long, 

 narrow-toothed leaves, growing in tropical countries. The juice is 

 procured either by draining from the leaves, by expression, or by 

 boiling. Several varieties recognised in commerce : 1. Cap)e Aloes. 

 Obtained from the A. spicata, growing at the Cape of Good Hope ; 

 occurs in masses of a shining, dark olive-green colour, of a vitreous 

 fracture, translucent at the edges ; powder, of a greenish-yellow 

 colour ; odour, disagreeable ; taste, intensely and permanently bitter. 



2. Socotrine aloes, — from the A. Socotrina; pieces of a yellowish- 

 brown colour, less shining than the former; fracture conchoidal ; 

 odour, aromatic ; taste, very bitter ; much the most valuable variety, 



3. Barbadoes aloes, — prepared in the West Indies; the product chiefly 

 of the A. vulgaris; colour dark-brown, not shining ; odour disagree- 

 able ; much used for horses. 4. Hepatic aloes, — known in India as 

 Bombay aloes; probably an inferior variety of Socotrine and other 

 sorts ; it has a dark liver colour. 



Aloes consists of a peculiar soluble matter termed oloesin, and an 

 insoluble substance called apotherrie. It yields its virtues to water 

 and alcohol. 



JJses. — A warm purgative, slow in its operation, acting on the 

 lower bowels ; will sometimes produce piles, if too long continued ; 



