36 Inefficiency of the Cathartic Powers of Rhubarbarine. 



of rhubarb, as a considerable portion of cathartic matter is 

 retained by solution in the water, from which the rhubarbar- 

 ine is precipitated. The term sulphate of rhubarb, is an 

 extremely erroneous application, as there is no sulphuric acid 

 in its composition. The sulphuric acid first employed in the 

 acidulated decoction, is entirely neutralized by lime, by 

 which the rhubarbarine is precipitated, perfectly uncombined 

 with acid ; it is then taken up by alcohol, which separates it 

 from the sulphate of lime. The alcohol containing the rhu- 

 barbarine is then evaporated, until the rhubarbarine is ob- 

 tained in the form above described. It is evident, therefore, 

 that from this process there can be no sulphuric acid in its 

 composition, and that the term sulphate of rhubarb is inap- 

 plicable. I employed the term sulphate of rhubarb in a for- 

 mer paper ; this was done in consequence of its having re- 

 ceived that name, a name sanctioned by custom and by 

 authors. 



The process for manufacturing the rhubarbarine is expen- 

 sive, and the product small. This renders it as costly an ar- 

 ticle as the sulphate of quinine, and on this account it is par- 

 ticularly necessary that its true properties should be known. 



The rhubarb of commerce differs materially in activity, 

 and great deception is practised, in selecting and artificially 

 preparing the roots.* From this circumstance, the same spe- 

 cies will frequently be sold under several names, such as East 

 India, Russia and Turkey, and command corresponding pri- 

 ces. There are four varieties of rhubarb indigenous in France, 

 and cultivated there; viz. the Rheum Palmatum, Compac- 

 tum, Undulatum, and Rhaponticum. The superiority of the 

 Palmatum has, however, caused the others to be neglected 

 or abandoned. The difference between the activity of the 

 French and English rhubarb and that of the rhubarb of Chi- 

 na and Turkey is caused by the age of the root. The for- 

 mer, after three years growth, decay in the ground, while the 

 latter are not taken up until the seventh or eighth year of their 

 growth. The China and Turkey varieties grow without cul- 

 ture in almost any situation, while the French and English re- 

 quire a moist soil, a particular degree of exposure, and con- 

 siderable attention in cultivation. It is necessary to plough 



* We are informed that a number of persons in London, known by the name of 

 Russitiers, gain a regular livelihood, by the art of dressing rhubarb, which they 

 do by boring, rasping and colouring the inferior kinds, for which they charge 

 eighteen pence per pound. (Paris's Pharmacologia.) 



