ORDER RUBIACE^E PERUVIAN BARK. 457 



from the importation of which the Government derived a revenue 

 of about 160,000. But in 1824, the duty was lowered to six- 

 pence a pound ; and the consumption has gradually increased to 

 more than 28 million pounds, producing an import duty of 

 900,000. There are strong reasons of a moral nature for 

 encouraging the consumption of Coffee, by cheapening its price 

 to the lowest amount; for it has been satisfactorily shown that 

 the more extended use of it has mainly contributed to promote 

 improved habits amongst large classes of the community. 



628. The order Rubiacese takes its name from the Rubia or 

 Madder plant, which furnishes the most important of our crim- 

 son dyes (. 392). It is only in tropical countries, however, 

 that it presents its finest aspect ; but in some of these it is so 

 predominant, that its species constitute about l-29th of the whole 

 number of flowering plants. Amongst the most important of 

 these are the Cinchonas, which furnish the Peruvian or Jesuits' 

 Bark so largely used in medicine. This is very astringent, and 

 might be used for tanning ; but its chief peculiarity consists in 

 containing a large quantity of an alkaline substance termed 

 quinine, which may be extracted from it by chemical means, and 

 which, being the most valuable part of the drug, is now usually 

 given in a pure state. This is almost a specific for agues ; and 

 is extremely valuable as a tonic in weakened states of the system. 

 The Cinchonas, of which the several species afford this product 

 in varying degrees, grow in extensive forests in South America ; 

 chiefly inhabiting the sides of the range of the Andes, between 

 10 North Lat., and 22 South Lat., and sometimes rising on 

 these mountains to the height of 10,000 feet. It is from the 

 trees growing in elevated situations, that the best bark is derived. 

 Another most valuable remedy afforded by this order is Ipeca- 

 cuanha, which is the powdered root of a little creeping-rooted, 

 half-herbaceous plant, found in the damp shady forests of Brazil. 

 This is chiefly employed in medicine as an emetic, and also to 

 produce perspiration ; but it has several other important uses. 



629. Passing over several orders of secondary importance, we 

 come to one alike remarkable for its peculiarities of structure, for 

 the large number of plants contained in it, and for the variety of 



