INTRODUCTORY ESSAY. 3 



subjects worthy of fature attention. Geographical distribu- 

 tion^ and the effect of climatej soU, and exposurCj have been 

 made the objects of onr special study, and will in all cases be 

 particularly noted. "With regard to economic botany, it is 

 obviously impossible to do more than briefly enumerate, under 

 their respective species, the various products which have been 

 used in the arts : for detailed accounts of their value, we must 

 refer our readers to the many excellent works on those sub- 

 jects, which have been published by Indian botanists. 



Our work is intended to facilitate the progress of econo- 

 mists, by supplying their great desideratum, a critical descrip- 

 tion of the plants which yield the products they seek. We 

 have had a considerable experience both in medical and eco- 

 nomic botany, and we announce boldly om- conviction, that, 

 so far as India is concerned, these departments are at a stand- 

 still, for want of an accurate scientific guide to the flora of 

 that country. Hundreds of valuable products are quite un- 

 known to science, while of most of the others the plants are 

 known only to the professed botanist. The mass must indeed 

 always remain so : just as the refinements of the laboratory 

 and the calculations of the mathematician must ever be mys- 

 teries to the majority of manufacturers and navigators, whose 

 operations are based on the sciences in question. It is a mis- 

 take to suppose that it can be otherwise ; or that those who 

 are engaged in forwarding a science so extensive and abstruse 

 as philosophical botany, can command the time to become so 

 familiar with the details of the commercial value of vegetable 

 products, as to be safe referees on these subjects. On the 

 other hand, it is equally a mistake to suppose that those who 

 devote themselves to the collection of economic products, can 

 possess the experience and botanical knowledge necessary to 

 render their identifications of tropical plants trustworthy in 

 the eyes of men of science*. It is therefore as a strictly 



* For proof of this we have only to refer to the pages of any book on me- 

 dical or economic botany ; and to the fact, first indicated in these pages, that 

 the celebrated Bikh Poison, about which so much has been written, is produced 



