72 



Dr. Wight on the Cassia Burmanni. 



[July 



appertaining to the objects of the Madras Journal, than to one exclu- 

 sively devoted to medicine. 



The report, which appears to have for its object that of showing the 

 course to be pursued in forming an Indian Pharmacopoeia, has not yet, 

 so far as 1 have learned, reached Madras, and as the notice I have seen 

 does not mention the measures which the Committee propose to pursue 

 for the improvement and extension of our knowledge of that depart- 

 ment, my remarks and suggestions will be entirely confined to it. 



A cursory retrospect of the history of Materia Medica is sufficient to 

 satisfy any one, however slightly conversant with the subject, that to 

 complete a work of the kind contemplated by the Committee, of even 

 moderate pretensions, is a task of great difficulty, owing to the many 

 sources of error by which it is beset ; and such a work can only be rais- 

 ed to the first rank, by the slow accumulation of experience, resulting 

 from repeated experiment and observation, carefully distinguishing, at 

 every step, between the jarring coincidences of post hoc and propter hoc : 

 the result of which, in many instances, will be, to discard, as inert, me- 

 dicines which have long enjoyed unmerited reputation, the removal of 

 each of which must be esteemed an advance towards perfection. 



The Hindoo Materia Medica, like that of all other nations but little 

 advanced in civilization, is no doubt loaded with many such unworthy 

 articles, but probably not much more so than those of Europe were two 

 certuries ago ; of these some may at once be struck out ; others, how- 

 ever, can only be removed by the tedious process above specified. On 

 the other hand it embraces many medicines of vast activity, but with 

 whose powers, and the methods of administration best suited to elicit 

 them, we are yet comparatively unacquainted. To detect error in the 

 cue case, and to ascertain the existence of valuable properties in the 

 other, the same course must be followed, and not by one man, or in 

 one place, but by many, and in different situations, each, moreover, mak- 

 ing sure that he is experimenting on the same plant. 



This last precaution is of greater importance than some might sup- 

 pose. I have repeatedly had wrong plants brought to me, when I had 

 no other means of making known the one wanted, than by reference to 

 the native name assigned in Ainslie's Catalogue, and I have also seen 

 two persons sent in different directions for the same plant, bring differ- 

 ent ones, each insisting that his was the true one, and some times both 

 at variance with the systematic name given as the synonym. I know 

 an instance where a gentleman experimented most perse veringly with 

 the common physic-nut (Jatrophacurcas) on the supposition that it was 

 the true Croton tiglium, being brought to him by his dresser as the 

 plant so named in Ainslie's Materia Medica. The very same thing 

 happened to myself and on the same authority ; I simply put the book 

 into my native dresser's hand, made him read the name, and asked him 



