1 INTRODUCTION. 



ions, of colloidal metals, with an action analogous to that of 

 ferments, and of known and unknown physical properties, such 

 as radio-activity, probably enter into the action of many 

 drugs. All the phenomena of plant life are not explicable in 

 terms of chemistry and physics ; there are certain residual 

 phenomena which point to the existence of what may be called 

 in the present state of our knowledge, " vital force. "• 



It is hence, that many medical practitioners have been 

 disappointed with tinctures and other preparations of medicinal 

 plants, because such preparations did not give any satisfactory 

 results when prescribed to patients. Speaking of Oolut-Kumbal, 

 (Abroma augusta) Dr. Bhoobun Mohun Sirkar wrote in the 

 Indian Medical Gazette for May, 1900 : — 



" Attempts have been made to administer the drug in the 

 more acceptable forms of tincture, pill or powder, but none prove 

 so efficacious as the fresh viscid sap in substance in which form 

 I have used it with wonderful results." 



It is well-known that the people of India use the juice of fresh 

 vegetables for medicinal purposes. But on chemical analysis, 

 these vegetables do not yield any peculiar chemical substances to 

 which their curative virtues could be justly attributed. It has 

 been the tendency of late, therefore, to disapprove the use of 

 such vegetable remedies. A well-known medical man writes in 

 Allbutt's System of Medicine : — 



" The chemical composition of a drug is not unfrequently 



the key to its pharmacological action If a drug have 



no active properties, it is surely devoid of medicinal effect unless 

 it be a food ; for medicinal action is the outcome of the effects of 

 active principles on tissues. It is always possible that in any 

 particular drug the active medicinal agent may have escaped 

 notice ; but in the present state of chemical science it is not 

 likely that undiscovered principles reside in such substances 

 as sarsaparilla and hemidesmus : yet these drugs are given on 



•Biochemistry of plants and animals has not yet been fully investigated. 

 We do not know even much about the function of enzymes, regarding which 

 two views are held one that they are a property and the other that they 

 are a substance. Chemistry cannot produce them. They are found only as 

 the products of protoplasm of living cells. It may be that many processes 

 taking place in living cells are the results of Enzyme activity. 



