PREFACE TO FIRST EDITION 



OWING to the role played by vegetable substances in the treat- 

 ment of disease, pharmacognosy takes rank as one of the most 

 important divisions of applied botany, as by far the great majority 

 of substances used in medicine are derived from the plant kingdom. 

 The training for this study is fundamentally botanical, and the 

 technique employed is essentially that of the plant morphologist, 

 physiologist and taxonomist. Moreover, the value of drugs depends 

 upon their constituents, and so the pharmacognocist must possess 

 a working knowledge of chemistry. He must not only be familiar 

 with plant principles in their isolated and purest forms, but must 

 apprehend their nature, combination and location in the plant. 

 Pharmacognosy, therefore, is on the one hand an applied branch of 

 botany, and on the other of chemistry. But even in this statement 

 we have only a partial view of the nature of the problems that con- 

 front the pharmacognocist, as he must be prepared to directly apply 

 the results of science to practice and assist in the solution of a great 

 variety of practical problems. The present work abounds in illus- 

 trations which show that practical pharmacognosy is dependent 

 upon the progress of scientific pharmacognosy. Among the prob- 

 lems which require the attention of the pharmacognist is the relation 

 of soil and climatic conditions to the variation in the constituents of 

 drugs, and the nature of the chemical changes that ensue in their 

 drying or curing. The problems of the pharmacognocist begin with 

 the living plant and are not entirely completed when the drug 

 reaches the retail pharmacist, as there are pharmacological questions 

 which frequently await his solution. 



At present it is becoming recognized that the pharmacognocist 

 should work in the field with the drug collector, stand at the port of 

 entry of commerce to determine what drugs are fit for use, and act as 

 the analyst for the state and Pharmaceutical Examining Boards in 

 determining to what an extent there is uniformity in the drugs and 

 preparations that have been dispensed. 



