PREFACE 



TO THE THIRD EDITION 



THE conditions under which this, the third edition, has been prepared, 

 have been somewhat adverse. While it was considered desirable to 

 add brief accounts of a number of drugs in less frequent use, due 

 regard has had to be given to the high cost of production. A reduction 

 in the number of pages has been made possible by the use of a slightly 

 smaller type and by the omission of the classification according to 

 natural orders and of a few of the illustrations. Notwithstanding 

 this reduction in size, the number of drugs dealt with has been very 

 considerably increased, and numerous notes have been added in order 

 to increase the general utility of the work. 



All temperatures are now stated in degrees Centigrade. 



H. G. G. 



PREFACE 



TO THE SECOND EDITION 



THE present volume, published under the title of a ' Text-Book of 

 Materia Medica,' constitutes a second edition of the author's ' Intro- 

 duction to the Study of Materia Medica ' which appeared in 1899. 

 This change in title has been rendered desirable by the numerous 

 additions that have been made to the work with the view of broadening 

 its scope. To this end a chapter on the history and commerce of 

 drugs has been added. Each section has been prefaced by a short 

 introduction, including, in the section dealing with * Animals and 

 Animal Glands and Secretions,' a brief outline of modern zoological 

 classification. For the convenience of advanced students the micro- 

 scopical characters of, and assay processes for, a number of important 

 drugs have been added. The commercial varieties have been more 

 fully dealt with, and considerably more attention has been paid to 



