TRANSLATOR'S PREFACE. 



Soon after the publication in German of Professor Dragendorff's 

 ' Pflanzenanalyse,' it was suggested to me that an English translsi- 

 tion of the work would supply a want keenly felt by both English 

 chemists and English pharmacists. 



A thorough knowledge of the German language and a practical 

 acquaintance with many of the processes described, gained whilst 

 a pupU in the author's laboratory, would, it was thought, enable 

 me to offer a translation of trustworthy accuracy ; and this has 

 been my endeavour. Such alterations or additions as have been 

 considered needful have been made in the text, the proof-sheets 

 of which have been submitted to the author. 



Most of the references have been checked, as accuracy in this 

 particular was deemed very important. To many of them, how- 

 ever, access could not easily be had ; but it is hoped that even in 

 these cases very few will be found to be incorrect. To secure to 

 English readers the usefulness of the numerous quotations, refer- 

 ence has been frequently made, in brackets, to abstracts or trans- 

 lations that have appeared in English journals. 



One word has been employed in a somewliat unusual sense. 

 The solution obtained by treating a substance with spirit is called 

 a ' tincture,' with cold water an ' infusion,' and so on. All such 

 solutions have been included in the general term ' extract ;' the 

 latter will not, therefore, necessarily mean the dry residue com- 

 monly called 'extract.' 



The name ' petroleum spirit ' sufficiently indicates the origin of 



