2 INTRODUCTION. 



tinguished himself in the field of phytological in- 

 vestigation, and eminently contributed to the ad- 

 vancement of the science. But especially the name 

 of the persecuted, though perhaps prejudiced, 

 Priestly, deserves to be particularized, as being the 

 first who introduced into the study of phytology 

 AndappU-the aid of pneumatic chemistry, which, under the 

 happy auspices of Ingenhouz, Senebier,Saussure,and 

 e " ot ^ ers ^ nas done more to elucidate the phenomena 

 of vegetation, than all other means of investigation 

 put together ; so that our knowledge of the physio- 

 logy of vegetables may now be regarded as resting 

 upon the foundation of a body of the most incon- 

 trovertible facts, and assuming a degree of impor- 

 tance inferior only to that of the physiology of 

 animals. 



Leaving But although the labours of phytologists have 



desidera- been directed with success to the explication of a 



detailed* var i e ty f tne niost important phenomena of vege- 



view of tation, and although we have been already favoured 



ture of ve- with a condensed and systematic view of the result 



of their investigations by writers of the highest 



celebrity, yet there seems to be still wanting some 



work that shall exhibit them more in the detail, and 



serve the purpose not merely of a brief and rapid 



sketch to assist the recollection of the adept, but of 



a clear and copious introduction to facilitate the 



studies of the novice, by presenting to him first, 



such an elementary view of the vegetable kingdom 



in general as shall be directly preparatory to phy- 



