PERSPIRATION OF PLANTS 1J 



by the numerous subtle particles floating in the 

 air, or perhaps also by a sediment of the matter 

 of perspiration, obstructions may take place in 

 these organs j and indeed, even within a small 

 microscopical compass, several apertures are ob- 

 served to be entirely filled up with a dark coloured 

 matter. There can be no doubt, but that free 

 perspiration is, in most vegetables, as necessary to 

 their health, as to that of the animal creation. 



That moisture may likewise be conveyed through 

 the described passages into the different parts of 

 vegetables, can scarcely be denied; but whether 

 this moisture contributes to the nourishment of 

 plants, or not, remains a subject for^future exami- 

 nation. Indeed our knowledge in the physiologi- 

 cal part of botany being still so very limited, 

 and the erroneous notions carried along with it, 

 so numerous, it is to be wished that those 

 botanists who have it in their power to examine 

 the productions of the vegetable kingdom, but 

 whose minds are engrossed by terminology and 

 rage for system, would divert some part of their 

 attention to the physical department of their 



B 



