





348 



Of Vegetation. 



But when the cold was fo far relaxed, as 

 to have the fpirit in the firft Thermometer 

 but 5 degrees above the freezing point, the 

 fecond 8 degrees, and the 6th 13 degrees 

 tho' it was ftill very cold, yet this being 

 fome advance from freezing towards warm] 

 and there being confequently fome expan- 

 sion of the fap, feveral of the hardy vege- 

 tables grew, viz. fome Ever-greens, Snow, 

 drops, Crocus's, &c. which forward hardy 

 plants do probably partake much of the na- 

 ture of Ever-greens in perfpiring little; and 

 the motion of their fap being confequently 

 very flow, it will become more vifcous, as 

 in Ever-greens 5 and thereby the better able 

 to refill: the winter's cold : And the fmall 

 expanfivc force, which this fap acquires in 

 the winter, is moftly exerted in extending 

 the plant, little of it being wafted in pro- 

 portion to the fummer's perfpiration. 



Supported by the evidence of many of 

 the foregoing Experiments, I will now trace 

 the vegetation of a tree from its firft ferni- 

 nal plant in the Seed to its full maturity and 

 production of other Seeds, without entring 

 into a particular defcription of the ftructurc 

 of the parts of vegetables, which has al- 

 ready 



:ive 



