tyj FORCING OF PLANTS. 



jus. The vegetables of eokl climates, on the 

 contrary, support a much greater degree of 

 cold without injury, at least while in a tor- 

 pid state ; for when their buds begin to ex- 

 pand they become vastly more sensible, as 

 is but too frequently experienced in the fickle 

 spring of our climate. Nor is this owing, 

 as vulgarly supposed, merely to the greater 

 power of the cold to penetrate through their 

 opening buds. It must penetrate equally 

 through them in the course of long and 

 severe winter frosts, which are never known 

 to injure them. The extremely pernicious 

 effects therefore of cold on opening buds can 

 only be attributed to the increased suscepti- 

 bility of the vital principle, after it has been 

 revived by the warmth of spring. 



The vegetation of most plants may be 

 accelerated by artificial heat, which is called 

 forcing them, and others may, by the same 

 means, be kept in tolerable health, under a 

 colder sky than is natural to them. But 

 many alpine plants, naturally buried for 

 months under a deep snow, are not only ex- 

 tremely impatient of sharp frosts, but will not 

 'bear the least portion of artificial heat. The 



