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which thus fail of support immediately begin to decay, 

 this is an effect always the consequence of a dimi- 

 nished supply of sap, apparent either in the leaves, 

 flower, or fruit. The disease, like every other putre- 

 faction, does not advance rapidly unless there be 

 much moisture in the atmosphere. 



The coldness of the soil causes this torpidity in 

 the action of the root ; and this, perhaps, at the very 

 period when the greatest demand is made upon it to 

 sustain the excessive perspiration which is going on 

 in the leaf, and to furnish fresh matter for elaboration; 

 to both which ends it is frequently quite inadequate, 

 owing to drenching rains. If the young fibre be 

 examined at such inclement periods, it will be found 

 somewhat discoloured ; and, in some cases, quite 

 rotten. This is not to be wondered at when the 

 habits of the plant are duly considered, and the dif- 

 ference estimated between a vine on the slope of a 

 rocky surface in the south of Europe or Asia, with 

 six inches of soil, and one in the cold northern clime 

 of Britain, in four or five feet of rich soil, every 

 breathing pore closed with a kind of alluvium. If 

 shanking were caused by sudden depressions of tem- 

 perature, why should it not occur more frequently on 

 walls out of doors, where the thermometrical changes 

 are at least as great as in doors ? Yet here it seldom 

 occurs, and here again the border is seldom so deep, 

 so rich, or so far below the surface level, as some of 



