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elevated ; which he could ascribe to no other cause 

 than to its having dissolved sugar and mucilage, 

 which had been stored up through the winter. 



He examined the alburnum in different poles of 

 oak in the same forest : of which some had been fel- 

 led in winter, and others in summer ; and he always 

 found most soluble matter in the wood felled in win- 

 ter, and its specific gravity was likewise greater. 



In all perennial trees this circumstance takes 

 place ; and likewise in grasses and shrubs. The joints 

 of the perennial grasses contain more saccharine and 

 mucilaginous matter in winter than at any other sea- 

 son ; and this is the reason why the fiorin or Agros- 

 tis alba, which abounds in these joints, affords so use- 

 ful a winter food. 



The roots of shrubs contain the largest quantity 

 of nourishing matter in the depth of winter ; and the 

 bulb in all plants possessing it, is the receptacle in 

 which nourishment is hoarded up during winter. 



In annual plants the sap seems to be fully ex- 

 hausted of all its nutritive matter by the production of 

 flowers and seeds j and no system exists by .which it 

 can be preserved. 



When perennial grasses are cropped very close 

 by feeding cattle late in autumn, it has been often ob- 

 served by farmers, that they never rise vigorously 

 in the spring ; and this is owing to the removal of 

 that part of the stalk which would have afforded them 

 Concrete sap, their first nourishment. 



Ship builders prefer for their purposes that kind 

 of oak; timber afforded by trees that have had their 



