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ascending sap in the wood can descend or 

 bleed backwards. This is seen perpetually 

 where branches are cut off at the distance 

 of an inch or two from the stem. Their 

 diameter will be enlarged each year, their 

 ends cicatrised from the sap of the stem, 

 and a protuberance will remain ; and this 

 makes evident the unity of growth which 

 must exist at the foot of each branch, even 

 with the part of the stem above it. The 

 distance to which the descending sap will 

 ascend the descending conduits of the 

 bark of another branch or stem will 

 depend on the strength of the tide. The 

 most remarkable case of it I ever saw is at 

 Warwick Castle, on that one of the two 

 magnificent cedars between the castle and 

 the river which is next the mill. A branch 

 of about a foot in diameter (I write from 

 recollection) has been cut off at the dis- 

 tance of about eighteen inches from the 

 stem. The descending sap of the bark of 

 the stem has ascended the whole distance on 

 the upper side of this twigless and leafless 



