EXPERIMENTS BY BARKING. 347 



riment was made upon a branch of a Walnut-tree, which threw out 

 leaves, &c, but lost the leaves by the latter end of August, which was 

 much sooner than the other branches did, and it became dead that 

 winter ; so it did not live so long as the Laburnums. So far as to the 

 effects of barking all round upon the Laburnum and Walnut. 



In those trees which live at the barked part, and therefore live 

 beyond the part barked, nothing particular happens respecting the 

 mode of throwing out their leaves, branches, or flowers ; but other cir- 

 cumstances take place. The Scotch Fir, Plum, Pear, Apple, are not 

 killed by being barked all round ; but a very curious circumstance 

 respecting the vegetable economy takes place, the facts relative to 

 which I shall now describe. 



In those trees which do not die upon being barked, we see the three 

 following facts : — first, I find that, if barked all round, the part beyond 

 grows in general as fast as if it had not been barked, while the part 

 between the root and barked part grows but very little ; so that we 

 shall often see a thick part above, and it shall become small all at once : 

 secondly, all that part of the tree above the circular barked part (fig. 2, a), 

 not only grows as if nothing had been done, but it grows faster in thick- 

 ness near to the barked part (fig. 2, b) than in any other part, and much 

 faster than if it had not been barked: and thirdly, the increase of the 

 new layers over the barked surface to cover it, is much thicker, and 

 makes a much quicker progress on that side beyond the barked part 

 (ib. b) than on the side next to the root (ib. c) ; indeed, it hardly makes 

 any progress at this part at all. 



The foregoing facts explain much more of the vegetable economy than 

 any other circumstance attending vegetables. We may first observe, 

 from the circumstance of the tree dying, but not immediately, beyond 

 the barked part, in consequence of its dying at the barked part, that 

 the nourishment of the tree is carried through the wood and not by 

 the bark (at least alone). But the three facts last mentioned, respecting 

 the growth of the part beyond the barked part in those which do not 

 die at the barked part, are still more curious ; for the disproportion in 

 the growth of the two parts is a very remarkable fact. It shows that 

 by barking a tree all round, the intelligence between the two parts is 

 cut off, although the nourishment is carried on ; that the part beyond 

 and near to the mischief is sensible of such an injury, and sets to 

 work to repair it : and that it should be sensible of this is evident ; 

 because from this and the consequences of it, viz. the second and third 

 observations, the loss is repaired, and the intention of this repair is to 

 support all the parts above. Therefore we may assert that the part of 

 the tree beyond the barked part is conscious of the injury, conscious of 



