INCONVERTIBILITY OF BARK INTO ALBURNUM, l\ 



with success, appears also, in this case, to have been over- 

 looked ; for I found, that when I destroyed the buds in the 

 succeeding winter, and left the bark which belonged to 

 thetn uninjured, this bark no longer possessed any power 

 to generate alburnum. It nevertheless contintsed to live, 

 though perfectly inactive, till it became covered by the 

 successive alburnous layers of the stock ; and it was found 

 many years afterwaids enclosed in the wood. It was, how- 

 ever, still bark, though dry and lifeless, and did not ap- 

 pear to have made niij progress towards conversion into 

 wood. 



In the course of very numerous experiments, w])ich were No facts to 

 made to ascertain the manner in which vessels are formed b™^^^ 'con- 

 in the reproduced bark*, many circumstances came under verted into al~ 

 my observation, which I could adduce in support of my °"'"""'"' 

 opinion, that bark is never transmuted into alburnum; but 

 1 do not think it tiecessary to trouble you with an account 

 of them ; foi"' though much deference is certainly due to the 

 opinions of those naturalists, who have adopted the opposite 

 theory, and to the doubts of Duharael, I am not acquainted 

 with a single experiment, which warrants the conclusions 

 they have drawn ; and I think, that, were bark really trans- 

 muted into alburnum, its progressive changes could only 

 have escaped the eyes of prejudiced or inattentive observers. 

 In the course of the ensuing spring, I hope to address to 

 you some observations respecting the manner in which the 

 alburnum is generated, 



I am, my dear Sir, 



Your most obliged obedient servant, 

 THOMAS AND. KNIGHT. 

 Elton, Dec. 29, IS07' 



* Phil. Trans, for 1807; or Journal, vol. XIX, p. 241. 



in. 



