The Stem 



Here are some experimental proofs of 

 this annual formation of a ligneous layer. 

 A strip of bark is removed from a tree and 

 a thin sheet of metal is fixed on the bare wood. 

 The bark is replaced and firmly fastened, so 

 that the wound may heal. Ten years pass 

 away and we return and remove the bark 

 in the same place. The metal sheet can no 

 longer be seen, and to find it we must dig 

 into the thickness of the wood. Now, if we 

 count the ligneous layers removed before we 

 reach the sheet of metal, we shall find exactly 

 ten, the same as the number of years which 

 have expired. 



We know of a number of observations of 

 the same kind as the following one. Some 

 foresters cut down a beech, with the date 

 1750 carved on its trunk. The same inscrip- 

 tion was found in the interior of the wood, and 

 to reach it they had to go through fifty-five 

 layers showing nothing whatever. Now, by 

 adding fifty-five to 1750, we get the very year 

 in which the tree was cut down, 1805. The 

 inscription carved on the trunk in 1750 had 

 penetrated the bark and reached what was then 

 the exterior layer of wood. Since then fifty- 

 five years had passed and fresh layers, exactly 

 the same in number, had covered the first. 



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