How Hollow Trees are Produced 383 



it deal with the languages as a means of developing the 

 mind. It would regard these rather as necessary aids in the 

 pursuit of other knowledge, from which such training would 

 not be omitted. 



HOW HOLLOW TREES ARE PRODUCED. 



Scattered over the country, one here, and one there, in 

 not a few places, there occur hollow trees of great age. They 

 are almost always oaks, but in some instances, and especially 

 on the Continent, they may be chestnuts. : f There is always a 

 doorway of entrance and the space inside is often sufficient to 

 accommodate [several persons. They are lined with dry and 

 dead wood, but their exterior is still living and produces every 

 summer its growth of new shoots. They are the favourite 

 resort of the children of the neighbourhood, who*use them as 

 huts. 



There has hitherto been much mystery as to how these 

 hollow trees have been formed. Nothing is' less probable than 

 that the heart-wood of a large oak should undergo decay 

 whilst its outside remained sound. Even if that were con- 

 ceivable, how explain the breaking through on one side to 

 form ^the doorway ? There need, we'think, be no longer any 

 difficulty in the matter. The facts which we have recorded at 

 p. 204 give us the explanation. The conditions are conse- 

 quent upon the tree having been struck by lightning when 

 comparatively young. The effect of this would be to kill 

 the middle parts of the bole and to tear through the bark on 

 one side. After this the trunk would [slowly break up and 

 in the course of years would be removed. Meanwhile, fresh 

 layers of wood would be laid on outside [and the tree would 

 grow in girth. On the side where the bark had been torn 

 up the doorway would remain. We have but to suppose a 

 long series of years and the whole would be achieved. 



