214 LIFE OF A TREE. 
that the latter contains, besides decayed wood, 
a large quantity of various earthy and mineral 
substances, 
Unfortunately for the tree, this decay does not 
stop at the broken stump; it extends further and 
deeper into the trunk. The more limbs have 
been broken off, the more rapidly will the decay 
go on. Gradually the centre of the trunk becomes 
attacked, as being the oldest and least able to resist 
the progress of the disease. It becomes more and 
more eaten away; at first a wren built her nest 
in it, but by and by the hollow grew too large 
for her, and she shifted her quarters elsewhere. 
School-boys then found it out, and amused them- 
selves with casting heaps of stones into it. Later 
on, the hollow became the favourite hiding- 
place of children; and after this the shepherd 
took his mid-day sleep therein. So it went on, 
becoming yearly, but very slowly, more and more 
capacious, and threatening the life of the tree 
at every storm, in proportion as it weakened 
and consumed away the strength and substance 
of the wooden walls. The Frontispiece shews to 
what an extent this hollow ultimately reached ; 
for we read of the venerable tree whose portrait 
