208 
THE BEAVER. 
ture of the spot from which the mud 
taken. As soon as any part of the materia^ 
is placed where it is intended to remain, the)' 
turn round and give it a smart blow with 
tail. They strike the same sort of blow up®^ 
the surface of the water when they are goin^ 
to dive. 
Late in the autumn, after the frosts ha''^ 
begun, the outside of the hut is covered 
plastered with mud. The frost soon render® 
it almost as hard as stone, effectually exclud' 
ing their great enemy, the wolverine, duriHr 
the winter. Their habit of walking frequently 
over the work during its progress has led t^’ 
the absurd idea that they use the tail as ^ 
trowel. The habit of flapping with the tail' 
which, unless it be in the act already mention' 
ed, does not appear designed to affect any 
particular purpose, is retained by the beavn^ 
in a state of captivity. The houses, vfhe^ 
they have stood for some time and been kepi 
