BISET OR WILD ROCK-PIGEON. 
149 
vantages not possessed by the square, giving an 
easier access to the breeding birds to their nests, 
and a gi'eater facility of taking the young, and in- 
specting and clearing out the holes, by means of a 
ladder turning upon an axis. Around the interior 
of the tower, about three or four feet from the bot- 
tom, a horizontal ledge of eight or ten inches in 
width ought to project, in order to prevent rats, 
weasels, and other vermin, destructive to the eggs 
and young, from scaling the walls and entering the 
pigeon-holes, and if this ledge be covered on its un- 
der surface with tin or sheet-iron, it will the more 
effectually prevent the entrance of such intruders. 
A second lodge of less width, and about midway up 
in a pigeon-house of considerable height, may also 
be of advantage, not only for additional security 
against enemies, but as a resting-place for the pigeons 
when they enter the house. The holes or nests are 
best built in quincunx order, and not directly over 
one another, and they ought to be sufficiently large 
to allow the old birds to move in them with freedom, 
and to stand upright, in which position they always 
feed their young. 
Frequent attention to the state of the holes is ne- 
cessary, and they ought regulai-ly to be inspected 
and cleansed after each great flight, that is, towards 
the end of May, and again before winter. The 
dung accumulated at the bottom of the house should 
also be removed every three or four months, as the 
effluvium which arises from it when in a large mass. 
