56 OUR BIRD ALLIES. 
THe Sand-martin, whose small size at once serves 
to distinguish it from others of its kindred, is a bird 
of very different character, and cares nothing, one 
way or the other, for the proximity of human beings. 
Provided that it can find a sandy cliff or bank in 
which to tunnel it is perfectly contented, and there 
throughout the summer it may be seen in numbers, 
either sitting at the entrance to its burrows, or 
hawking for insects in the neighbourhood. 
Near Erith, with its immense sandpits, this in- 
teresting little bird is the most plentiful of the family, 
and I have often noticed the care with which it 
constructs its holes just out of reach of any one 
leaning over the top of the cliffs. In the railway 
cuttings, however, it seems perfectly aware that 
‘trespassers will be prosecuted,” and excavates in 
all parts of the banks, even within four or five feet 
of the ground. 
The usual depth of the burrows is from one to 
two feet, but in some exceptional instances the bird 
will penetrate for more than twice the latter dis- 
tance into the sand before it is satisfied with its 
labours. No nest worthy of the name is built, but 
at the end of the tunnel a little straw and a few 
feathers are generally collected, and upon these the 
delicate, pinky-white eggs are laid. 
In the work of excavation, which occupies some 
little time, the closed beak is the principal tool em- 
ployed, the feet being used merely for the purpose 
of removing the loosened soil, and not for actual 
digging operations. The hole, once made, is used 
again and again in succeeding years, the excavator 
