Oi' SELBORNE. 
181 
LETTER XVI. 
TO THE HONOURABLE DAINES BARRINGTON. 
Selborne, Nov. 20, 1773. 
N obedience to your inj unctions I sit down to 
give you some account of the house martin 
or martlet; and, if my monography of this 
little domestic and familiar bird should happen 
to meet with your approbation, I may pro- 
bably soon extend my inquiries to the rest of the British 
Hirundines — the swallow, the swift, and the bank martin. 
A few house martins begin to appear about the 16th of 
April ; usually some few days later than the swallow. For 
some time after they appear, the Hirundines in general pay 
no attention to the business of nidification, but play and 
sport about either to recruit from the fatigue of their 
journey, if they do migrate at all, or else that their blood 
may recover its true tone and texture after it has been so 
long benumbed by the severities of winter. About the 
middle of May, if the weather be fine, the martin begins to 
think in earnest of providing a mansion for its family. The 
crust or shell of this nest seems to be formed of such dirt or 
loam as comes most readily to hand, and is tempered and 
wrought together with little bits of broken straws to render 
it tough and tenacious. As this bird often builds against 
a perpendicular wall without any projecting ledge under, it 
requires its utmost efforts to got the first foundation firmly 
fixed, so that it may safely carry the superstructure. On 
this occasion the bird not only clings with its claws, but 
partly supports itself by strongly inclining its tail against 
the wall, making that a fulcrum; and thus steadied, it 
works and plasters the materials into the face of the brick 
or stone. But then, that this work may not, while it is 
soft and green, pull itself down by its own weight, the pro- 
