HOUSE-MARTIN. 
153 
of this little domestic and familiar bird should happen to meet 
with your approbation, I may probably soon extend my enquiries 
to the rest of the British hirundines — the swallow, the swift, and 
the bank-martin. 
A few house-martins begin to appear about the sixteenth 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 line, 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 ^d 
wrought together with little bits of broken straws, to render it 
tough and tenacious. As this bird often builds against a per- 
pendicular wall without any projecting ledge under, it requires 
its utm^ost efforts to get 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 ful- 
crum ; 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 provident architect has prudence and forbearance enough 
not to advance her work too fast ; but by building only in the 
morning, and by dedicating the rest of the day to food and 
amusement, gives it sufl&cient time to dry*and harden. About 
half an inch seems to be a sufi^icient layer for a day. Thus careful 
workmen when they build mud-walls (informed at first perhaps 
by this little bird) raise but a moderate layer at a time, and then 
desist ; lest the work should become top-heavy, and so be ruined 
by its own weight. By this method in about ten or twelve days 
is formed an hemispheric nest with a small aperture towards the 
top, strong, compact, and warm ; and perfectly fitted for all the 
purposes for which it was intended. But then nothing is more 
common than for the house-sparrow, as soon as the shell is 
finished, to seize on it as its own, to eject the owner, and to 
line it after its own manner.* 
• Upon which occurrence, instances have been known, and attested on the most unexception* 
