[ 26 o ] 
permanent ; with this difference, that whereas the fliell 
of the martin is nearly hemifpheric, that of the fwallow 
is^ open at the top, and like half a deep difli. This neft is 
lined with fine gralfes and feathers, which are often col- 
ledted as they float "in the air. Wonderful is the ad- 
drefs which this adroit bird fhews all day long in afeend- 
ing and defeending, with fecurity^ through fo narrow a 
pafs. When hovering over the mouth of the funnel, 
the vibrations of her wings, adling on the confined air, 
occafion a rumbling like thunder. It is not improbable, 
that the dam fubmits to this inconvenient fltuation lb 
low in the fhaft, in order to fecure her broods from ra- 
pacious birds, and particularly from owls, which fre- 
quently fall down chimnies, perhaps in attempting to 
get at thefe neftlings. The fwallow lays from four 
to fix white eggs, dotted with red fpecks ; and brings out 
her firfl: brood about the lafl week in June, or the firfl 
week in July. The progreflive method by which the 
young are introduced into life is veryamufing. Firfl: they 
emerge from the fliaft with difficulty enough, and often 
fall down into the rooms below. For a day or fo they 
are fed on the chimney-top ; and then are condudled to 
the dead leaflefs bough of fome tree, where, fitting in a 
row, they are attended with great afliduity, and may then 
be called perchers. In a day or two more they become 
flyers^ but are flill unable to take their own food; there- 
fore they play about near the place where the dams are 
hawking for flies; and when a mouthful is collected, at 
a certain lignal given, the dam and the neftling advance 
rifing 
