May: which consists, like that of
the house-martin, of a crust or shell composed of dirt or mud, mixt
with short pieces of straw to render it tough and permanent; with this
difference, that whereas the shell of the martin is nearly
hemispheric, that of the swallow is open at the top, and like half a
deep ditch; this nest is lined with fine grasses, and feathers which
are often collected as they float in the air.

Wonderful is the address which this adroit bird shows all day long, in
ascending and descending with security through so narrow a pass. When
hovering over the mouth of the funnel, the vibration of her wings,
acting on the confined air, occasions a rumbling like thunder. It is
not improbable that the dam submits to this inconvenient situation so
low in the shaft, in order to secure her broods from rapacious birds;
and particularly from owls, which frequently fall down chimneys,
perhaps in attempting to get at these nestlings.

The swallow lays from four to six white eggs, dotted with red specks;
and brings out her first brood about the last week in June, or the
first week in July. The progressive method by which the young are
introduced into life is very amusing: first they emerge from the shaft
with difficulty enough, and often fall down into the rooms below; for
a day or so they are fed on the chimney-top, and then are conducted to
the dead leafless bough of some tree, where, sitting in a row, they
are attended with great assiduity, and may then be called perchers. In
a day or two more they become fliers, but are still unable to take
their own food; therefore they play about near the place where the
dams are hawking for flies: and when a mouthful is collected, at a
certain signal given, the dam and the nestling advance, rising toward
each other, and meeting at an angle; the young one all the while
uttering such a little quick note of gratitude and complacency, that a
person must have paid very little regard for the wonders of nature
that has not often remarked this feat.

The dam betakes herself immediately to the business of a second brood
as soon as she is disengaged from her first, which at once associates
with the first broods of house-martins, and with them congregates,
clustering on sunny roofs, towers and trees. This _hirundo_ brings out
her second brood toward the middle and end of August.

All summer long, the swallow is a most instructive pattern of
unwearied industry and affection: for from morn