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NOTES.
number of these birds return every year to build in the places they frequented before; and that each pair set immediately about repairing a particular nest.
"You hide, tho' none know where or how,
In the cliff's excavated brow," &c.
Many persons have supported the idea, that the Hirundines linger concealed among rocks and hollows in a torpid state, and that all do not emigrate.
"Or if, by instinct taught to know
Approaching dearth of insect food,
To isles and willowy aits you go."
Another opinion is, that the Swallows, at the time they disappear, assemble about rivers and ponds, and
