Capt. CARMICHAEL, an intelligent and active observer, mentions the
following fact respecting the natural history of the swallow: -

       Swallows are birds of passage at the southern extremity of Africa as
well as in Europe, they return to the Cape of Good Hope in September, and quit
it again in March and April.

       Capt. CARMICHAEL happening to be stationed some time at the Eastern
extremity of the colony, a pair of these birds (hirundo capensis) soon after
their arrival built their nest on the outside of his house, the whole of it was
covered in, and it was furnished with a long neck or passage through which the
birds entered and cam out; it resembled the longitudinal section of a Florence
oil flask. This nest having fallen down after the young birds quitted it; the
same pair, as he disposed to believe, built again on the old foundation in
the month of February following , but he remarked on this occasion an
inprovement in the construction of it which can hardly be referred to the dictates of
mere instinct.

       In building the first the birds were satisfied with a single opening,
but this one was furnished with one on each side, and on watching their
motions he observed they invariably entered at one and came out on the other.

       One object obtained by this improvement was saving themselves the
trouble of turning in the nest, but the chief object appeared to be to facilitate
their escape from the attacks of serpents which harbour in the roofs or crawl
up along the walls, and not unfrequently devour both the mother and her young.



       On the river Mississippi and its tributary streams, there are no less
than 35 boats on this construction plying constantly, admeasuring 7259 tons;
and 30 new ones building, admeasuring 5995 tons.