abled them to time their voices, and to swell or
diminish the volume of sound. Some of this effect is undoubtedly
produced by the gradual manner in which the different voices join in
harmony, beginning with one or two, and increasing in numbers in a sort
of geometrical progression, until all are singing at once, and then in
the same gradual manner becoming silent. This produces the effect of a
perfect _crescendo_ and _diminuendo_. Beginning, as it seems, at a
distance, one voice leads on another, and the numbers multiply until
they make a loud shout, which dies away gradually until one single
voice winds up the chorus. These concerts are repeated at intervals,
sometimes for an hour in duration.

Another peculiar habit of the Hemp-bird is that of building a nest, and
then tearing it to pieces before any eggs have been deposited in it,
and using the materials to make a new nest in another locality. In
former years I have repeatedly watched this singular operation, in the
Lombardy poplars that stood before my study-windows. I have thought
that the male bird only was addicted to this practice, and that this
might be his method of amusement while unprovided with a partner. The
nest of the Hemp-bird is made of cotton, the down of the fern, and
other soft materials, woven together with threads and the fibres of
bark, and lined with thistle-down, if it be late enough to obtain it,
and sometimes with cow's hair. It is commonly placed in the fork of the
slender branches of a maple, linden, or poplar, and is fastened to them
with singular ingenuity.

Among the earliest songsters of spring, occasionally tuning his voice
before the arrival of the multitudinous choir, is the Crimson Finch or
American Linnet (_Fringilla purpurea_). I have frequently heard his
notes on warm days in March, and once, in a very mild season, I heard
one warbling cheerily on the 18th of February. But the Linnet does not
persevere like the Song-Sparrow, after he has once commenced. His voice
is only occasionally heard, until the middle of April, after which he
is a very constant singer.

The notes of this bird are very simple and melodious, and some
individuals greatly excel others in their powers of song. It is
generally believed that the young males are the best singers, and that
age diminishes their vocal capacity. The greater number utter only a
few strains, resembling the notes of the Warbling Fly-catcher, (_Vireo
gilvus_,) and these are constantly r