y of the Thrushes make use of large flat leaves, and
also of rags and pieces of paper. Robins stiffen their nests by making
in them a substantial cup of mud, which, when dry, adds greatly to the
solidity of the structure. On the island of Cape Hatteras there are
many sheep, and many Prairie Warblers of the region make their nests
entirely of wool.

The most dainty structure built, in this country, by the bill and feet
of birds, is the nest made by the Ruby-throated Hummingbird. When
completed it is scarcely larger than an English walnut, and is saddled
on a small horizontal limb of a tree, often many feet from the ground.
It is composed almost entirely of soft plant fibres, fragments of
spiders' webs sometimes being used to hold them in shape. The outer
sides are thickly studded with bits of lichen, and practised, indeed,
is the eye of the man or woman that can distinguish it from a knot on a
limb. Although the Hummingbird's nest is exceedingly frail, there is
nothing on record to show that {30} any great number of them come to
grief during the summer rains. It is, however, not called upon for a
long term of occupation. Within a month after the two white eggs are
laid the young depart on their tiny pinions. Young birds that require
a longer period for growth before leaving the nest are furnished
usually with more enduring abiding places. {31} In the case of the
Bald Eagle, the young of which do not fly until they are many weeks
old, a most substantial structure is provided.

[Illustration: Nest of the Ruby-throated Hummingbird]

It was on the twentieth of January, a number of years ago, that the
writer was first delighted by the sight of a Bald Eagle's nest. It was
in an enormous pine tree growing in a swamp in central Florida, and
being ambitious to examine its contents, I determined to climb to the
great eyrie in the topmost crotch of the tree, one hundred and
thirty-one feet above the earth. By means of climbing-irons and a rope
that passed around the tree and around my body, I slowly ascended,
nailing cleats for support as I advanced. After two hours of toil the
nest was reached, but another twenty minutes were required to tear
aside enough of the structure to permit climbing up one of the limbs on
which it rested. In doing this there were brought to view several
layers of decayed twigs, pine straw, and fish bones, showing that the
birds had been using the nest for many years. Season after season the