The song of the nightingale, in praise of which volumes have been written, is perhaps more beautiful than that of any other bird, though I have heard wonderful efforts from the mocking-bird in the United States and from the bulbuls along the banks of the Jordan. The latter are sometimes, more especially in poetry, regarded as identical with the nightingale; and, indeed, some ornithologists hold the two to be closely related. What a gap there is between the sobbing cadences of the nightingale and the rasping note of the nightjar, which, with specific reference to a Colonial cousin of that bird Tasmanians ingeniously render as "more pork"! It seems almost ludicrous to include under the head of birdsong not only the music of the nightingale, but also the croak of the raven and the booming note of the ostrich. Yet these also are the love-songs of their kind, and the hen ostrich doubtless finds more music in the thunderous note of her lord than in the faint melody of such song-birds as her native Africa provides. The nightingale sings to his mate while she is sitting on her olive-green eggs perching on a low branch of the tree, at foot of which the slender nest is hidden in the undergrowth. So much is known to every schoolboy who is too often guided by the sound on his errand of plunder; and why the song of this particular warbler should have been described by so many writers as one of sadness, seeing that it is associated with the most joyous days in the bird's year, passes comprehension. So obviously is its object to hearten the female in her long and patient vigil that as soon as the young are hatched the male's voice breaks like that of other choristers to a guttural croak. It is said, indeed--though so cruel an experiment would not appeal to many--that if the nest be destroyed just as the young are hatched the bird recovers all his sweetness of voice and sings anew while another home is built.