This was printed as a poem, not a song, in Godey's Lady's Book, Volume 24 (Philadelphia: Louis A. Godey, January, 1842), page 23:


IT IS THE TWILIGHT HOUR
By Epes Sargent.

It is the twilight hour,
    Leonore!
Along the western sky,
The clouds of sunset lie,
And I hear the pine-grove sigh,
    Leonore!

The purple eve is come,
    Leonore!
The last blush of the day
From the lake has fled away,
And the mountain-tops are gray,
    Leonore!

Oh! leave thy household task,
    Leonore!
Come where the woodbine twines
Its odour-breathing vines;
The star of evening shines,
    Leonore!

The song-birds are all mute,
    Leonore!
But dearer far to me,
Than note of bird can be,
Is a song of love from thee,
    Leonore!