The second rule is that its song must be clear and swift. It is obvious at once that the emotion is homesickness. But what makes the lyric so different from this commonplace summary, what makes it so rich and memorable, is the haunting music which expresses the mood. We do not have to know where it is or anything about it to understand its power of enchantment. Nothing here can disturb the heart.
Evening brings the late birds home.
Magic has been created by the union of personal feeling and musical form. See the following poems full of singing words. Too Short .