Like vibrations of a bell,
And fashionable madmen raise
Their pedantic boring cry:
Every farthing of the cost,
All the dreaded cards foretell,
Shall be paid, but from this night
Not a whisper, not a thought,
Not a kiss nor look be lost.
Beauty, midnight, vision dies:
Let the winds of dawn that blow
Softly round your dreaming head
Such a day of welcome show
Eye and knocking heart may bless,
Find the mortal world enough;
Noons of dryness find you fed
By the involuntary powers,
By virtue of being alive the speaker will be able to bless the winds of dawn, as he comes through his night of sleep and is reborn into the new day. 
 The ‘knocking’ heart is an imaginative description, with its hint of danger and fear. It suggests time intruding or ‘knocking’.
Lullaby