Analysis of Nocturnal Vigils

Why do you chide me that, when mortals yield
To slumber's charm, from sleep I ask no boon,
But from my casement watch the maimëd moon
Fainting behind her ineffectual shield:
Unto the chime by stately planets pealed
My song, my soul, my very self attune,
And nightly see, what none can see at noon,
The runic volume of the sky unsealed?
Haply the hour may come when grateful Night
Will these brief vigils endlessly repay,
And, on the dwindling of my earthly day,
Keep, like her stars, my heavenly fancies bright;
And glorious dreamings, shrouded now from sight,
Dawn out of darkness, not to sleep for aye.