suppose every reader is disgusted at the tautology in this passage,
_Time and the hour_, and will therefore willingly believe that
Shakespeare wrote it thus,

_Come what come may_,
Time! on!--_the hour runs thro' the roughest day_.

Macbeth is deliberating upon the events which are to befall him, but
finding no satisfaction from his own thoughts, he grows impatient of
reflection, and resolves to wait the close without harrassing hinaelf
with conjectures.

_Come what come may_.

But to shorten the pain of suspense, he calls upon Time In the usual
stile of ardent desire, to quicken his motion,

_Time! on!_ --

He then comforts himself with the reflection that all his perplexity
must have an end,

--_the hour runs thro' the roughest day._

This conjecture is supported by the passage in the letter to his lady,
in which he says, _they referred me to the_ coming on of time, _with
Hail, King that shalt be_.

I.iii.149 (416,1) My dull brain was wrought] My head was _worked_,
_agitated_, put into commotion.