Cancel, and tear to pieces, that great bond
Which keeps me pale! Light thickens; and the crow
Makes wing to the rooky wood;
Good things of day begin to droop and drowse;
While night’s black agents to their prey do rouse.
Lady Macbeth had already anticipated the spirit of this dread summons when, on the eve of Duncan’s coming to her castle, she cries out in the impatience of her passionate impulse:
Come, thick night,
And pall thee in the dunnest smoke of hell!
That my keen knife see not the wound it makes;
Nor heaven peep through the blanket of the dark,