ACT 1, SCENE 4. The platform.
Enter HAMLET, HORATIO, and MARCELLUS

HAMLET
The air bites shrewdly; it is very cold.

HORATIO
It is a nipping and an eager air.

HAMLET
What hour now?

HORATIO
I think it lacks of twelve.

HAMLET
No, it is struck.

HORATIO
Indeed? I heard it not: then it draws near the season
Wherein the spirit held his wont to walk.

A flourish of trumpets, and ordnance shot off, within

What does this mean, my lord?