The great Magician Merlin had devised,
By his deep science, and hell-dreaded might,
A looking-glass, right wondrously built.
This mirror showed in perfect sight,
Whatever thing was in the world,
That the looker hoped to find;
Whatever foe had done, or friend or fiend,
Was thus discovered therein.

 
This mirror . . .
Has power such that men may in it see
Whether will come any adversity
Unto your realm, or yourself also;
And reveal who is your friend or foe.
And also this: if any lady bright
Has her heart set on any shining knight
If he is false, she shall his treason see.
And his other love, and all his secrecy.

 
“Now, if you’ll only wait, Kitty, and not talk so much, I’ll tell you all my ideas about Looking-glass House. First, there’s the room you can see through the glass—that’s just the same as our drawing room, only the things go the other way . . . Let’s pretend there’s a way of getting through into it, somehow, Kitty. Let’s pretend the 
 
 
glass has got all soft like gauze, so that we can get through. Why, it’s turning into a sort of mist now, I declare! It’ll be easy enough to get through—” She was up on the chimney-piece while she said this, though she hardly knew how she had got there. And certainly the glass was beginning to melt away, just like a bright mist.

Vulcan, the Roman god of fire and metalwork, was said to have a magic mirror that showed him scenes from the past, present, and future.