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 silvery mist.
In another moment Alice was through the glass, and had jumped lightly down into the Looking-glass room.

The very first thing she did was to look whether there was a fire in the fireplace, and she was quite pleased to find that there was a real one, blazing away as brightly as the one she had left behind.

"So I shall be as warm here as I was in the old room," thought Alice: "warmer, in fact, because there'll be no one here to scold me away from the fire.

Oh, what fun it'll be, when they see me through the glass in here, and can't get at me!" Then she began looking about, and noticed that what could be seen from the old room was quite common and uninteresting, but that all the rest was as different as possible.