As we drew near the great gates swung back upon their hinges.

We passed them--with what sensations I cannot describe--and groped our way down a short corridor which ended in tall, iron-covered doors.

These also rolled open at our approach, and next instant we staggered back amazed and half-blinded by the intense blaze of light within.
Imagine, you who read, the nave of the vastest cathedral with which you are acquainted.

Then double or treble its size, and you will have some conception of that temple in which we found ourselves.

Perhaps in the beginning it had been a cave, who can say?
but now its sheer walls, its multitudinous columns springing to the arched roof far above us, had all been worked on and fashioned by the labour of men long dead; doubtless the old fire-worshippers of thousands of years ago.
You will wonder how so great a place was lighted, but I think that never would you guess.