I picked up my instruments and the medical kit; Larry and Olaf shouldered each a short ladder that was part of my equipment, and, with our electric flashes pointing the way, walked up the great stairs, through the enclosures, and straight to the grey stone.
By this time the moon had risen and its clipped light shone full upon the slab.

I saw faint gleams pass over it as of fleeting phosphorescence--but so faint were they that I could not be sure of the truth of my observation.
We set the ladders in place.

Olaf I assigned to stand before the door and watch for the first signs of its opening--if open it should.

The Becquerels were set within three-inch tripods, whose feet I had equipped with vacuum rings to enable them to hold fast to the rock.
I scaled one ladder and fastened a condenser over the boss; descended; sent Larry up to watch it, and, ascending the second ladder, rapidly fixed the other in its place.

Then, with O'Keefe watchful on his perch, I on mine, and Olaf's eyes fixed upon the moon door, we began our vigil.