He did not answer. He sent a questioning look toward Drorathusa and her companions. Mine followed. The faces of the Dromans seemed to glimmer ghostlike in the thickening, awful darkness. Upon those pale features, however, was no discoverable sign of alarm, of uneasiness even.

The gloom deepened about us. Pitchy darkness came down with a rush. Far away, and up along the roof, there were pale flickerings and flashes. Then the light burst out, so sudden and so strong that pain shot through the eyes.

Came a cry, and I turned to see Drorathusa pointing, pointing down toward those cycads.

"There it is, Bill!" exclaimed Milton. "There it is again! See it moving?"

I saw it, but it was for a fleeting moment only. And, I thought, I saw something else.

"A little nearer this time," Rhodes told me. "There can be no doubt that it is watching us."

"Evidently," I said, "it is moving over to lie in wait for us. And, unless I'm very much deceived, it isn't alone."

"Hum," said Rhodes. "Queer place, Bill, to go into. Even our Hypogeans, it seems, don't know what to make of that apparition."

They were conversing in low tones, casting searching, apprehensive looks along the ragged margin of the forest.

The gloom was falling again. Denser and denser it grew about us. Fainter, more and more dreadful became those distant flickerings and flashes along the great vaulted roof. Darkness, blackness was involving everything. Dimmer still became the flickerings. The stillness was utter, portentous. There was not the gentlest movement of air. The light gave a last faint, angry gleam and went out altogether.