"You look and talk like an honorable man," said Kandus; "and, while I don't understand, I am inclined to believe; however, you'd better pick out some place on Barsoom as your home when anyone else in Invak questions you; and you may soon be questioned—here we are at the gates of the city now."

Chapter 3

Invak! The city in the Forest of Lost Men. At first only a gate was visible, so thickly set were the trees that hid the city wall—the trees and the vines that covered the wall.

I heard a voice challenge as we approached the gate, and I heard Pnoxus' voice reply, "It is Pnoxus, the prince, with twenty warriors and a prisoner."

"Let one advance and give the countersign," said the voice.

I was astonished that the guard at the gate couldn't recognize the jeddak's son, nor any of the twenty warriors with him. I suppose that one of the voices advanced and whispered the countersign, for presently a voice said, "Enter, Pnoxus, with your twenty warriors and your prisoner."

Immediately the gates swung open, and beyond I saw a lighted corridor and people moving about within it; then my rope tightened and I moved forward toward the gate; and ahead of me, one by one, armed men suddenly appeared just beyond the threshold of the gateway; one after another they appeared as though materialized from thin air and continued on along the lighted corridor. I approached the gate apparently alone, but as I stepped across the threshold there was a warrior at my side where the voice of Kandus had walked.

I looked at the warrior, and my evident amazement must have been written large upon my face, for the warrior grinned. I glanced behind me and saw warrior after warrior materialize into a flesh and blood man the moment that he crossed the threshold. I had walked through the forest accompanied only by voices, but now ten warriors walked ahead of me and nine behind and one at my side.

"Are you Kandus?" I asked this one.

"Certainly," he said.

"How do you do it?" I exclaimed.

"It is very simple, but it is the secret of the Invaks," he replied. "I may tell you, however, that we are invisible in daylight, or rather when we are not illuminated by these special lamps which light our city. If you will notice the construction of the city as we proceed, you will see that we take full advantage of our only opportunity for visibility."

"Why should you care whether other people can see you or not?" I asked. "Is it not sufficient that you can see them and yourselves?"

"Unfortunately, there is the hitch," he said. "We can see you, but we can't see each other any more than you can see us."