ly passed," said Migul. We stopped, I close beside the
stooping metal figure. The Robot's voice was a furtive sepulchral
whisper that filled me with awe.

"How long ago?" I asked.

"He passed here an hour or two ago, perhaps. The vibrations are fading
out. But it was Tugh. Well do I know him. Put your hand down. Feel the
vibrations?"

"I cannot. My fingers are not that sensitive, Migul."

A faint contempt was in the Robot's tone. "I forgot that you are a
man." Then it straightened, and the extended filaments slid back into
its fingers. It said softly, "There is one guard in this passage."

My heart leaped. "A human or a Robot?"

"A man. His name is Alent. He is at a gate that is too well fortified
for any Robot to assail, but he will pass humans. It will be necessary
for you to kill him."

* * * * *

I had no intention of doing that, but I did not say so. As we crept
forward to where I saw that the tunnel made a bend, with the fortified
gate just beyond it, there was in my mind that now I would do my best
to separate from Migul, using this guard as my pretext, for he would
doubtless pass me, but not the Robot. The palace was occupied, I
assumed, by friendly humans. I could get them to locate Tina and
Larry.... Then the flaws of this plan made themselves all too evident.
Larry might be with Tugh, and without Migul I could not follow Tugh's
trail. Worse than that, if I tricked Migul, the angered Robot would at
once return to Mary. I shuddered at the thought. That would not do. I
must try to get Migul past the guard.

I whispered, "When we reach the gate you stay behind me. Let me
persuade the guard."

"You will kill him? You have the weapon. He is fortified against the
Robot weapons, but yours will be strange to him."

"We will see."

We crept around the bend. A hundred feet further on I saw that the
passage was barred by a grille, faintly luminous with electrification.

I called cautiously:

"Alent! Alent!"

A glow of light illuminated me as I stood in the middle of the
passage; Migul was in a shadow behind me.

A man's voice answered, "You are a human? How come you there? Who are
you?"

"A stranger. A friend of the Princess Tina. I came in the
Time-traveling cage. I want to pass now into the palace."

* * * * *

I could see the dark man's figure behind the grille. His voice called,
"Come slowly forward and stop at twenty feet. Walk o