s going to make interplanetary history. It's the biggest
thing since the discovery of the first dead city on Mars. We've got to
go back to the ship and bring the others. They've got to see this. But,
Brad, before they do, I'm going in there. I want to be the first to see
what these people looked like. There must be a door somewhere--"

And before Nellon could voice the protest which rose to his lips, Big
Tim had started away on an eager circuit of the green wall. Nellon stood
looking after him in indecision, torn between conflicting impulses. Then
he tightened his lips and followed in the direction which Big Tim had
taken. But before Nellon could reach him, the other's excited voice
crashed in his earphones.

"I've found it, Brad! There _is_ a door here."

Nellon jerked into a run. He found Big Tim standing upon a short ramp
before a section of the wall which was different from the rest. It was a
dark area, rectangular in shape. At one side, seen dimly through the
strange green substance, was an arrangement of rods and gears which was
obviously an operating mechanism. Protruding from a slot in the wall,
and clearly connected with the mechanism, was a short lever.

Big Tim's blue eyes glittered with daring. His tow hair awry, he looked
more than ever the picture of an overgrown, impulsive boy.

"Good heavens, guy, you surely don't intend to go in there!" Nellon
exclaimed. "We don't know what sort of--"

Big Tim gave a short, excited laugh. "Look--there's nothing to be afraid
of. There's just that green light up there and the people, and they are
dead. Everything in this place is dead. Brad, this is the chance of a
lifetime. We'll be the first to look upon the faces of an
extra-terrestrial race since the Martians."

Big Tim pulled the opening lever. There was a moment of appalled and
complete quiet. Then hidden motors hummed into alien life, and slowly
the door before them slid aside. Undimmed now by its confining walls,
the green radiance poured through the opening in a blinding flood.

"Come on," Big Tim urged. And without any hesitation on his own part, he
stepped through, to be bathed instantly in the emerald glow.

* * * * *

Nellon moved to the open doorway. The emerald rays from the globe fell
upon him with an almost sensible warmth. Again that weird peace and
comfort was upon him, but more overpoweringly now. He felt a rising tide
of drowsiness. In some strange way, he knew