and he gathered his muscles to
spring at the hateful figures. But he could not move. At waist and
throat, at wrists and ankles, were hoops of metal. He closed his eyes
again while the burning waves of invisible fire shot through him
recurrently from head to foot.

Dully he wondered that he was still alive. His last recollection had
been of the Rogan leader pointing his shock-tube full at him, his
shapeless countenance working with murderous fury. However, alive he
was; and most unenviably so!

His hands, circumscribed to a few inches of movement by the bonds on
his wrists, felt the smooth substance at his back. And with a thrill
of horror he realized his position: he was crucified against the metal
slab on which the slave had writhed in agony a short half hour ago.

Again he strained and tugged, vainly, to get free. Off to one side,
pressed back against a huge glass experimental tank, he saw the
beautiful Greca, her eyes wide with horror; and caught her frantic
pleading message to her "Great White One."

* * * * *

The Rogan leader, squealing and grimacing, advanced toward the victim
on the metal plate. One of the long arms went out and a sucker-disk
was pressed to Dex's cheek. Dex quivered at the loathsome contact of
that soft and slimy substance; then set his jaws to keep from groaning
as the disk was jerked away, to carry with it a fragment of skin and
flesh.

Gingerly, the tall leader felt the twitching, blackened stump of his
blasted arm. Dex grinned mirthlessly at that: he'd struck one or two
blows in his own defense, anyhow!

At sight of the Earthman's grin, an expression of defiance and grim
joy that needed no interpreting to be understandable, the Rogan leader
fairly danced with rage. His long arm went out to the switch beside
the plate, and pulled it down another notch--just a little, not nearly
to the current that had torn at the slave.

At the increased torment resulting from that slight movement of the
regulating lever, Dex yelled aloud in spite of all his will power. It
seemed as though his whole body were about to burst into
self-generated flame. Every cell and fiber of him seemed on the verge
of flying apart. He could feel his eyes start from his head, could
feel every hair on his scalp stand up as though discharging electric
sparks.

A minute or two of that and he would go mad! He cried out again, and
twisted helplessly in his bonds. And then the terrible tortu