ardly had he gone a dozen steps when he suddenly understood the meaning of the high-walled enclosure to his right!

Off in a far corner rose a slate colored mound that at first glance he had taken for a great heap of inanimate dirt. The mound began to move toward him—and metamorphosed into an animal, a thing that made Brand blink his eyes to see if he were dreaming, and then stop, appalled, to look at it.

He saw a body that dwarfed the high retaining walls to comparative insignificance. It had a tree-like tail that dragged behind it; and a thirty-foot, serpentine neck at the end of which was a head like a sugar barrel that split into cavernous jaws lined with backward-pointing teeth. Two eyes were set wide apart in the enormous head, eyes that were dead and cold and dull, yet glinting with senseless ferocity. It was the sort of thing one sees in delirium.

With increasing energy the creature made for him, till finally it was approaching his sector of the wall at a lumbering run that was rapid for all its ungainliness.

It was apparent at a glance that the snaky neck, perched atop the lofty shoulder structure, would raise the head with its gaping jaws to his level on the wall! Brand ran. And after him thudded the gigantic lizard, its neck arching up and along the wall to reach him.

A scant five yards ahead of the snapping jaws, Brand reached his goal, the dome, and clambered over its curved, metal roof away from the monster's maw.

He stopped to pant for breath and wipe the sweat from his streaming face. "Thank God it didn't get me," he breathed, looking back at the bellowing terror that had pursued him. "Wonder why it's there? It's too ferocious to be tamed and used in any way: it must be kept as a threat to hold the slaves in hand. It certainly looks well fed...."

He shuddered; then he began to explore the dome of the building for a means of entrance.