ough the smoke. It came in a lumbering gallop, a huge
and terribly frightened beast. It saw the fires in front of it.
Screaming it tried to turn back. The pressure of the horde behind
carried it along.

A confused mass of dark bodies poured into the city. There were hundreds
of them, thousands of them. Scared to the point of madness their one
thought was how to escape. The smallest of them weighed more than two
tons.

Craig, fighting against the effect of the gas, sobbed in sudden relief.

"Michaelson," he whispered. "You got there in time. You did it! You did
it--"

Phase four of the attack plan had come into operation. Phase four called
for Guru and the scientist to go around the edges of the vast swamp and
set it on fire. Part of the swamp foliage would not burn under any
circumstances. But great areas of dry reeds would burn like tinder.

The dinosaurs would run from the fires. The blazes would be set so the
great monsters would have to flee toward the city. At the proper moment,
the wall the Ogrum had built to keep them from the city would be blown
up.

The dinosaurs would stampede across the city.

Craig remembered reading of the stampede of the long-horn cattle in the
early days of the American west. Thousands of cattle, running madly,
shook the earth with the thunder of their hooves, destroyed everything
that stood in their way.

Not cattle, but dinosaurs, were stampeding across the city of the Ogrum.

Too late, the Ogrum saw them coming. They tried to run. The great beasts
trampled them into muck. Huts, struck by the maddened animals, flew to
pieces. Many of them, blinded, not knowing where they were going, ran
into the temple. The great building shuddered at each impact. Voronoff,
caught somewhere in that wild stampede, must have known too late that he
had deserted too soon, before he knew the complete plan of attack.
Either he did not know of phase four or the Ogrum had not believed him
when he told them about it.

[Illustration: The great beast trampled them into the muck]

For hours, it seemed to Craig, the screams of the Ogrum echoed through
the city. The screams were drowned in the earth-shaking thunder of the
stampede. The herd of dinosaurs crossed the city, turned and swept along
the edge of the bay. By the time the last of them had passed through,
the only building left standing in the whole area was the temple.
Everything else had been smashed flat. Smouldering fires were rising
again in