that Arctic scene. Dave's hand trembled with excitement as he arranged
the two sacks beside the Doctor. Even the Doctor's hand shook as he
opened one sack and drew forth a number of small iron objects, the size
and shape of a bicycle handle-bar grip. His face grew stern.

"Understand Mill's grenades?" he asked.

"Yes."

"All right. When I say 'Go' drop ten of these as fast as you can release
the pins. Drop 'em on their shack."

Dave's heart thumped violently. He had thrown Mill's grenades at manikin
"enemies," but never had he hurled them where human flesh was the target.
Slowly, mechanically, he arranged the ten grenades in a row.

"Go!" The word sang in his ears.

Ten seconds later from below came two sharp reports--his grenade and the
Doctor's. They were off together. Crash followed crash in quick
succession until the row was finished. Silence followed for a single
second. Then came the cries and curses of men, as they staggered from
their half-demolished shelter and began to scatter. Dave's heart thumped.
There were fifteen, at least.

"Now!" exclaimed the Doctor, and lifting one of the large spheres he
dropped it over the ledge's edge. Just as that instance Dave saw one
of the rascals raise his rifle and fire. Immediately there came a cry
of distress. Dave thought he recognized the voice and a lump rose in
his throat.