“Wait,” said Brissac in a half-whisper.  In his second pantry rummaging he had found nothing more promising than a cast-iron skillet—­promising because it had weight and a handle to wield it by.  The intending incendiary was no more than a few yards from his goal when Brissac rose up opposite the nearest shattered window and hurled the skillet like a clumsy discus.  His aim was true to a hand’s-breadth:  a bullet from Adair’s pistol could have done no more.  With a cry that was fairly shogged out of him by the impact of the iron missile, the man flung away his burden, dropped in his tracks and lay groaning.

They looked for another storm of lead to follow this, and hugged the floor in readiness for it.  When it did not come, Ford crept to the hole in the car floor and listened long and intently.  Half an hour he had given Frisbie to get his track-layers together, and to cover the eight miles of rough-laid rails with the construction train.  What was delaying him?

“You said Gallagher ditched your car:  did it block the track?” he asked of Adair.

“It did, didn’t it, Brissac?” was the answer, and the assistant confirmed it.

“Then that is why Frisbie can’t get to us.  Was Gallagher’s engine still on the rails?”

“It was.”

Ford sat up and nursed his knees.  “Dick will make a way if he can’t find one ready made.  But it may take hours.  Meanwhile, if these devils have scouts out—­”

“Yes?” said Adair.

“They’ll bring the warning, and there won’t be much more time wasted in experiments.  They can do us up, if they get right down to business.”

“What are they doing now?” Adair asked of Brissac, who was on watch on the commissary side.

“I’ll be hanged if I know.  It looks like a young cannon, and it’s pointed this way.  By George! it’s coming—­coming by its all alone, too!”

By this time they were all watching the new menace.  Brissac’s description fitted it accurately; a cylindrical object mounted upon a pair of small wheels taken from the commissary store-room truck.  It came toward the Nadia by curious surges—­a rush forward and a pause—­trailing what appeared to be a long iron rod behind it.

Ford hit upon the explanation.  The cylindrical thing was another gas-pipe bomb; the iron tail was a smaller pipe containing and armoring the fuse, and serving also as the means of propulsion.  They were coupling on additional lengths of the fuse-carrying pipe as they were needed; hence the jerking advances and pauses.

Adair’s low laugh was as care-free as ever.

“A practical illustration of the tail wagging the dog,” he remarked.  “But the dog will wag us good and plenty when they get him where they want him.  You can’t fish that thing up through the hole with your wire—­or crop the tail.”

“No; it’s a run for it, this time,” said Ford, rising and stripping his coat.

But Brissac was pointing to three or four men dodging from shadow to shadow under the masthead lights and circling wide to tighten the line of circumvallation.