signal rocket

Then a signal rocket, hissing into the quenching rain, told him of his fellow's distress.

He had a small signal-rocket mounted on the far side of that crater,—twenty-some miles.

The signal-rocket, traveling normally, might have attained a maximum velocity of some two thousand feet per second.

Once to the laboratory to talk, once to test a signal-rocket across the crater, and once when the distress-torp went off.

As the troops started out at night, for their assault, a signal rocket went up from Washington.