'That's our pitch-pipe,' said Arnott. 'We may be a bit ragged. I've never conducted two hundred and fifty performers before.' He pulled out the couplers, and struck a full chord on the Service Communicators.
The beams of light leaped down again, and danced, solemnly and awfully, a stilt-dance, sweeping thirty or forty miles left and right at each stiff-legged kick, while the darkness delivered itself—there is no scale to measure against that utterance—of the tune to which they kept time. Certain notes—one learnt to expect them with terror—cut through one's marrow, but, after three minutes, thought and emotion passed in indescribable agony.
We saw, we heard, but I think we were in some sort swooning. The two hundred and fifty beams shifted, re-formed, straddled and split, narrowed, widened, rippled in ribbons, broke into a thousand white-hot parallel lines, melted and revolved in interwoven rings like old-fashioned engine-turning, flung up to the zenith, made as if to descend and renew the torment, halted at the last instant, twizzled insanely round the horizon, and vanished, to bring back for the hundredth time darkness more shattering than their instantly renewed light over all Illinois. Then the tune and lights ceased together, and we heard one single devastating wail that shook all the horizon as a rubbed wet finger shakes the rim of a bowl.
'Ah, that is my new siren,' said Pirolo. 'You can break an iceberg in half, if you find the proper pitch. They will whistle by squadrons
