moved with her--a sphere through which no enemy could pass--a sphere
against the intangible surface of which even the most powerful engines
of the air dashed themselves in vain.

And still, as others and still others came charging up to the attack
like knights in joust, they fell. One by one the white wool cushions
of the cloud, gold-broidered by the magic needles of the sun, received
them. One by one they faded, vanished, were no more.

So, all disappeared. Between a hundred and a hundred and twenty-five
planes were silently, swiftly, resistlessly sent down in no more
than twenty minutes, while the watchers stood there in the gallery,
fascinated by the wondrous precision and power of this new and
far-outflung globe of protection.

And again the blood-red morning sky grew clear of attackers. Again,
between high heaven's black vault and the fantastic continent of cloud
below, nothing remained but free vacancy. The Master smiled.

"Vibrations, my dear Major!" said he. "Neutralize the currents
delivered by the magnetos of hostile planes to their spark-plugs, and
you transform the most powerful engines into inert matter. Not all the
finely adjusted mechanism in the world, nor the best of petrol, nor
yet the most perfect skill is worth _that_," with a snap of the strong
fingers, "when the spark dies.

"My device is the absolute ruler of whatever spark I direct it
against. Our own ignition is screened; but all others within the
critical radius become impotent. So you recognize, do you not, the
uselessness of machine-guns? The groundlessness of any fears about the