"Why," explained Eldridge patiently, "are not the people and buildings between here and the unknown operator affected? The only hypothesis we are justified in working upon is that the man's apparatus is at a height sufficient to carry over intervening obstacles. This hypothesis is strengthened by the collateral fact that the territory we have just determined as that within which he must be found lies in the highlands of our own and neighboring states. We may, therefore, eliminate the low-lying districts within our radius."
Percy Darrow opened one eye.
"Perhaps he's up in a balloon," he drawled languidly; "better take along an aeroplane."
Eldridge cast on him a look of cold scorn. Darrow closed the eye.
CHAPTER XVII
DRAWING THE NET
The "zone of danger", as the Bulletin named it, was immediately the scene of swarming activities. Besides the expedition immediately despatched by the interests backing the investigation, several enterprising newspapers saw a fine chance for a big scoop, and sent out much-heralded parties of their own. The activities of these were well reported, you may be sure. Public interest was at once focused reassuringly on the chances of finding the annoying malefactor to-day or to-morrow; there no longer existed a doubt that he would be found. The weight of dread was lifted, and in the reaction people made light of the inconveniences and fun of the menacing messages that now came in by the dozen.
[Illustration: "Let Eldridge do his best.">[
It was necessary to take extraordinary precautions against thieves and fire; the people took them. It was needful to slacken business in order that the congestion of the rush hour might not again prove tragic; business was slackened. People were willing to undergo many things, because, after all, they were but temporary. The madman of the Catskills would sooner or later be found; his pernicious activities brought to a conclusion. The country to be searched was tremendous, of course, but the search was thorough.
The public delivered itself joyously to a debauch of rumors and of "extras". The insistent alarms of danger, trickling in slowly from the outside world, dried up in the warmth of optimism. Only the more thoughtful, to a few of whom these warnings came, coupled them with Monsieur X's repeated threats, and walked uncertain and in humility.