"Try one," said he.
"I get him," reported Simmons, after a moment.
"Send him anything plausible and reassuring," commanded Eldridge hastily. He turned to his small and attentive audience in triumph. "Thus, gentlemen," he announced, "we have proven conclusively that our man is located between forty and fifty miles from New York. If we draw two circles, with this building as center, the circumference of one of which is fifty, the other forty miles away, we define the territory within which the malefactor in question is to be found."
The people in the room crowded close about the table to examine the map upon which Professor Eldridge had drawn the circles.
"There's an awful lot of country—some of it pretty wild," objected the Bulletin man. "It will be a long job to hunt a man down in that territory."
"Even if it were as extensive a task as a hasty review of the facts might indicate," stated Eldridge, "I venture to assert that enough men would be forthcoming to expedite such a search. But modifying circumstances will lighten the task."
"How's that?" asked the Banner man, speaking for the others' evident interest.
"We have no means of surmising the method by which this man succeeds in arresting vibratory motions of certain wave-lengths," said Eldridge didactically, "any more than we are able to define the precise nature of electricity. But, as in the case of electricity, we can observe the action of its phenomena. Two salient features leap out at us: one is that these phenomena are limited in time; the other that they are limited in space. The latter aspect we will examine, if you please, gentlemen.
"The phenomena have been directed with great accuracy (a) at the Atlas Building; (b) at this city and some of its immediate suburbs. The peculiarity of this can not but strike an observant mind. How is this man able, at forty or fifty miles distance, to concentrate his efforts on one comparatively small objective? We can only surmise some system of insulating screens or focal mirrors. I might remark in passing that the existence of this power to direct or focus the more rapid ethereal vibrations would be a discovery of considerable scientific moment. But if this is the method employed, why do we not cut a band of vibratory nullifications, rather than touch upon a focal point?"
"Repeat softly," murmured the irrepressible Register man.