His laboratory, I may say, was at the very edge of the University buildings, with the campus back of it, but opening on the other side on a street that was ordinarily not overcrowded.

We got up as usual the next day and, quite early, went over to the laboratory.  Kennedy, as was his custom, plunged straightway into his work and appeared absorbed by it, while I wrote.

“There is something queer going on, Walter,” he remarked.  “This thing registers some kind of wireless rays—­infra-red, I think,—­ something like those that they say that Italian scientist, Ulivi, claims he has discovered and called the ‘F-rays.’”

“How do you know?” I asked, looking up from my work.  “What’s that instrument you are using?”

“A bolometer, invented by the late Professor Langley,” he replied, his attention riveted on it.

Some time previously, Kennedy had had installed on the window ledge one of those mirror-like arrangements, known as a “busybody,” which show those in a room what is going on on the street.

As I moved over to look at the bolometer, I happened to glance into the busybody and saw that a crowd was rapidly collecting on the sidewalk.

“Look, Craig!” I called hastily.

He hurried over to me and looked.  We could both see in the busybody mirror a group of excited passersby bending over a man lying prostrate on the sidewalk.

He had evidently been standing on the curbstone outside the laboratory and had suddenly put his hand to his forehead.  Then he had literally crumpled up into a heap, as he sank to the ground.

The excited crowd lifted him up and bore him away, and I turned in surprise to Craig.  He was looking at his watch.

It was now only a few moments past nine o’clock!

Not quarter of an hour later, our door was excitedly flung open and Elaine and Perry Bennett arrived.

“I’ve just heard of the accident,” she cried, fearfully.  “Isn’t it terrible.  What had we better do?”

For a few moments no one said a word.  Then Kennedy began carefully examining the bolometer and some other recording instruments he had, while the rest of us watched, fascinated.

Somehow that “busybody” seemed to attract me.  I could not resist looking into it from time to time as Kennedy worked.

I was scarcely able to control my excitement when, again, I saw the same scene enacted on the sidewalk before the laboratory.  Hurriedly I looked at my watch.  It was ten o’clock!

“Craig!” I cried.  “Another!”

Instantly he was at my side, gazing eagerly.  There was a second innocent pedestrian lying on the sidewalk while a crowd, almost panic-stricken, gathered about him.

We watched, almost stunned by the suddenness of the thing, until finally, without a word, Kennedy turned away, his face set in tense lines.

“It’s no use,” he muttered, as we gathered about him.  “We’re beaten.  I can’t stand this sort of thing.  I will leave to-morrow for South America.”