But, as usual, Craig was not without some resource, though it looked impossible to me to do anything but make a hit or miss arrest at the boat.  It was late in the evening when he returned from a conference with an officer of the Telegraph and Telephone Company to whom Williams had given him a card of introduction.  The upshot had been that he had called up Chicago and talked for a long time with Professor Clark, a former classmate of ours who was now in the technology school of the university out there.  Kennedy and Clark had been in correspondence for some time, I knew, about some technical matters, though I had no idea what it was they concerned.

“There’s one thing we can always do,” I remarked as we walked slowly over to the laboratory from our apartment.

“What’s that?” he asked absent-mindedly, more from politeness than anything else.

“Arrest every one with a Van Dyke beard who goes on the boat to-morrow,” I replied.

Kennedy smiled.  “I don’t feel prepared to stand a suit for false arrest,” he said simply, “especially as the victim would feel pretty hot if we caused him to miss his boat.  Men with beards are not so uncommon, after all.”

We had reached the laboratory.  Linemen were stringing wires under the electric lights of the campus from the street to the Chemistry Building and into Kennedy’s sanctum.

That night and far into the morning Kennedy was working in the laboratory on a peculiarly complicated piece of mechanism consisting of electromagnets, rolls, and a stylus and numerous other contrivances which did not suggest to my mind anything he had ever used before in our adventures.  I killed time as best I could watching him adjust the thing with the most minute care and precision.  Finally I came to the conclusion that as I was not likely to be of the least assistance, even if I had been initiated into what was afoot, I had as well retire.

“There is one thing you can do for me in the morning, Walter,” said Kennedy, continuing to work over a delicate piece of clockwork which formed a part of the apparatus.  “In case I do not see you then, get in touch with Williams and Carroll and have them come here about ten o’clock with an automobile.  If I am not ready for them then I’m afraid I never shall be, and we shall have to finish the job with the lack of finesse you suggested by arresting all the bearded men.”

Kennedy could not have slept much during the night, for though his bed had been slept in he was up and away before I could see him again.  I made a hurried trip downtown to catch Carroll and Williams and then returned to the laboratory, where Craig had evidently just finished a satisfactory preliminary test of his machine.

“Still no message,” he began in reply to my unspoken question.  He was plainly growing restless with the inaction, though frequent talks over long-distance with Chicago seemed to reassure him.  Thanks to the influence of Williams he had at least a direct wire from his laboratory to the city which was now the scene of action.