CHAPTER XXI.
THE INSTITUTE AGAIN Some weeks before, on the 13th of June, on the morning after the sitting during which the Weldon Institute had been given over to such stormy discussions, the excitement of all classes of the Philadelphia population, black or white, had been much easier to imagine than to describe.
From a very early hour conversation was entirely occupied with the unexpected and scandalous incident of the night before.

A stranger calling himself an engineer, and answering to the name of Robur, a person of unknown origin, of anonymous nationality, had unexpectedly presented himself in the club-room, insulted the balloonists, made fun of the aeronauts, boasted of the marvels of machines heavier than air, and raised a frightful tumult by the remarks with which he greeted the menaces of his adversaries.

After leaving the desk, amid a volley of revolver shots, he had disappeared, and in spite of every endeavor, no trace could be found of him.
Assuredly here was enough to exercise every tongue and excite every imagination.

But by how much was this excitement increased when in the evening of the 13th of June it was found that neither the president nor secretary of the Weldon Institute had returned to their homes! Was it by chance only that they were absent?
No, or at least there was nothing to lead people to think so.

It had even been agreed that in the morning they would be back at the club, one as president, the other as secretary, to take their places during a discussion on the events of the preceding evening.
And not only was there the complete disappearance of these two considerable personages in the state of Pennsylvania, but there was no news of the valet Frycollin.