Within half an hour after leaving his chum, the young motorist was in the Flatiron Building, asking the man on duty at the elevators where he could find Mr. James Arthur Lafitte, the gentleman whom Cameron had mentioned as being interested in the problem of aëronautics. Lafitte, Cameron had told Matt, was a member of the Aëro Club, had owned a balloon of his own, and had made many ascensions from the town of Pittsfield, Massachusetts--which was near Matt’s old home in the Berkshire Hills; but, Cameron had also said, Lafitte had given up plain ballooning for dirigibles, and, finally, had turned his back on dirigibles for heavier-than-air machines. He was a civil engineer of an inventive turn, and with an adventurous nature--just the sort of person Matt would like to meet.