James A. Owen said this quote

“ All the various time travel devices used by Verne and Bert were stored in the repository, Poe explained, including the ones that had never quite worked as they were meant to. There was one that resembled a blue police box from London—“Stolen by a doctor with delusions of grandeur,” said Poe—one that was simply a large, transparent sphere—“Created by a scientist with green skin and too much ego,” said Verne—and one that was rather ordinary by comparison.“This one looks like an automobile,” John said admiringly, “with wings.”“The doors open that way for a reason,” Verne explained, “we just never figured out what it was. The inventor of this particular model tried integrating his designs into a car, an airplane, and even a steam engine train. He was running a crackpot laboratory in the Arizona desert, and he never realized that it was not his inventions themselves, but his proximity to some sort of temporal fluctuation in the local topography, that allowed them to work.” “What happened to him?” asked Jack.“He’d get the machines up to one hundred and six miles per hour,” said Bert, “and then he’d run out of fuel and promptly get arrested by whatever constabulary had been chasing him. The sad part was that Jules figured out if he’d just gone two miles an hour faster, he’d likely have been successful in his attempt. ”