"Without tracks?"

"On the ground."

"And at fifty miles an hour?"

"Yes. I have tested her to that speed."

"This, if true, is most extraordinary."

"No, it isn't. I have constructed such machines before."

"I've been told you are an inventor of electrical contrivances."

"Do you doubt the probability of such an engine?"

"Candidly, I do."

"Do you want me to prove it?"