I became irritated, and made no reply.

"Answer," he again commanded.

"I have seen its reflection in a glass."

"I say no," he replied; "you have not."

"You are impudent," I exclaimed.

"Not at all," he said, good humoredly; "how easy it is to make a mistake. I venture to say that you have never seen the reflection of the back of your head in a mirror."

"Your presumption astounds me."

"I will leave it to yourself."

He took a hand-glass from the table and held it behind my head.

"Now, do you see the reflection?"