“No,” replied Thorndyke; “it is a demonstration. When we were talking this morning it appeared to me that you did not realize the extent to which it is possible to conceal identity under suitable conditions of light. So I arranged, with Polton’s rather reluctant assistance, to give you ocular evidence. The conditions are not favourable⁠—which makes the demonstration more convincing. This is a very well-lighted room and Polton is a very poor actor; in spite of which it has been possible for you to sit opposite him for several minutes and look at him, I have no doubt, very attentively, without discovering his identity. If the room had been lighted only with a candle, and Polton had been equal to the task of supporting his makeup with an appropriate voice and manner, the deception would have been perfect.”

“I can see that he has a wig on, quite plainly,” said I.