"Now I will tell you how to account for that belief;" said the professor. "It was not so much that you could be sure the _green_ light was up, as that you could not distinguish any difference between the one you saw, and the one you were accustomed to see. You could not discern the difference, I say, and therefore you maintained it to be, as you believed, the same one--the green." "This seems plausible enough, as you state it," acknowledged Colonel West, at length. "But pray why should it not be my young friend, Jupp, who was mistaken--and not I?" The professor shook his head. "I am quite sure that this gentleman"--indicating Oliver Jupp--"can never be mistaken in colours or in their shades, so long as he retains his eyesight to see anything: he has the organ very largely developed. I am right, colonel," he added, nodding. "But what do you say to Cooper, the driver?" returned the colonel. "He says the light was green: and everybody agrees that he would only assert what was true." "What he thought was true," corrected Dr. Macpherson. "There is little doubt, in my mind, that Cooper's case will turn out to be like your own--a fact of colour-blindness. He could not distinguish the difference in the light from the ordinary light, and therefore believed it to be the same." "_Both_ of us blind!" exclaimed the colonel, with wide-open eyes. "That would be too good, Mr. Professor." "I said only colour-blind," corrected the professor. "There is not the least doubt that it will turn out to be so." And he carried the opinions of nearly all present with him. It seemed, indeed, to be the only feasible solution of the difficulty; and so the gentlemen said to each other as they dispersed. "I promised to take you in to see my wife," whispered Mr. Lake to the man of science, arresting him as he was departing. Clara was sitting in an easy-chair, a shawl on her shoulders; but she looked up brightly when the professor entered. If the old feeling of secure happiness had not come back again, a portion of it had; and she said to everybody that she was getting well. Mary Jupp was with her. They had felt half scared at the thought of encountering familiarly so renowned a man. He turned out to be a very shy and simple one--in manners, at least; and Miss Jupp, in the revulsion of relieved feeling, nearly talked him deaf. "She's a pretty thing, that young man's wife," observed the professor to Mrs. Macpherson, when he had got back to Guild. "But I'd not like to take an insurance on her life." "I never knew you had turned doctor, prefessor." "It does not require a doctor's eye to see when a blossom's delicate, Betsy. And those delicate blossoms want a vast deal of care."