Like all trained microscopists, Rivière worked with both eyes open. The amateur observer has to screw one eye tight in order to avoid a confusion of impressions, and quickly tires himself. The trained man keeps both eyes open, and schools his brain to concentrate on the one vision and ignore the other. He sees only the miniature world at the further end of his complex of lenses.

But Rivière, self-controlled as he was, could not keep attention on his experimental slide. The vision of the miniature world faded out, and through the other eye came the impression of the outside of the polished brass tube of the microscope; the glass slide beyond, lit up by the reflector as though with a searchlight; and the plate-glass bench mirroring the cases of specimens and the shelves of chemical reagents.

And then the material vision of both eyes faded away, and he saw only the inner vision of Elaine lying with bandaged eyes in the darkened room of the Dr Hegelmann's surgical home. The great specialist, pulling at his beard with his long, delicately-chiselled fingers, so out of keeping with the shapelessness of his bulky, untidy figure, had taken Rivière aside and had given him orders in that wonderfully musical voice of his.

"Fraulein is worrying—that is bad for the recovery. I will not have her worried. You must tell her that everything will come right—you must make her smile again."

"But I'm only a casual acquaintance. We met by mere chance a few days before the attack at Nîmes," Rivière had said.

"Nevertheless, you can do much for her. She will listen to you gladly. You are no longer casual acquaintances. I am an observer of human nature as well as a surgeon, and I know that the mind is the key to the bodily health. I know that you can influence her. Talk to her freely—it will not tire her. That is my order."

But Rivière had not been able to carry out the spirit of the old man's shrewd command. When he was by her bedside, a great constraint had come upon him. What had been easy to embody in a letter, was terribly difficult to frame in spoken speech. Several times he had tried to open the way to a confession. He knew it must scarify Elaine, and he shrank from it. But yet it was plain her mind was not at rest, and that was worse for her than the knowledge of the truth.

He, too, must act the surgeon.

With sudden resolution, Rivière put away his microscope and placed his experimental slides in their air-tight incubating chamber. He changed from his laboratory coat to his outdoor coat, and made his way rapidly towards the surgical home.

As he crossed the Wilhelmstrasse—gay with its alluring shops and its crowd of well-dressed, leisured saunterers—a man came up with outstretched hand to Rivière and then hesitated visibly.