"You certainly cannot," I answered. I looked fixedly at him. He was a fine fellow. Intelligence, resolve, endurance, were manifest in his expressive eyes and strong, masculine features.

"I am inclined to believe that I shall be successful," I said, rising and speaking with enthusiasm. "I will agree to do what you wish, and we will leave the results in the Highest Hands. The operation is doubtless a very grave one, but you are a man temperate in all things. You have also abundantly proved that you have a good constitution. With extreme care your life may not be even endangered. In that case you will be, at the worst, only as you are now. At the best you will be yourself once again. If what I think is the case, I can, by the operation which I propose, remove the obstruction which now cuts off from a portion of your brain the necessary life blood which alone can assure its working. In short, I can restore your brain to its normal state. I propose to open the cranial cavity at the exact spot where I think the mischief is."

"Good," replied Mainwaring; "I leave myself in your hands. How soon can you put me right?"

"I must see your wife and your father."

"Will you return with me now to Dover?"

"No," I answered. "You are so far yourself that you do not need me to accompany you. Take the next train to Dover. Tell your father and wife what you have resolved to do. I will take lodgings for you in a quiet street near this, and will perform the operation to-morrow."

A moment or two later Mainwaring left me.

The die was practically now cast. I was going to experiment, and in a daring manner. It was possible that the result might lead to fatal consequences. I knew this possibility; nevertheless, I scarcely feared that it would arise. I had explained everything clearly to Mainwaring—he was willing to accept the risk. If his wife and father were also willing, I would perform the operation on the following day.

That afternoon I took comfortable rooms for my patient in a street adjoining that in which I lived. I also engaged an excellent surgical nurse, in whom I could place perfect confidence. There was then nothing more to do except to await the arrival of the Mainwarings.