The professor adjusted his spectacles carefully and nodded. “In normal circumstances, I would have said no, but in view of certain information which has recently come into my hands, it would appear that there is still a chance for us.”

The Chief leaned forward. “Ten days ago, a young Tibetan nobleman arrived in Srinagar, the capital of Kashmir. Ferguson, our local man, took him in charge. Besides possessing valuable information about the state of things in western Tibet at the present time, he was also carrying a letter for Professor Craig. It was from Karl Hoffner.”

Chavasse frowned. “I’ve heard of him vaguely. Wasn’t he some kind of medical missionary in Tibet for years?”

The Chief nodded. “A very wonderful man whom most people have completely forgotten. Remarkably similar career to Albert Schweitzer. Doctor, musician, philosopher, mathematician. He’s given forty years of his life to Tibet.”

“And he’s still alive?” Chavasse said.

The Chief nodded. “Living in a small town called Changu about one hundred and fifty miles across the border from Kashmir. Under house arrest, as far as we can make out.”

“This letter,” Chavasse said, turning to Professor Craig. “Why was it addressed to you?”

“Karl Hoffner and I were fellow students and research workers for years.” Craig sighed heavily. “One of the great minds of the century, Mr. Chavasse. He could have had all the fame of an Einstein, but he chose to bury himself in a forgotten country.”

“But what was in the letter that was so interesting?” Chavasse asked.

“On the face of it, nothing very much. It was simply a letter from one old friend to another. He’d apparently heard that this young Tibetan was making a break for it and decided to take the opportunity of writing to me, probably for the last time. He’s in poor health.”

“How are they treating him?”

“Apparently quite well.” Craig shrugged. “He was always greatly loved by the people. Probably the Communists are using him as a sort of symbol. He said in his letter that he had been confined to his house for more than a year and to help pass the time had returned to his greatest love, mathematics.”