"But that wasn't all there was to it. Lung cancer and stomach cancer in particular continued to creep up the statistical tables, far beyond the point which could have been accounted for by better reporting, or by the increase in the average lifespan, either. Then the same thing took place in malignant hypertension, in Parkinsonism and other failures of the central nervous system, in muscular dystrophy, and so on, and so on. It began to look very much as though we'd exchanged a devil we knew for a devil we didn't.

"So there was quite a long search for a possible infectious origin for each of the degenerative diseases. Because some animal tumors, like poultry sarcoma, are caused by viruses, a lot of people set to work hunting like mad for all kinds of cancer viruses. There was a concerted attempt to implicate a group called the pleuro-pneumonia-like organisms as the cause of the arthritic diseases. The vascular diseases, like hypertension and thrombosis, got blamed on everything from your diet to your grandmother.

"And it all came to very little. Oh, we did find that some viruses did cause some types of cancer, leukemia among them. The PPLO group does cause a type of arthritis, too, but only the type associated with a venereal disease called essential urethritis. And we found that the commonest of the three types of lung cancer was being caused by the radiopotassium content of tobacco smoke; it was the lip and mouth cancers that were caused by the tars. But for the most part, we found out just what we had known before that the degenerative diseases weren't infectious. We'd already been down that dead end.

"About there was when Pfitzner got into the picture. The NHS, the National Health Service, got alarmed enough about the rising incidence curves to call the first really major world congress on the degenerative diseases. The U.S. paid part of the bill because the armed services were getting nervous about the rising rate of draft rejections."

"I heard some talk about that part of it," Paige said. "It started right in my own service. A spaceman only has about ten years of active life; after that he's given garrison duty somewhere so we like to catch 'em young. And even then we were turning back a huge proportion of young volunteers for 'diseases of old age, incipient circulatory disease in most cases. The kids were shocked; most of them had never suspected any such thing, they felt as healthy as bulls, and in the usual sense I suppose they were but not for space flight."

"Then you saw one of the key factors very early," Anne said. "But it's no longer a special problem of the Space Service alone. It's old stuff to all the armed services' medical departments now; at the time the NHS stepped in, the overall draft rejection rate for 'diseases of old age' was about 10 per cent for men in their early twenties. Anyhow, the result of the congress was that the U.S. Department of Health, Welfare and Security somehow got a billion dollar appropriation for a real mass attack on the degenerative diseases. In case you drop zeros as easily as I do, that was about half what had been spent to produce