The Sign of the Miracle
71
rise to the nervous system. He then grafted each of these denervated
embryos onto the back of a whole one. The intact embryos furnished the
grafts with blood and nourishment, and the procedure resulted in a little
"parabiotic" twin, normal except for having no nerves, stuck on the
back of each host animal. Yntema then cut off one leg from each of these
twins, and some of them regenerated. Since microscopic examination
revealed no nerves entering the graft from its host, Yntema's experiment
called Singer's conclusions into question.
Dr. Yntema turned out to be one of the nicest gentlemen I've ever
met, but as I entered his office his Dickensian appearance of eminence—
he was tall, thin, elderly, with craggy features, and wore an immac-
ulately starched, long white lab coat—made me feel like a freshman
being called before the dean. But he put me at ease immediately.
"I've read your proposal and think it's most intriguing," he said with
genuine interest.
"Do you really?" I asked. "I've been afraid you would reject it out of
hand because my ideas depend on Singer's work."
"Marc Singer is a good, careful worker," Yntema replied. "I don't
doubt his observations. What I've described is an exception to his find-
ings under special circumstances."
After a long, pleasant conversation about regrowth, nerves, and re-
search itself, he gave me his approval with a word of caution: "Don't get
your hopes up about what you want to do. I don't believe for one minute
that it'll work, but I think you should do it anyway. We need to en-
courage young researchers. Besides, it'll be fun, and maybe you'll learn
something new, after all. Let me know what happens, and if you need
any help, I'll be here. I'll call the people at the VA right away, so get to
work. Good luck."
This was the start of a long friendship. I'm deeply indebted to Chester
Yntema for his encouragement. Had he not believed that research should
be fun, that you should do what you want rather than what's fashion-
able, my first experiment would have been impossible, and this book
would never have been written.
The Reversals
First I found a good supplier of salamanders and frogs, a Tennessee game
warden who ran this business in his spare time. Sometimes the shipment
would contain a surprise, a small snake. I never found out whether he
included them deliberately or by error. At any rate, his animals weren't