The Sign of the Miracle
73
I made measurements daily, expecting to see the salamander voltages
climb above those of the frogs as the blastemas formed. It didn't work
that way. The force of the current flowing from the salamanders' am-
putation sites rapidly dropped, while that from the frogs' stumps stayed
at the original level. By the third day the salamanders showed no current
at all, and their blastemas hadn't even begun to appear.
The experiment seemed a failure. I almost quit right there, but some-
thing made me keep on measuring. I guess I thought it would be good
practice.
Then, between the sixth and tenth days an exciting trend emerged.
The salamander potentials changed their sign again, exceeding their nor-
mal voltage and reaching a peak of more than 30 millivolts negative just
when the blastemas were emerging. The frogs were still plugging away
with slowly declining positive voltages. As the salamander limbs regene-
rated and the frog stumps healed over with skin and scar tissue, both
groups of limbs gradually returned (from opposite directions) to the
original baseline of 10 millivolts negative.
THE CURRENT OF INJURY: SALAMANDER VERSUS FROG
Here was confirmation better than my wildest dreams! Already, in my
first experiment, I had the best payoff research can giveāthe excitement
of seeing something no one else seen before. I knew now that