MR. PARKER. ...If we accept the principle of acceptable risk in radiation exposure, and there is no alternative today, instead of black and white, we have only infinite gradation of gray from perhaps a black relating to significant over-exposure, grading down but never reaching white. It is beyond our wits to quantify such a scale. Yet the attempt has to be made at least to define bands of gray. The three ranges as used by the Federal Radiation Council, I think, are precisely such an attempt which I have translated into fashionable color terminology with range I being Arcadian gray, range II being Achillean gray, and range III being Augean gray.

REPRESENTATIVE HOSMER. Do you have a color chart with you?

MR. PARKER. I am not able to put precise numbers on these shades of gray but I classify Arcadian gray as pure and clean for the relevant purpose, and Augean gray containing a reference to the well-known stables of history, and the middle range, if I may clarify that, as I recall Achilles, he was pretty sound but he had a couple of weak spots, one on each heel.