George Campbell wrinkled his brows and bent closer above the little enigma in his hands, puzzling helplessly. How could such a thing as this have imbedded in pure rock crystal? Remotely a memory floated through his mind of ancient legends that called quartz crystals ice which had frozen too hard to melt again. Ice -- and wedge-shaped cuneiforms -- yes, didn't that sort of writing originate among the Sumerians who came down from the north in history's remotest beginnings to settle in the primitive Mesopotamian valley? Then hard sense regained control and he laughed. Quartz, of course, was formed in the earliest of earth's geological periods, when there was nothing anywhere but beat and heaving rock. Ice had not come for tens of millions of years after this thing must have been formed.