It was nearly four o'clock in the windowless basement laboratory when Horning screwed tight the last connection. He straightened, shrugged the kinks from his back and shoulders, and wiped his hands clean on a wad of waste. Crossing to the battered desk in the corner, he pushed back Margaret's picture, got out pen and paper, and wrote briefly: Dear Myrtle , It's time we faced facts. I never should have married you after Margaret died. My work means everything to me; I can't give it up. But you de