Science: Still Cooking

Last week—more than six months after the first atomic bomb exploded—the New Mexican soil which melted to greenish glass was still aboil with radioactivity. Fragments weighing only a fraction of an ounce caused a continuous roar when held near a Geiger-Muller counter, a gadget which clicks once when an ionizing particle passes through it. Ionizing particles zoomed out of the fragments so fast that the clicks they made as they passed through the counter could not be distinguished individually.

Pieces of twisted steel from the wreckage were radioactive too. Some of their iron...