Science: The Nearest Thing

In its size and shape, its instincts and intelligence, it was the nearest thing to man that has yet made the perilous voyage into space and returned safely. The occupant of the capsule was a three-year-old, 37-lb. chimpanzee, fired by the U.S. last week on a headlong trip through outer space's underbelly and recovered. The flight was part of the U.S.'s man-in-space program, Project Mercury. When it was over, the historic moment when man himself would speed into space seemed much closer—yet still agonizingly far away.

The booster on the pad at Cape Canaveral...