A top secret World War II research effort to replace rubber cut off by Japanese expansion in the Pacific produced a bouncing, stretching coral-colored goo that was useless for tires and boots. This deep dive is a biography of Silly Putty, from the disputed parentage of Earl Warrick at Dow Corning and James Wright at General Electric, who each mixed silicone oil with boric acid, to the years it sat in lab drawers as a cocktail party curiosity because it suffered from creep and lacked structural stability.

We follow toy store owner Ruth Fallgatter and marketing consultant Peter Hodgson, who was $12,000 in debt when he borrowed $147 more, packed one-ounce portions into plastic Easter eggs and named it Silly Putty. After a flop at toy fairs, a New Yorker mention sold 250,000 eggs in three days. We explain the physics of a non-Newtonian dilatant ...