Wilson Bentley called snowflakes “nature’s wonder gems,” possessing “an infinity of beauty,” and wrote that when they fell, “the mysteries of the upper air are about to reveal themselves.” The self-educated meteorologist was the first person to make a successful picture—“photomicrograph”—of a snowflake in 1885, and the first to claim that no two are alike. He provided strong evidence for this assertion by photographing more than 5,000 “snow crystals” (as he called them), and saw that each was fascinatingly distinct: some flawless in ornate and icy symmetry, others more charming…