Mysteries of the parking meter laid bare! Adding to the satisfaction of reading about the often peculiar circumstances from which forty-eight machines, substances, or technologies arose, this deck reproduces the drawings (mostly in cross section) that accompanied their patent application. Some of the drawings are more entertaining than they are comprehensible, but most—the first disc brake (1902), can opener (1870), washing machine (1910), automatic car wash (1962), and safety pin (1849), for example—are as clear as so many bells.
About that safety pin: it was invented as a way of paying off a $15 debt. The inventor’s creditors gave him a piece of wire and told him to make something useful out of it. He sold them the idea for $400; they became millionaires.