Before Allen Lane began his publishing house in 1935, good books were the purview of the privileged, costing more than many Londoners spent on a week’s rent. But that all changed when Lane, then managing director of the Bodley Head, bought the rights to 10 already popular hardcovers (including Ernest Hemingway’s “A Farewell to Arms” and Agatha Christie’s “The Mysterious Affair at Styles”), redesigning each with a uniform set of specs so simple that even small, inexperienced print shops could mass-produce them on the cheap. The color-coded, pocket-size paperbacks — numbered in the order of their release — were a hit, and Lane’s house, Penguin, eventually became a favorite of collectors eager to snap up everything from coffee mugs to deck chairs bearing its logo. Eighty years on, a cover-to-cover look at the iconic publisher’s ongoing legacy.