Press photos show more than the celebrities of the day. They can also serve as gateways to moments in history that shape our experiences to this day. This photo is labeled “Sennett’s Bathing Girls.” Mack Sennett, an early film entrepreneur whose Keystone Studios launched the careers of movies stars like Harold Lloyd, Gloria Swanson, and his namesake Keystone Cops.

The Bathing Girls were a marketing ploy Sennett created following the logic of the now classic advertising maxim “Sex Sells.” Anne Helen Petersen wrote an article called “Hollywood’s Bathing Beauties” for Lapham’s Quarterly, that traces the genesis of these knee-baring babes.

The way to get Keystone pictures extra notice, Sennet thought, was a healthy dose of knee nudity. The producer put his underlinings to work scouting the area for pretty girls, with particular attention to the look of the bare leg. But these girls, in the rough, weren’t publicity material. Instead, Sennett posed them next to his star comedians and sent the photos off to the press, knowing that the spectacle of the pretty girls and their pretty knees would give his stars the extra coverage they needed. And just in case the newspapers wanted to get sneaky, he had his photographer shot the images in such a way that sneaky editors couldn’t just cut out the comedian and print the pretty girl.

(credit: American Theatre Architecture Archive, Theatre Historical Society of America)