Archive.org hosts an amazing collection of vintage media in the public domain. This animation collection contains lots of early studio animation from the 1920’s-1940’s including Popeye & Betty Boop from the the Fleischer brother’s Inkwell studios & some great Superman cartoons also by the Fleischers. The early experiments and innovations by Inkwell produced some of the first composited film and animation where the characters jump off the page and into the real world, using stopframe techniques. These pioneering ideas are widely used today in the realms of digital animation and filmmaking. A major component of feature film special effects and increasingly in advertising and commercial tv.
Fleischer Studios, Inc., was an American corporation which originated as an animation studio located at 1600 Broadway, New York City, New York. It was founded in 1921 as Inkwell Studios (or Out of the Inkwell Films) by brothers Max Fleischer and Dave Fleischer who ran the company from its inception until Paramount Pictures, the studio’s parent company and the distributor of its films, forced them to resign in April 1942. In its prime, it was Walt Disney Productions’s very first significant competitor and is notable for bringing to the screen cartoons featuring Koko the Clown, Betty Boop, Bimbo, Popeye the Sailor, and Superman. Unlike other studios, whose most famous characters were anthropomorphic animals, the Fleischers’ most popular characters were humans.
source: wikipedia