Mercer also did other cartoon voices. In the
Popeye cartoons he also voiced Wimpy, Poopdeck Pappy, and Popeye's nephews. For Fleischer's feature film ''
Gulliver's Travels'' he voiced King Little, Twinkletoes the carrier pigeon, and the bumbling spies Sneak, Snoop, and Snitch. He played supporting characters Mr. Bumble and Swat (the Fly) for Fleischer's second feature
Mister Bug Goes to Town. He was also regularly cast with
Pinto Colvig (who voiced
Gabby from ''Gulliver's Travels
and the spinoff Gabby'' film series). Mercer also played numerous supporting characters in Fleischer's
Superman series of 1941–1942. Mercer's natural voice was relatively high-pitched for a man, and he was able to do some of the female voices as well. Beginning in 1958 Mercer also provided all the voices for the
Felix the Cat TV cartoons, including The Professor and Rock Bottom, produced by former Paramount animator
Joe Oriolo. Mercer later worked with Oriolo on
The Mighty Hercules. In addition to his vocal talents, Mercer was also a prolific comedy writer. He wrote hundreds of scripts for various cartoon series at
Paramount, including a number of
Popeye episodes, as well as for television's
Deputy Dawg and
Milton the Monster. Jack Mercer appeared as himself on a 1973 episode of
To Tell the Truth, receiving one of four possible votes. ==Personal life==