Cartoons within cartoons are always fun. Porky’s Preview is a silly parody of animation. And one of the best bits ever on The Simpsons was Krusty’s substitute short ‘Worker and Parasite.’
The concept wasn’t used much on Hanna-Barbera cartoons, though the one that may come immediately to mind is the episode of The Jetsons where Elroy’s classmate is watching the one-billionth rerun of The Flintstones. But a better example may be in the Pixie and Dixie short Cousin Tex, which opens with the mice watching ‘Knockout Mouse.’
This little sequence shows that you can animate anything. These are nothing but stick figures, like in Porky’s Preview, and Carlo Vinci still employs the old principle of squash and stretch that you’d find in old Warners shorts. See how the shape of the cat’s head changes. The body even reacts. Think you’d see that in Hanna-Barbera cartoons in the ‘70s?
As an added bonus, we get a little run cycle animated on ones.
Here it is, slower than in the actual cartoon. I like the way the cat’s outline tie moves as he’s running.
Since you’re curious, the music played during the whole ‘Knockout Mouse’ sequence is TC-42 Rural (registered with BMI as “Rural Stage”) credited to Bill Loose and John Seely. It was one of the rare times being used in an H-B cartoon (see comment below).