Oh, he's in my laboratory playing with some harmless chemicals.
5 seconds sound clip from Snagglepuss - Fraidy Cat Lion (S1E4).
You can hear this line at 00:00:59.918 in the Blu-ray version of the episode.
Quote context
[...]
- I'm getting awfully hungry, my dear. Will dinner be ready soon?
- Yes, darling. I'm preparing the carrots now.
- We're going to have old-fashioned guillotine stew.
- Mmm, it sounds delicious. Why don't you put in a head... of cabbage?
- Oh, he's in my laboratory playing with some harmless chemicals.
- Heh. I love to read the horror comics. They're delightfully gruesome.
(woman screaming) How thoughtful. She's singing our song.
- Help. A mouse, a mouse! Help. Help me, darling!
- Starve, snarf, starve, snarf.
- Don't worry, darling. I'll go get the cat.
- Do hurry, darling. I can't stand mice.
[...]