Oh, just passing by. I heard my name and I couldn't resist shooting a jolly jet through the tiny perforation in that screen.

10 seconds sound clip from Batman (1966) - The Joker Goes to School (S1E15) TV Series.

You can hear this line at 00:12:11 in the Blu-ray version of the movie.

Quote context

[...]

- A little closer, kids, I want you to see that phony flower in his button hole. Sometimes it shoots out water. Sometimes powder. Other times, knock-out gas.

- Hey!

- Holy magician!

- Hello, kiddies, meet The Joker. And no hard feelings.

- Corny, aren't I?

- Joker, what are you doing here?

- Oh, just passing by. I heard my name and I couldn't resist shooting a jolly jet through the tiny perforation in that screen.

- Just passing by, huh? To do what?

- Gimmick another innocent vending machine?

- Oh, there must be bats in your belfry, Batman.

- Has anyone found fingerprints or other evidence?

[...]