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JOHNNY: Why's this rock ROUNDED?
DR. PETER HAFF: Maybe spheroidal weathering? I'd have to look at it...

JOHNNY: It's real SMOOTH, too...
DR. PETER HAFF: Could be a ventifact, eroded by windblown sand...

JOHNNY: Ooo! And it's PLIABLE!
DR. PETER HAFF: That's... that's an old shoe.

JOHNNY: Mmhmm, so you think it's sedimentary?
DR. PETER HAFF: Johnny, when's the last time you had any WATER?