Lyric discussion by Mojos 

Cover art for Scream Thy Last Scream lyrics by Pink Floyd

I don't think the lyrics ever made sense. Syd's genius has always been in part his child-like rhymes and this is a perfect example. But the true genius here is the chipmunk voice. It's awesome and gives the whole thing a cool spooky vibe, much like a cute doll or a clown in a horror movie.