h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

No, seriously. How does one throw a curveball? Or a slider? Or any pitch for that matter? I love baseball, but I have no idea how to pitch.

T

To curve any ball in flight, set it spinning in the direction in which you wish it to curve.
To do this with a thrown ball, rotate it as you release it with your thunmb. (Well - it works for cricket).
To exagerate the curve (i.e. cheat) make one half shinnier than the other using vaseline etc.

Okay, so rotate it with my thumb. Cool. I'll have to try that.

*steps outside, fires baseball into snowbank*

Oh well, so much for that idea.

Hand properly on the seams, position varying according to whatever kind of pitch you're going for. Look it up in a manual, I can't explain it with words. The curve is mainly about wrist, which you snap differently to release than a normal throw. It's not really a specialized technique - work it out for your own personal motion. And remember, like all hard-to-hit pitches, a curve screws with your arm, so never forget the ice after throwing more than thirty pitches.

And of course, as mentioned, go for the spit ball if the above doesn't work. Still legal in some leagues... OK, no it isn't.

I've heard that you can throw a curveball by throwing the ball slower than the earth's rotation, and the earth will curve it for you.

..relativity prevents this interesting theory, I'm afraid.
What you want is for one side of ball to be more affected by friction than the other thus slowing it more than the other causing the ball to curve in that direction.

I have to admit that I got the earth's rotation theory from a baseball book, although I forget which one. It was clearly a joke, which makes me think Jay Johnstone wrote it.