How to throw a spitball<br>Put a small amount of saliva or vaseline on the baseball. The object is to create resistance and a change in the uniform weight of the ball to make its motion more unpredictable and difficult to hit. There's no " right place " to put it, since the object is unpredictability, as with a knuckleball.
a spitball has a different uniform weight than a regular ball
( z1 differ :ARG1 ( z2 weight :mod ( z3 uniform ) :domain ( z4 spitball ) ) :ARG2 ( z5 ball :ARG1-of ( z6 regular ) ) )