JF Ptak Science Books Quick Post

This unlikely advertisement was for baseball players with good throwing/pitching skills to enlist in the U.S. Army and throw the newly-design, baseball-weighted and -sized hand grenade.
“The United States Army needed a grenade that would be accident-proof and the baseball bomb has been the result.–Illustrated World, 1916, page 622.
Bob Gibson threw many of these in the 1960’s.

So did this guy a little later on:
