Never trust a ball on a hill.....
Some time last year I made a penny ball...basically a bowling ball, with a ton of pennies cemented to it. I posted a picture of it somewhere.
I also had a stand for it to set on...like a gazing ball...redneck yard art
.
Set it in the yard, didn't like it where it was, took it off the stand to move it.
I set it on the level area at the top of the yard.
Not level enough obviously.
Ball took off like a shot, rolled down the hill, just missed nailing the contractors truck in the door by about 2 minutes as he left the neighbors house, hit the railroad ties at the bottom of the hill, went airborn, and is now somewhere buried in the weeds below the septic tank.
I should be able to find it after the frost this fall...if I'm lucky.