Another thought. If you can hang the ballast outside the cylinder like a canon ball on a chain from the bottom of the cylinder this will do the best job of lowering the center of gravity.
Another thought. If you can hang the ballast outside the cylinder like a canon ball on a chain from the bottom of the cylinder this will do the best job of lowering the center of gravity.
As John indicates, if you have a rod rigidly attached to the bottom of the drum with a weight on the end of the rod equal to the weight of the empty drum, it will float high and vertical, even in waves.
