One who throws [an article a distance of] four cubits against a wall, above ten handbreadths [from the ground], it is as though he is throwing in the air; below ten handbreadths [from the ground], it as though he is throwing on the ground. One who throws [an article a distance of] four cubits on the ground is liable. [If] one threw [to a point] within four cubits, but it rolled beyond four cubits, he is exempt; [if he threw] beyond four cubits, but it [then] rolled [back] to within four cubits, he is liable.