[If] one stretched out his hand, his foot, or a reed into a cistern to ascertain whether it contains water, it is not included in [the law of] ”if [water] is placed”; to ascertain how much water it contains, it is included in [the law of] ”if [water] is placed.”  [If] he threw a rock into the cistern to ascertain whether it contains water, the [water that] splashes is not included in [the law of] ”if [water] is placed”; and that which is on the stone is tahor.

[If] someone beats on a hide; [if it was] outside the water, it is included in [the law of] ”if [water] is placed”; [if it was] inside the water, it is not included in [the law of] ”if [water] is placed.” R’ Yose says: Even [if it was] inside the water, it is included in [the law of] ”if [water] is placed,” since his intention is that it should emerge together with the dirt.

The water that comes up on a boat, in the bilge, or on the oars is not included in [the law of] ”if [water] is placed”; on the traps and various types of nets is not included in [the law of] ”if [water] is placed.” But if he shook them, it is included in [the law of] ”if [water] is placed.”  [If] someone transports a boat to the Great Sea in order to strengthen it, if he takes a nail out to the rain to strengthen it, [or] if he leaves a firebrand in the rain in order to extinguish it, this is included in [the law of] ”if [water] is placed.”

The cover of tables, and the mat of the bricks, are not included in [the law of] ”if [water] is placed.” But if he shook [them, they are included in the law of] ”if [water] is placed.”