I would be interested in your thoughts on the test described in Nidah 59b to check whether a hole in a Kli Cheres lets in water, by inverting in and putting in a larger vessel then filling with water:
(1) Practically, how would this test be done, i.e. how would we know if water
has come in (maybe with some cotton wool inside? or looking for air
bubbles?) - presumably we wouldn't be able to see in.
(2) Presumably we are assuming no water leaks in under the edge of the inner
Keli. Possibly if it is exactly vertical, the air inside will stop water
entering.
(3) I was trying to think about the comparison with the previous suggestion
of the Gemoro (omud aleph) about pushing an empty Keli into water, whether
there is actually a greater force pushing through the hole or not. (There
would be an initial requirement to break the surface tension).
With brochos for your continued Hatzlocho as we approach the Grand Siyum HaShas and prepare to start another cycle!
Mark Bergman
Manchester UK
(1) Air bubbles would seemingly be a good indicator.
(2) You are obviously correct when you state that the Kli has to be the type that would cooperate during the experiment, meaning that no water would be able to get in otherwise.
(3) It seems from the Gemara's terminology "v'Nosen Kedeirah le'Socha" -- "and he puts the pot in it" that the pot is simply placed into the water, not gently placed and not placed on top of (meaning just touching) the water. The Tana Kama must have determined that this amount of pressure shows whether or not there is a practical hole in the Kli Cheres regarding Tumah and Taharah.
All the best,
Yaakov Montrose