Machshirin 1:6 contains three clauses:
- When someone blows on lentils, the Sages say this counts as b'chi yutan.
- When someone hides their vegetables in a river from thieves, this doesn't count as b'chi yutan.
- When someone floats their vegetables down a river for transport purposes, this doesn't count as b'chi yutan.
Bartenura, following the Rash, explains clause 1 as relating to someone who blew the pile of lentils to see how many blew away (because they were light and thus worthless), but says that this nonetheless counts as b'chi yutan because moisture inevitably leaves the mouth when one blows, and because it's an intrinsic part of the act of blowing it must have been intended.
This of course contradicts the other two clauses, because getting produce wet is also an intrinsic part of dumping it in a river, yet in both of those cases it's considered to be a side effect and not b'chi yutan.
The contradiction is highlighted by Rashash, who favours the alternative explanation by the Rosh (that the blowing is intended to moisten the lentils and see which ones swell).
My edition says that the Chazon Ish, at 2:2 and 3:1, also highlights the contradiction, but constructs a defence of Bartenura's peirush. But I can't quite follow what this defence is. Can anyone help?