[Avodah] Torah Geography & Dream Brachos

[Gilad Field]

2 unrelated questions:

1) The Gemara, in Bava Basra 25b (it is also in the first perek of
Gittin), wants to prove that Bavel is north of EY by quoting a Pasuk
in Yermiyahu.  Why should we need a pasuk to teach us geography? This
seems a bit strange to me.  Anyone have any thoughts on that?

2) I saw in Sha'arim Metzuyanim B'Halacha (on KSA 50:3) where he
quotes from the Pri HaSadeh (anyone know who he is?) Who says that if
someone makes a bracha in a dream (because he dreamt he was drinking
water) and he wakes up thirsty he needs to make "another" bracha.  He
gives 2 reasons for this: 1) He wasn't a bar chiyuva while he was
sleeping, and 2) the water was not considered "l'fanav" (in front of
him) in that bracha.
I don't have access to the full teshuva - but the whole question
sounds very odd to me.  what would even be the hava amina that a
bracha in a dream could apply to real life?

If anyone has any insight - i would be grateful.

Thanks,
gilad field