Explanation: There is no evident division between them, but if there is a Heker, even though the water goes from this side to this side, [Rav Yehudah] is not adamant;

If he were adamant, even an iron wall would not help, like we said above (48b).

Explanation #1: Rashi explains that Beis Shamai require a Mechitzah that divides until the bottom of the pit. This is wrong.

Explanation #2: Rather, it must be 10 Tefachim in the water. Even if the water is very deep and water mixes under the Mechitzah, this suffices according to Beis Shamai, since there is a Heker of a Mechitzah of 10 in the water;

Beis Hillel require a Mechitzah 10 Tefachim outside of the water and a Tefach in the water, like it says "he must submerge the ends of the beams a Tefach in the water."

Explanation #1 (Rashi): The reason why [Rav Yehudah] said that [the Korah] is four wide, is so when you will say [that we view it as if] the edges descend and seal, the space within the Mechitzos will be four, for a Mechitzah made for a space less than four is not considered a Mechitzah.

Inference: He holds that even when it is not four, [Rav Yehudah] would say Pi Tikra Yored v'Sosem from one direction, if the other directions were surrounded by Mechitzos.

Question #1: [Rashi] himself explained (86b) that a Korah of four [Tefachim] permits for water, i.e. a pit between two Chatzeros, and he put [the Korah] on its width in the middle of the pit, above;

According to his words there, why do we need a Korah of four, since the Chatzeros are surrounded by Mechitzos, and we need only to interrupt?

Question #2 (and Explanation #2): We hold like Rav, who says that Pi Tikra Yored v'Sosem, and we hold like Rava against Abaye, that a Korah [permits] due to a Heker, and not due to a Mechitzah;

This is because a Korah that is only a Tefach wide, we do not say Pi Tikra Yored v'Sosem, until it is four wide!

Support: It is proven like this in Shabbos (9a) regarding a porch, that for Pi Tikra [...] we require four wide, regarding what it says "the case is, he covered it with two Koros, and neither is four [wide]";

Strengthening of support: Also according to Abaye, who says that a Korah [permits] due to a Mechitzah, it seems to the Ri that this is only mid'Rabanan, just like the one who says that it is due to Heker;

However, Abaye holds that they would not permit the Mavuy due to a Heker, rather, they made it like a Mechitzah of (i.e. via) Pi Tikra;

"Korah is due to Mechitzah" is unlike "Lechi is due to Mechitzah", which is mid'Oraisa, like we said above (12b), that if a Mavuy was permitted through a Lechi, one who throws into it [from Reshus ha'Rabim] is liable (for mid'Oraisa it is a Mechitzah to make Reshus ha'Yachid).

Implied question: It says above (12b) regarding Rav Yehudah's teaching that a Mavuy that is not proper for Shituf, if it was permitted through a Lechi, one who throws into it is liable. If it was permitted through a Korah, one who throws into it is exempt;

Inference: A Lechi is due to a Mechitzah, and a Korah is [only] due to a Heker!

Answer: It does not mean that you are forced to say that [Korah is] due to a Heker, and not due to a Mechitzah, for even if it were due to a Mechitzah, one who throws into it would be exempt, because it is a Mechitzah only mid'Rabanan!

Rather, it means that Lechi is surely due to a Mechitzah, but Korah, we could say that it is due to Heker.

However, Rav Yakov bar Idi, who challenged Rava from "even further, R. Yehudah said..." that even Korah is due to a Mechitzah, he erred. This is wrong. Even the one who says that it is due to a Mechitzah, this is only mid'Rabanan.

Support: Below (95a), Abaye proved to Rabah from the Beraisa "even further", that two Mechitzos [make Reshus ha'Yachid] mid'Oraisa (according to R. Yehudah), since he permits with [two proper walls and] a Korah on each [other] side, even though Abaye holds that Korah is due to Mechitzah.

Conclusion: Surely, [Korah is a Mechitzah] only mid'Rabanan.

Rebuttal: We could reject this, and say that [Abaye] asked according to Rabah's opinion that [Korah] is due to Heker.

Explanation (Rashi): [Rav Yehudah] holds like R. Yishmael b'Rebbi Yosi, who says that a hanging Mechitzah permits, and the Halachah does not follow him.

Rebuttal #1 (Ri): R. Yishmael permitted only in a Mavuy, but not a hanging Mechitzah in a ruin breached to Reshus ha'Rabim!

Rebuttal #2: A Korah four wide does not permit due to a hanging Mechitzah, for there is no Mechitzah at all, rather, due to Pi Tikra, and we do not find that Tana'im argue about Pi Tikra!

Support: Also Rav, who holds (below, 90b) that Pi Tikra Yored v'Sosem, says here below that a hanging Mechitzah permits only for water.

Explanation (Rashi): [The Makshan] asks only according to Rav Yehudah, who obligates submerging the ends of the beams in water, lest he draw from his friend's Reshus. However, Rav Huna requires only a little Heker, lest he carry there overtly.

Implied question: Why can't we say that Rav Nachman holds like the first Tana, who permits [a Mechitzah] within its Ogen (Chulya, the earth piled up around the pit)?

Answer: "Within its Ogen" that the first Tana said, this is "above" of R. Shimon ben Gamliel. Just like Rav Yehudah requires submerging according to R. Shimon ben Gamliel, the same applies to the first Tana.

Explanation: Similarly, the question "the water mixes under the Korah" is according to Rav Yehudah.

Implied question: Why can't we answer that a Korah permits from its edge and within, but not under the Korah?

Answer #1: Since both have Reshus (rights) under the Korah, if so also next to the Korah should be forbidden, since it mixes with water under the Korah.

Answer #2: It connotes to [the Makshan] that it totally permits, even under the Korah.

Explanation #1 (Rashi): Rav Yehudah is wrong. Rather, Rav Huna is correct. "Above" of Beis Hillel is literally above (it can be near the top of the pit, far above the water).

Remark: People rely on this, that they have privies above water, even though the Mechitzos do not reach to the water.

Implied question: It says below (88a) regarding the Mishnah of a balcony above the water and they made for it a Mechitzah 10 tall... this is only to draw [water], but to spill is forbidden!

Answer: The Halachah follows the other version, that also spilling is permitted, for we follow the lenient opinion in mid'Rabanan laws.

Remark: However, it seems that the Mechitzah made for modesty in the privy, and not for the sake of a Mechitzah over water, for the Halachah does not follow R. Yehudah, who says that the Mechitzah is no greater than the wall between them.

Question: This is astounding, that Rashi explained that the conclusion of our Sugya is unlike Rav Yehudah, for Rav and R. Chiya hold like him, and also the Beraisa of Yakov Karchanai!

Explanation #2: Chachamim were lenient about water, that a Korah permits even if it is not submerged, but a hanging Mechitzah, we could say like Rav Yehudah, that it must be submerged.

Explanation #3 (R. Chananel): we hold like Rav Yehudah. The text does not say "Ela" (for there was no retraction).

Explanation #4: Also R. Tam says that the text does not say Ela. He explains that [the Makshan] challenges Rav Nachman, even according to Rav Huna, who does not require submerging;

It means as follows. A Korah four [Tefachim wide] permits in water, i.e. an irrigation channel or sea, which is a Karmelis, passes by his wall. There is a window below the Korah, and the Korah rests on ledges that protrude from the wall;

[The Makshan] asks "[the bucket] goes to the other side!" Granted, for a pit between two Chatzeros, Mechitzos suffice, each opinion according to what he holds, for it is not Karmelis, rather, Reshus ha'Yachid;

However, an absolute Karmelis, which one cannot be Me'arev, we should be concerned lest [the bucket] go to the other side!

Explanation #4 (cont.): [The Gemara] answers that we have a tradition [that the bucket does not go more than four Tefachim to the side]. It asks that under the Korah, water [from the two sides] mixes, and he draws from Karmelis!

[The Gemara] answers that Chachamim gave this leniency regarding water. The text does not say "Ela", for the answer, that the bucket does not go more than four, remains;

It means as follows. Since the bucket does not go in Karmelis, we are not concerned for mixing of water, for Chachamim were lenient about water through a Mechitzas through [Pi] Tikra [Yored v'Sosem];

This is like it says below (87a) about an irrigation channel for which they made a Mechitzah 10 [Tefachim], and we are not concerned for mixing of water. The same applies here regarding Tikra.

Question #1: [The Gemara] should say that it is because Chachamim were lenient about water!

Question #2: Why did [R. Yochanan] say that R. Yehudah said like R. Yosi's opinion? We should say that all Tana'im who are Machshir a hanging Mechitzah hold like R. Yosi!

Answer: The other Tana'im, we can say that is because [Chachamim] were lenient about water;

However, R. Yehudah would not be so lenient due to water, for he permits even a Mechitzah not made for the sake of water. Therefore, it says that [they were lenient] because Eruvei Chatzeros are mid'Rabanan.

Inference: When there is not in it four by four, one may not draw [from it], but the balcony itself is Reshus ha'Yachid;

Similarly, the balcony in our Mishnah (87b), which taught "one may not draw from it unless he made a Mechitzah 10", the balcony itself is Reshus ha'Yachid, and one may carry in all of it.

Question: Since it does not have Mechitzos, why is it Reshus ha'Yachid? A basket is a Reshus ha'Yachid according to R. Yosi b'Ribi Yehudah only because the walls [of the basket] surround [the pole on which it rests], like it says above (33b)!

Answer #1: Penetration of fish is not penetration (it does not prevent it from being Reshus ha'Yachid), and we say Gud Achis (project the Mechitzos downward). However, regarding a basket there is penetration of goats.

Answer #2: Stam, [the balcony] is open to Reshus ha'Yachid, and it is like holes of Reshus ha'Yachid.

Reference: The Ri elaborated about this below (89b DH Mechitzos) regarding Mechitzos that are not evident.

Question: When there are not four by four Amos, it should be permitted to draw according to Rashi, who explained (below, 94b) that we say Pi Tikra in all four directions!

Answer #1: Here we discuss that they are sloped, like our roofs, so we do not do not say Pi Tikra Yored, like we said above (25b).

Answer #2: The balcony is not even. It is full of indentations all around. There is not an edge here to say Pi Tikra.

Answer #3: There is not a Tefach in the thickness of the balcony.

Inference: Rashi in Sukah (18b), in the Sugya of an Achsadra (a house without four walls) that has pillars, connotes that we say Pi Tikra Yored v'Sosem only if the ceiling is a Tefach thick.