Question: The Mishnah says 'above' and 'below' [10. This implies that one place is directly above the other, i.e. a vertical tree. If it leans, it should have said 'higher' and 'lower' than 10!]

Answer: After the tree leans outside of four Amos (before it is 10 Tefachim tall), it becomes vertical.

Question: Even if it is outside of four Amos and above 10, he could take it from there, and carry it over the [horizontal part of the] tree! (When it is below 10, the air above is a Karmelis - Tosfos and old texts of Rashi.)

Answer: The case is, many people adjust loads (on their backs) on the tree [so it is Reshus ha'Rabim], like Ula taught:

(Ula): If a pillar in Reshus ha'Rabim is nine Tefachim tall and many people use it to adjust loads, if one threw something [four Amos] and it landed on the pillar, he is liable.

Question: What is the argument of Rebbi and Chachamim?

Answer (Beraisa - Rebbi): If an Eruv was in a tree above 10 Tefachim, it is invalid;

If it is [above three and] below 10 Tefachim, it is valid, but one may not take it;

If it is within three Tefachim, one may even take it. (The Isur to use trees on Shabbos does not apply below three);

If the Eruv was put in a basket and hung on the tree, even above 10 it is valid. (This will be explained);

Chachamim say, if the Eruv is in any place from where one may not take it, it is invalid.

Question: Which case do Chachamim discuss?

Suggestion: They discuss the Seifa. (It is in a basket hanging on the tree.)

Rejection: If so, they forbid Tzedadim (the sides of something forbidden. If so, this is difficult for Rabah (Shabbos 154a), who permits Tzedadim!)

Answer: They discuss the Reisha. (It is between three and 10.)

Question: How big is the tree?

If it is less than four by four wide, it is Makom Patur!

If it is [at least] four by four, it should not help if the Eruv is in a basket! (It is in a Reshus ha'Yachid.)

Answer #1 (Ravina): The Reisha discusses a tree that is four by four. The Seifa discusses a tree that is less than four, and the basket completes the Shi'ur of four [but not within three Tefachim of the ground, for this would make it Reshus ha'Yachid]. Rebbi holds like R. Meir and like R. Yehudah:

He holds like R. Meir, who says Chokekim Lehashlim. (It is as if part of the basket was carved out and the tree extends there to complete the Shi'ur);

He holds like R. Yehudah who says that the Eruv must be on a place that is four by four, and we do not have this [without the basket. Therefore, it is essential.]

Question: Where did R. Yehudah teach this?

Answer (Beraisa - R. Yehudah): If one inserted a beam in Reshus ha'Rabim and put his Eruv on top of it, it is Kosher only if it is 10 tall and four [by four] wide.

Objection: Just the contrary! If it is less than this, he and his Eruv are both in Reshus ha'Rabim, so all the more so it is valid!

Correction: Rather, if it is 10 tall, it must be four wide on top. (The Eruv must be on a place four by four. Even though it is in Reshus ha'Yachid, since we give four Amos to a Me'arev (like Rava, end of 32b), it is as if also he is in Reshus ha'Yachid);

If it is less than 10, it need not be four wide. (It is as if the Eruv rests on the ground.)

Suggestion: (Ravina says that even though the basket completes the Shi'ur of four, since this is above three Tefachim, it does not make the tree a Reshus ha'Yachid.) This is unlike R. Yosi b'Rebbi Yehudah!

(Beraisa - R. Yosi b'Rebbi Yehudah): If one inserted a pole in Reshus ha'Rabim with a basket (four by four) on top, and one threw something [from Reshus ha'Rabim] and it landed on the basket, he is liable.

Rejection: It is even like R. Yosi;

There, the walls of the basket surround the pole. (We apply Gud Achis Mechitzta to extend them downward.) Here, the walls do not surround the beam. (We say Chokekim Lehashlim to complete the Shi'ur, but we cannot say Gud Achis in addition to this.)

Answer #2 (to Question (e) - R. Yirmeyah): (Really, it is four by four.) When the Eruv is in a basket it is valid, Ho'il (since) one could tilt the basket (while it is hanging and bring the Eruv within 10).