(Mishnah - R. Eliezer): A beehive is like land:

We may write a Pruzbul on it (a lender may empower Beis Din to collect money owed to him by people who own land. This prevents the debts from being cancelled in Shemitah);

It is not Mekabel Tum'ah in its place;

If one took honey from it on Shabbos (b'Shogeg) he is Chayav Chatas, for this is like reaping.

Chachamim say, it is not like land. We may not write a Pruzbul on it. It is Mekabel Tum'ah in its place. If one took honey from it on Shabbos he is exempt.

Rejection (of Answer #1, Sof 65b): This does not show that R. Eliezer argues with the Beraisa;

(R. Elazar): R. Eliezer learns from "va'Yitbol Osah b'Ya'aros ha'Devash". Just like uprooting from a forest is a Melachah, also taking honey from a hive is a Melachah (since the Torah considers it to be attached).

Answer #2 (to Question 3:b:1, 65B): R. Eliezer's opinion about a baker's board is unlike the Beraisa:

(Mishnah - R. Eliezer): If a baker's board was fixed into the wall, it cannot become Tamei;

Chachamim say, it can become Tamei.

Summation of question (3:b, 65b): The Beraisa is not like R. Eliezer. He considers attached Kelim like land, even if they were made and later attached;

Also, it is not like Chachamim. They consider attached Kelim to be like Metaltelim (movable objects), even if they were made after they were attached!

Answer #1: Really, the Beraisa is R. Eliezer. He is more lenient about the board because wooden Kelim that without a container are Mekabel Tum'ah only mid'Rabanan.

Inference: This implies that Mayim She'uvim (water that was in a Keli) disqualifies a Mikveh mid'Oraisa!

Objection #1: The Halachah is, it disqualifies a Mikveh only mid'Rabanan!

Objection #2: R. Yosi ben R. Chanina taught that R. Eliezer and Chachamim argue about a metal board!

Answer #2: Really, the Beraisa is Chachamim. They are lenient about the pipe because Mayim She'uvim disqualifies a Mikveh only mid'Rabanan.

Question: If so, they should be lenient even if it was hollowed out and then attached!

Answer: They are stringent then, for it was considered a Keli before it was attached.

Question (Rav Yosef): If one intended that rain water wash the frame around a millstone, (is this like intention for something detached, i.e.) does the water now Machshir (enable) Peros to become Tamei? (Water is Machshir only if one intended to use to wash an object that was detached.)

According to R. Eliezer, anything attached to the ground is like the ground, so surely the water is not Machshir;

The question is according to Chachamim (Rashbam - of our Mishnah; Tosfos - in the Mishnah of the board).

This question is not resolved.

Rav Nechemyah brei d'Rav Yosef instructed Rabah bar Rav Huna to authorize a certain girl to collect a tenth of her father's estate (for her dowry), even from the frame around a millstone. (This is like R. Eliezer, who considers it like land.)

(Rav Ashi): In Rav Kahana's academy, we collected even from rental of houses.