Answer #1 (Rav Chisda): Perhaps the Mishnah means 'a hole made by a big drill and Chisumo (an addition made by angling the drill to widen the hole).'

(Rav Tachlifa): Do not say "perhaps". It definitely means this! You may rely on this like on the testimony of Chizkiyah, the father of Ikesh.

(Beraisa): Chizkiyah the father of Ikesh testified to the following law in front of R. Gamliel in Yavneh, in the name of the elder R. Gamliel:

If a Kli Cheres (earthenware vessel) has no interior (it cannot hold anything), it does not have an inside and outside. If either side became Tamei, the entire Kli is Tamei. (Sometimes, only part of a Kli becomes Tamei, e.g. the inside or outside.)

Objection: The Torah teaches that Tum'ah of Klei Cheres depends on the inside. It can become Tamei only if it has an interior!

Answer (R. Yitzchak bar Avin): He means that if a Kli Shetef (a vessel that can become Tahor in a Mikveh, i.e. a wooden (Tosfos - or metal) Kli) is (structurally) like a Kli Cheres without an interior, the Kli Shetef does not have a (Halachic distinction between) inside and outside. I.e. if either part became Tamei, the entire Kli is Tamei.

Question: Why does it attribute the Tum'ah of Klei Shetef to Klei Cheres? It should say explicitly "if a Kli Shetef has no interior... !"

Answer: It teaches (by implication) that if a Kli Shetef has an interior, it is like a Kli Cheres. If the inside became Tamei, also the outside is Tamei. If the inside was not Nitma (even if Tum'ah touched the outside), even the outside is Tahor.

Question: Granted, the Torah taught that this is the law of Klei Cheres. It did not teach this about Kli Shetef!

Answer: Indeed, mid'Oraisa a Kli Shetef has no inside and outside regarding Tum'ah. The Beraisa refers to Tum'ah of liquids, which is mid'Rabanan;

(Mishnah): If a Tamei liquid touched the outside of a Kli, the outside is Tamei, and the inside, brim, and handles are Tehorim;

If a Tamei liquid touched the inside, the entire Kli is Tamei.

Mid'Oraisa, food or drink cannot be Metamei a Kli. Chachamim decreed that liquids can be Metamei Kelim, due to fluids (such as urine and spit) of a Zav or Zavah, which can be Metamei Kelim;

They decreed that liquids can be Metamei Klei Shetef as if they were Klei Cheres. This alerts people that the Tum'ah is only mid'Rabanan, so they will not burn Terumah or Kodshim due to it.

Question: If so, they should also make a distinction for Kelim with an interior for the same reason!

Answer: Since there is a distinction in Kelim without an interior, people know that Tum'ah of liquids is only mid'Rabanan.

Question: Does a Kli Shetef without an interior receive Tum'ah mid'Oraisa [so there was a need to decree about liquids]? We require that it resembles a sack, which is made to be moved empty and full!

Answer: Kelim proper for Midras (for people to sit or lie on are Mekabel Tum'ah mid'Oraisa even without an interior).

Question: If so, they should also decree about Medrasos of Klei Cheres!

Answer: Medras does not apply to Klei Cheres.

Answer #2 (to Question 5:j on Daf 37b - Rav Papa): Beis Hillel refer to a big drill, and Beis Shamai refer to a normal drill.

Inference: Beis Shamai refer to a drill hole smaller than a Sela (that of Beis Hillel);

Objection #1: We understand according to R. Meir (in the coming Mishnah), but not according to Chachamim!

(Mishnah - R. Meir): Beis Shamai refers to a small drill of surgeons;

Chachamim say, they refer to a big drill for piercing walls.

Objection #2: According to R. Meir, Beis Shamai is more lenient than Beis Hillel (a smaller hole is Metaher);

If so, this Mishnah should be in Maseches Eduyos, which teaches every such argument. However, it is not!

Answer #3 (Rav Nachman): A big drill is the size of a Sela Nironis. This (and even a small drill) is more than the size of a regular Sela (Beis Hillel's Shi'ur).

(Mishnah): The following are Mumim in the eye:

The Ris (eyelid) was punctured, Chaser or cracked;

There was in the eye Duk (film), Tavlul, Chalazon(,) Nachash or Etzev (many texts - Inav; these will be explained).

Question: What is Tavlul?

Answer: It is white (of the eye) that breaks through the iris and enters the black (pupil).

(Gemara) Question: What is the Ris?

Answer (Rav Papa): It is the eyelid.

(Mishnah): Duk, Tavlul... (are Mumim).

(Beraisa #1): A Duk (that appears) sunken into the eye is a Mum. A Duk (floating) on the surface is not a Mum.

Contradiction (Beraisa #2): A sunken Duk is not a Mum. A Duk on the surface is a Mum.

Resolution: One Beraisa discusses (a Duk in the) white, and the other discusses (a Duk in the) black.

Objection: Mumim do not apply to the white!

Answer: The resolution means that one Beraisa discusses a white Duk, and the other discusses a black Duk.

(Rabah bar bar Chanah): A sunken black Duk is a Mum. If it is on the surface, it is not a Mum;

A sunken while Duk is not a Mum. If it is on the surface, it is a Mum.

A Siman to remember these is Barka (a spot on the eye. It is white and floats; it is a Mum.)

(Mishnah): Chalazon(,) Nachash or Etzev (Inav, are Mumim).

Question: Are Chalazon and Nachash the same, or does it mean Chalazon or Nachash?

Answer (Rabah bar bar Chanah): R. Yochanan ben Elazar once passed in front of R. Shimon ben Yosi ben Lekunya (the Gadol of his generation);

R. Shimon: Chalazon is a Mum Kavu'a. it is Nachash.

Even though a Chacham may not rule about a Mum in his own animal, he may teach his Talmidim, and they may rule about it. (Now you may permit my Bechor.)

Question: R. Aba taught that if a Chacham teaches a law that affects himself:

If he already taught the law before it affected him, he may rely on his teaching;

If he had not taught the law before it affected him, he may not rely on his teaching!

Answer: R. Shimon had already taught this Mum before.

(Mishnah): Tavlul is white that breaks through the iris...

Our Mishnah is like R. Yosi;

(Beraisa - R. Meir): If white enters the black, or if black enters the white, it is a Mum;

R. Yosi says, the former is a Mum but not the latter, for Mumim do not apply to the white.

(Rav): R. Yosi learns from "Yatza me'Chelev Einemo." (Tosfos - the eye bulges due to an excess of fat; Rashi - a Rasha begins his evil path amidst fatness of the eye, i.e. he desires what he sees);

The white is called fat of the eye. It is not called the eye itself.

R. Meir holds that "Tavlul" refers to anything that is Mevalbel (interrupts) the eye.

(Mishnah): Chavarvar (white spots in the cornea) and (dripping) water are Mumim, if they are Kevu'im (permanent);

Chavarvar is considered Kavu'a if it persists for 80 days.

R. Chanina ben Antigonus says, we check it three times within 80 days.

Water is considered Kavu'a only if a special diet to cure it does not work;

If the animal eats moist (i.e. winter fodder) and (then) dry (summer fodder) of (Beis ha'Ba'al, a field that subsists on) rain or of Beis ha'Shelachin (a field that must be irrigated), the Mum is not established (this is not the proper diet);

It must eat moist after dry.

(Gemara): Our Mishnah is like R. Yehudah:

(Beraisa - R. Meir): Chavarvar is considered Kavu'a after 40 days. Water is Kavu'a after 80 days;

R. Yehudah says, Chavarvar is considered Kavu'a after 80 days.

Eating dry and (then) moist of Beis ha'Shelachin, or moist and (then) dry, is not the proper diet;

It must eat dry after moist (of Beis ha'Ba'al) for three months to establish the Mum.

Question: Our Mishnah establishes a Mum after eating (moist, then dry) from either kind of field! (This is unlike R. Yehudah.)

Answer: The Mishnah is abbreviated. It means as follows:

Eating moist and dry of Beis ha'Ba'al establishes a Mum;

Eating from Beis ha'Shelachin does not establish a Mum;

Even Beis ha'Ba'al does not establish a Mum if it ate moist after dry;

It must eat dry after moist for three months.

Question: Rav Idi bar Avin taught that "moist" is during Adar and Nisan, and "dry" is during Elul and Tishrei (this implies that four months are required)!

Answer: He means, Adar and half of Nisan are moist, Elul and half of Tishrei are dry.

Question: Must it eat moist during the wet months and dry during the dry months, or may both be eaten during the wet months?

Answer: Rav Idi bar Avin taught that "moist" refers to Adar and Nisan, and "dry" refers to Elul and Tishrei. (Each must be eaten in its proper time.)

Rejection: Perhaps all may be eaten in the wet months, as long as the dry was cut during the dry months. (Rashash asks why we do not ask about eating moist during the dry months. Perhaps it is impossible to keep fodder moist all summer.)