Explanation #1 (Rashi): This is a rock on pegs. A Zav sits on it, and a Kli is under the rock. It is Tamei, due to "v'Chol Asher Yihyeh Sachtav."

Question #1: In Toras Kohanim, we learn Even Misma from "v'Chol ha'Mishkav", and we establish the verse "v'Chol Asher Yihyeh Sachtav" above (33a) for Elyono Shel Zav, and in Toras Kohanim, we establish it for Merkav!

Question #2: If we learn from "v'Chol Asher Yihyeh Sachtav", [it should apply] even to Kelim that are not proper for Mishkav u'Moshav;

In Toras Kohanim, it is explicitly proven that Kelim that are not proper for Mishkav u'Moshav do not have even light Tum'ah!

Question #3: Why does it mention Even Misma? The same applies even to a board on pegs!

Question #4: Since it is called Misma, this connotes that it is an expression of Simah (putting)!

Explanation #2 (R. Tam and Rashbam): Even Misma is a big, heavy rock. There are garments under it, and it is so heavy that the weight of the Zav sitting on it and [automatically] on the garments is not noticed;

It has only light Tum'ah, like I explained above.

Support: Now it is fine that below (69b), we bring "v'Hesayis Even Chadah v'Sumas Al Pum Guba...", for it needs putting and bringing, since it is not light to move.

Question #1: In Toras Kohanim, we include Even Misma from "v'Chol ha'Mishkav" due to Mishkav u'Moshav, and in the entire Gemara it connotes that it is due to Masa!

In our Sugya, we exclude it from "veha'Nosei Osam"!

Question #2: Also below (69b), a Mishnah teaches that a [dead] Zav and Zavah are Metamei through Masa until the flesh rots;

The Gemara explains that "Masa" refers to Even Misma.

Question #3: In Shabbos (82b), it says that they argue about Even Misma, and the Mishnah discusses Heset!

Question #4: In the Tosefta in Kelim (6:2), a Beraisa teaches that Tum'ah of a Kli Cheres is only through its airspace and its Heset via an Even Misma;

Heset is Masa, like we say in Chulin (124b) "is carrying not moving?!"

Also, if Heset were due to Mishkav u'Moshav [it would not apply to Kli Cheres, for] it says in Shabbos (84a) that Midras of a Kli Cheres is Tahor! (If so, also its Heset would be Tahor.)

Answer: What is called in the entire Gemara "Masa" is when the hand or foot of the Tahor is under, and the Zav or Dam Nidah is on the rock. It appears that the Tahor carried the Zav or blood;

However, if Kelim are under the rock, and the Zav sits on it, this is due to Mishkav u'Moshav.

Citation (Zavim 5:2 - Mishnah): What is the case? The Zav's finger is under a Nidvach (layer of rocks), and the Tahor is above...

Assertion: It seems that this is "Heset via an Even Misma" of the Tosefta, e.g. the Nidvach presses on the Zav's finger;

If not, it is as if there is air between his finger and the Nidvach, for there is no [reason to impart] Tum'ah at all.

Question: We should say that it is R. Yosi, who said in our Mishnah that dry flesh [of a Mes] is Tahor!

Answer: It is unlike R. Yosi, since it taught crumbled, and it did not teach dry.

Explanation #1 (Rashi): This is difficult for both of them.

Objection: If so, the verse "Oh b'Etzem" is difficult for the Makshan!

Explanation #2: We ask only against Reish Lakish. It is obvious that teeth are not included in "bone".

Explanation: He does not retract from what he said. Rather, he explains bit by bit.

Question: One may not benefit from a Mes, for we learn [a Gezeirah Shavah] "Sham-Sham" from Eglah Arufah!

Answer #1: Tum'ah is more stringent to people. (They would transgress the Isur Hana'ah, but they are careful about Tum'ah);

This is like it says in Yoma (23a) "this teaches that Tum'as Kli was harsher in their eyes than murder."

Answer #2: Skin is not included in "Besar" (flesh) to be Asur b'Hana'ah.

Source: Also Eglah Arufah [from which we learn that a Mes is Asur b'Hana'ah], we know that it is Asur b'Hana'ah only because Kaparah is written regarding it, like regarding Kodshim, and Hana'ah from Kodshim hides is permitted after Zerikah, which is the time of Kaparah.

Support: This explains why regarding Shor ha'Niskal (an ox sentenced to be stoned), we need "Lo Ye'achel" to forbid benefit from its skin, for we do not learn [skin] from "Besaro". (Rashash - in Pesachim (22b), we learn that the skin is forbidden from "v'Ba'al ha'Shor Naki" or from "Es".)

Explanation: [An impression is left, and] Ein Giz'o Machlif (flesh does not grow back like initially. In most texts, these words are part of the Dibur ha'Maschil, but it seems that they should not be, for they are not in our Gemara.)

Question (Rashbam): In Chulin (128b), it says that flesh of a living person is not Metamei b'Ohel. Just like a Mes does not make Chalipin (regenerate), also everything [from a Mes that does not regenerate has Tum'as Ohel]. Flesh regenerates!

Answer (Rashbam): These are not the same. [Our Sugya discusses] Giz'o Machlif, which connotes that it totally returns. Flesh does not do so;

However, "makes Chalipin" connotes that it grows [back] a little, but not [necessarily] totally. Even flesh does so.

Question: Since we learn from bone, the Gemara should say "just like bone does not make Chalipin", and exclude even flesh!

Answer: Perhaps also bone gets stronger or grows a little after it is lacking.

Question: We should say that Dam Nidah is Yochi'ach. It causes a Nidah to be Metamei Mishkav u'Moshav, but we excluded her blood from them above (it does not make a Mishkav u'Moshav)!

Answer: This is not Yochi'ach, since blood has Tum'as Masa, like a Nidah. Likewise, Zov should be like Dam Nidah!

However, Se'ir ha'Mishtale'ach has no Tum'ah at all.

Question: Also for Masa we do not need [a verse] for the same reason, that it is no worse than Shichvas Zera!

We discuss a Zav, and there is an opinion in Bava Kama (25a) that Shichvas Zera [of a Zav] has Tum'as Masa, even without drops of Zivah, from a Kal va'Chomer:

Note: Tosfos asks, according to that opinion, why do we need the verse?

What is Tahor in a Tahor person, i.e. spit, is Tamei in a Tamei person (a Zav). What is Tamei in a Tahor person, i.e. semen, all the more so it should be Tamei in a Tamei person!

Answer: This is not difficult at all. We should not make this Zivah that causes Tum'ah, i.e. the second sighting, worse than if it was semen;

Semen after the first sighting is Tahor from [Tum'as] Masa, for he is not a Zav;

The Gemara means as follows. It is no worse than if this sighting was Shichvas Zera, which has Tum'as Maga, but not Tum'as Masa;

We do not learn from a Kal va'Chomer, for this is not [considered] Tamei in a Tamei person, for he is still not Tamei, just through this sighting he becomes Tamei.

Question: Since we learn Maga without a verse, how can we say that Se'ir ha'Mishtale'ach is Yochi'ach? It is different, for Zov has Tum'as Maga!

We say like this in Chulin (115b) regarding meat and milk. We learn the Isur to eat it from "Anshei Kodesh Tihyun", and Isur Hana'ah from Orlah, from a Kal va'Chomer;

The Gemara asked that we should learn the entire matter from Orlah, and answered that we can say that one who muzzles a cow's mouth and threshes with it, and one who plows with an ox and a donkey [together], are Yochi'ach;

An Aveirah was done with them, and they are permitted even to eat them;

However, now that we learned the Isur to eat [meat and milk] from a verse, we cannot say Yochi'ach, for they are different. Those (what was threshing with a muzzled cow, or grew from a field that an ox and a donkey plowed) are permitted to eat.

Answer: Also Se'ir ha'Mishtale'ach, since it is Metamei others who engage in it, it is not totally Tahor. Its own Tum'ah applies to it. It is as if it has Tum'as Maga, and it is like Zov.

Explanation #1: Kicho is [phlegm] that comes with great Ko'ach (force) from the chest. Ni'o comes from Ninu'a (shaking) a little. So explained R. Tam.

Explanation #2: We could explain also oppositely! Ni'o is from shaking the entire body. Kicho is with little force!

Implied question: Why didn't the Mishnah teach Kicho?

Answer: The Tana was not concerned to elaborate.

Question: Why did he teach Ni'o before spit, which is primary? It (spit) is explicitly written [in the Torah]!

Answer: What is learned from a Drashah (Ni'o) is dearer to the Tana [so he taught it first].

Question: Now [that ba'Tahor teaches that the spit must touch him,] we should learn spit of a Yevamah from here, that it [must] touch [the Yavam]!

Answer: In the Sifri, we expound from a verse that it need not touch him;

Citation (Sifri) Suggestion: Perhaps "v'Yarkah Befanav" teaches that [her spit must be] literally on his face!

Citation (cont.) Answer: "L'Einei ha'Zekenim" [teaches that we require only] spit visible to the judges.