(Mishnah): Half a loaf is the Shi'ur for Beis ha'Menuga. If one eats a quarter loaf of Tamei food, he is disqualified [from eating Terumah].

(Beraisa): Half of this (an eighth of a loaf) is the Shi'ur for Tum'as Ochlim [for a food to be Metamei other food or drink. Others explain that it is the Shi'ur to be Mekabel Tum'ah mid'Oraisa, or to receive Hechsher.]

Question: Why did our Tana omit this?

Answer: Tana'im argue about the Shi'ur. (Tosfos R. Peretz - all agree that the Shi'ur is an egg. The Beraisa is R. Shimon, but according to R. Yochanan this is a sixth of a loaf. Rashi - each Tana measures according to his loaf. R. Yochanan says that the Shi'ur is three quarters of an egg, and R. Shimon says that it is an egg. However, it is not exactly half the Shi'ur to disqualify from Terumah, since the latter Shi'ur is not exactly two eggs):

(Beraisa #1 - R. Yehudah): Half a half-loaf to disqualify someone is a bit less than two eggs;

R. Yosi says, it is two eggs Sochakos (slightly bigger than normal).

Rebbi measured and found that it is two eggs and excess.

Question: How much is the excess?

Answer: It is another one part in 20 for each egg.

(Beraisa #2 - R. Noson and R. Dosa): The Shi'ur of an egg [for Tum'as Ochlim] is with the shell;

Chachamim say, it is without the shell.

(Rafram bar Papa citing Rav Chisda): Beraisa #1 is the opinion of R. Yehudah and R. Yosi. Chachamim say that the Shi'ur to disqualify someone is one and a half eggs Sochakos;

Chachamim are R. Yochanan ben Brokah.

Objection: This is obvious! (Rav Chisda taught that half the price of bread is the grocer's mark-up, so R. Yochanan's loaf is a quarter Kav, so a quarter loaf is one and a half eggs!)

Answer: The Chidush is that the eggs are Sochakos.

(Rav Dimi): Someone sent a Se'ah of Na'usah (a place) to Rebbi; Rebbi measured it and found that it was 217 eggs.

Question: What kind of Se'ah is this?

It is not the Se'ah of the Midbar [before they increased the measures], which is 144 eggs;

It is not a Se'ah Yerushalmis [after they increased the measures by a fifth], which is [about] 173 eggs;

It is not a Tzipori Se'ah [after they increased the Yerushalmi measures by a fifth], which is [about] 207 eggs!

Answer #1: Really, it is a Tzipori Se'ah. The giver added the Shi'ur for Chalah [so Rebbi would be left with a Se'ah].

Question: The Shi'ur for Chalah is one part in 24. This is only eight [and a fraction less than one, which the Gemara ignores. R. Chananel's text - this is only nine. (Chalah is one part in 23 of the remaining dough).] The total is still less than 217!

Answer #2: It is a Tzipori Se'ah with the excess of Rebbi (one part in 20. For 207 eggs, this is 10.35).

Question: The total is more than 217!

Answer: Since the excess over 217 it is not a whole egg, it was not mentioned.

(Beraisa): The Yerushalmi Se'ah is a sixth greater than a Se'ah Midbaris. (This is an 'outer sixth, i.e. of the new measure. This is like adding an 'inner' fifth, i.e. of the old measure);

The Tzipori Se'ah is an [outer] sixth greater than a Se'ah Yerushalmis;

It turns out that the Tzipori Se'ah is a third greater than a Se'ah Midbaris.

Question: With respect to what is [the excess] a third?

Suggestion: It is a third of a Se'ah Midbaris.

Rejection: The excess [of 207 over 144] is 63. This is more than 48 (a third of 144)!

Suggestion: It is a third of a Se'ah Yerushalmis.

Rejection: A third of 173 is less than 58. It is not 63!

Suggestion: It is a third of a Se'ah Tziporis.

Rejection: A third of 207 is 69!

Answer #1 (R. Yirmeyah): It means that the excess of a Tzipori Se'ah over a Se'ah Midbaris is [63,] almost a third of itself (69), and a third of itself (69) is almost half a Se'ah Midbaris (72).

Objection (Ravina): The Beraisa does not say 'this is almost this, and this is almost this'!

Answer #2 (Ravina): It means that an [inner] third of a Tzipori Se'ah with the excess of Rebbi (a third of 217, i.e. 72 and a third) exceeds [an outer third, which equals an inner] half of a Se'ah Midbaris (72) by a third of an egg.

(Beraisa): "Reishis Arisoseichem" - the size of your dough;

This refers to the dough people baked in the Midbar (from the Man each day);

The daily ration of Man was "veha'Omer Asiris ha'Eifah Hu." This is the source to obligate taking Chalah from a dough with seven Lugim and excess (an egg and a fifth) of flour,

This equals six Yerushalmi Lugim, which are five Tzipori Lugim.

One who eats this amount [each day] is healthy and blessed. (Ya'avetz - this was for an average person of that generation.) One who eats more than this is gluttonous. If one eats less, his innards are spoiled.

(Mishnah): If Bnei Chatzer forgot to be Me'arev [together] with Bnei Mirpeses (a ladder from the Chatzer leads to a balcony leading to their apartments; each group was Me'arev by itself):

Anything (e.g. a mound at least four Tefachim wide and) 10 Tefachim tall is [permitted] to the Bnei Mirpeses (to transfer between it and their apartments); anything less than 10 is to the Bnei Chatzer.

If a rock or Chulyah of a pit is 10 Tefachim tall, it is to the Bnei Mirpeses. If it is less, it is to the Bnei Chatzer.

This is if these are near the Mirpeses. If they are far away, even if they are 10 tall, they are to the Bnei Chatzer;

Within four Tefachim is called 'near'.

(Gemara): The following are obvious:

If each of two groups was Me'arev by itself,] and each has a Pesach (that is, convenient access to use a common area), this is like a window between two Chatzeros (76a. If it is four by four and they were not Me'arev together, it is forbidden to both of them);

If both can use it through throwing (it is 10 Tefachim above them. Anything this high is inconvenient to use, so it is called throwing - Me'iri. Bach (OC 433:6) - it is inconvenient for heavy things), this is like a wall between two Chatzeros (76b. Both are forbidden);

If both can use it by lowering (it is 10 Tefachim below them, which is inconvenient), this is like a ditch between two Chatzeros (78b. Both are forbidden);

If one has a Pesach and the other can throw, this is like Rabah bar Rav Huna's law (77a. It is permitted only to the group with the Pesach);

If one has a Pesach and the other can lower, this is like Rav Shizbi's law (77a. It is permitted only to those with the Pesach);

Question: If one can throw and the other can lower, what is the law?

Answer #1 (Rav): Both of them are forbidden;

Answer #2 (Shmuel): It is permitted only to the one that can lower, for [relatively] it is convenient for them and inconvenient for the other. In all such cases, it is permitted to the one for which it is convenient.