Rif Eruvin 27b {Eruvin 82b continues ... 83b}

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27b

{Eruvin 82b continues}
while Rabbi Shimon holds that there are nine meals to a kav.
Rav Chisda said: Deduct a half for the profit of the shopkeeper. {The shopkeeper charges more to ensure a profit of 1/2, and so it is really eight meals to a kav.}
There is still according to one {=Rabbi Yochanan ben Beroka} eight meals to a kav and according to one {=Rabbi Shimon} nine meals to a kav.
This is what it {the brayta} said that their views are almost identical.
Therefore, when we have eight meals to a kav, and each kav is 400 zuz {=a weight measure} in the weight-measure of Kiruan {, Africa}, we have two meals being 100 zuz, for each meal is 50 zuz, which are 57 in the weight of Sefarad.
{Jewish Encyclopedia defines a zuz as 3.585 grams. If this is the same zuz, each meal is 179.25 grams.}

{Eruvin 83b}
The Sages learnt {in a brayta}: {Bemidbar 15:20}:

כ רֵאשִׁית, עֲרִסֹתֵכֶם--חַלָּה, תָּרִימוּ תְרוּמָה: כִּתְרוּמַת גֹּרֶן, כֵּן תָּרִימוּ אֹתָהּ.

20 Of the first of your dough ye shall set apart a cake for a gift; as that which is set apart of the threshing-floor, so shall ye set it apart.

only if it is the size of your dough. And how much is the size of your dough? The size of the dough of the wilderness. And what is the size of the dough of the wilderness? {Shemot 16:36}:

לו וְהָעֹמֶר, עֲשִׂרִית הָאֵיפָה הוּא.

36 Now an omer is the tenth part of an ephah.

From here they say that dough made from 7/4 {of a kav} and more is obligated in {the taking off of} challah, which is equal to six kav of Yerushalayim and five kav of Tzippori.
From this {amount which it is usual to consume in a 24 hour period} it has been inferred that one who eats this much is considered healthy and blessed. More than that, he is glutton, and less than that, he suffers from bad digestion.

Mishna:
If people of a courtyard and people of a gallery {= an upper story of the house} forgot and did not make an eruv, everything that is ten handbreadths high belongs to the gallery, and anything less that this belongs to the courtyard.
If the bank around a cistern, or a rock are ten handbreadths high belongs to the gallery, less than this – to the courtyard.
To what does this apply? To one that is nearby, but when it is far, even ten handbreadths high – to the courtyard. And which is nearby? One that is not distant four handbreadths.