Regarding this assertion, Abaye said: In the private domain, everyone agrees that the halakha is in accordance with the opinion of Rav Ḥisda, i.e., that the private domain is considered one entity filled from the ground to the sky. However, here this baraita is referring to a special case involving a tree standing in the private domain and its boughs lean into the public domain, and one threw an object from the public domain and it rested upon the boughs of the tree. Rabbi Yehuda HaNasi holds that we say: Cast its boughs after its trunk. The tree’s branches are considered an extension of its trunk, therefore the entire tree is considered a private domain, and one who throws onto it is liable. And the Rabbis hold that we do not say: Cast its boughs after its trunk, and therefore the boughs themselves are not considered to be a private domain, but rather an exempt domain, and one who throws atop them from the public domain is not liable. אָמַר אַבָּיֵי: בִּרְשׁוּת הַיָּחִיד דְּכוּלֵּי עָלְמָא לָא פְּלִיגִי כִּדְרַב חִסְדָּא, אֶלָּא הָכָא — בְּאִילָן הָעוֹמֵד בִּרְשׁוּת הַיָּחִיד וְנוֹפוֹ נוֹטֶה לִרְשׁוּת הָרַבִּים, וְזָרַק וְנָח אַנּוֹפוֹ, דְּרַבִּי סָבַר אָמְרִינַן ״שְׁדִי נוֹפוֹ בָּתַר עִיקָּרוֹ״. וְרַבָּנַן סָבְרִי לָא אָמְרִינַן ״שְׁדִי נוֹפוֹ בָּתַר עִיקָּרוֹ״.
Abaye said: One who threw a round reed barrel into the public domain, and the barrel is ten handbreadths high and its diameter is not six handbreadths wide, is liable. Since its diameter is less than six handbreadths, its area is less than the area of four handbreadths squared. Therefore, this barrel is considered an object, and if he threw it from the private domain to the public domain he is liable. However, if the diameter of the barrel was six handbreadths wide, he is exempt. Since the area of the barrel is greater than the area of four handbreadths squared, it is considered an independent private domain, and he did not perform an act of throwing an object from one domain to another domain. אָמַר אַבָּיֵי: זָרַק כַּוֶּורֶת לִרְשׁוּת הָרַבִּים, גְּבוֹהָה עֲשָׂרָה וְאֵינָהּ רְחָבָה שִׁשָּׁה — חַיָּיב. רְחָבָה שִׁשָּׁה — פָּטוּר.
Rava said: Even if it was not six handbreadths wide he is exempt. What is the reason for this? He is exempt because it is impossible that the ends of the reeds protruding from the weave of the barrel will not extend above ten handbreadths. Consequently, the entire barrel never entered the public domain, as part of it remains in a non-liable place, i.e., ten handbreadths off the ground of the public domain. רָבָא אָמַר: אֲפִילּוּ אֵינָהּ רְחָבָה שִׁשָּׁה — פָּטוּר. מַאי טַעְמָא? — אִי אֶפְשָׁר לִקְרוּמִיּוֹת שֶׁל קָנֶה שֶׁלֹּא יַעֲלוּ לְמַעְלָה מֵעֲשָׂרָה.
If he turned the barrel that is less than six handbreadths wide over on its mouth, i.e., if he threw it with its mouth facing down, even if the barrel was only seven handbreadths and a bit high, he is still liable, as the legal status of this barrel is equivalent to that of any other object that lands there. However, if the height of this barrel was seven and a half handbreadths, he is exempt. Within three handbreadths of the ground, the principle of lavud takes effect: An object within three handbreadths of the ground has the legal status of being connected to the ground. The sides of the barrel extend to the ground and then it is considered as if the barrel already touched the ground of the public domain, even though it is actually still three handbreadths away, while its upper part remains an exempt domain. It is as if this was a barrel higher than ten handbreadths. כְּפָאָהּ עַל פִּיהָ, שִׁבְעָה וּמַשֶּׁהוּ — חַיָּיב. שִׁבְעָה וּמֶחֱצָה — פָּטוּר.
Rav Ashi said: Even if the height of the barrel was seven and a half handbreadths, he is liable, as the sides of the barrel are not considered to be higher than they are in reality. What is the reason for this? The reason is because partitions are made exclusively for the inside of the barrel. The sides of the barrel play no role beyond the barrel itself, and therefore there is no room to extend the sides by means of the principle of lavud. Therefore, if the barrel itself is not higher than ten handbreadths, it is merely an object. רַב אָשֵׁי אָמַר: אֲפִילּוּ שִׁבְעָה וּמֶחֱצָה — חַיָּיב. מַאי טַעְמָא? — מְחִיצּוֹת לְתוֹכָן עֲשׂוּיוֹת.

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Ulla said: A pillar that is nine handbreadths high, standing in the public domain, and many people adjust the burden on their shoulders upon it, and one threw an object from the private domain and it rested atop the pillar, he is liable. What is the reason for this? It is based on this principle: Anything protruding from the public domain: If it is less than three handbreadths off the ground, and the multitudes step on it, it is considered to be part of the ground. If it is from three to nine handbreadths, they, the multitudes, neither step on it nor adjust the burden on their shoulders on it, and it is not considered part of the public domain. However, a protrusion nine handbreadths high, certainly the multitudes adjust the burden on their shoulders on it. Since the multitudes utilize it, it is considered a public domain, despite its height. אָמַר עוּלָּא: עַמּוּד תִּשְׁעָה בִּרְשׁוּת הָרַבִּים וְרַבִּים מְכַתְּפִין עָלָיו, וְזָרַק וְנָח עַל גַּבָּיו — חַיָּיב. מַאי טַעְמָא? — פָּחוֹת מִשְּׁלֹשָׁה מִדְרָס דָּרְסִי לֵיהּ רַבִּים. מִשְּׁלֹשָׁה וְעַד תִּשְׁעָה — לָא מִדְרָס דָּרְסִי לֵיהּ וְלָא כַּתּוֹפֵי מְכַתְּפִי. תִּשְׁעָה וַדַּאי מְכַתְּפִין עִילָּוֵיהּ.
Based on Ulla’s statement, Abaye said to Rav Yosef: A hole in the ground of the public domain, which is several handbreadths deep, what is its legal status? Is it also considered, in accordance with Ulla’s principle, part of the public domain? In general, with regard to the halakhot of Shabbat, there is no distinction between an area elevated above its surroundings and an area depressed below its surroundings. Rav Yosef said to him: And the same is true in a hole; these halakhot apply. Rava said: In a hole, these halakhot do not apply. What is the reason for this? Since use under duress is not considered use, and the use of a pit even if it is nine handbreadths deep is inconvenient, and it is not comparable to a pillar of the same height. אֲמַר לֵיהּ אַבָּיֵי לְרַב יוֹסֵף: גּוּמָּא מַאי? אֲמַר לֵיהּ: וְכֵן בְּגוּמָּא. רָבָא אָמַר: בְּגוּמָּא לָא. מַאי טַעְמָא? — תַּשְׁמִישׁ עַל יְדֵי הַדְּחָק לָא שְׁמֵיהּ תַּשְׁמִישׁ.
Rav Adda bar Mattana raised an objection to Rava’s opinion from that which was taught in a baraita: One whose basket was placed in the public domain and it was ten handbreadths high and four wide, one may neither move an object from it to the public domain nor from the public domain to it, since its legal status is that of a private domain. If it were less than that height, one may carry from it to the public domain and vice versa. The baraita adds: And the same is true for a hole. Is this statement not referring to the latter clause of the baraita: One may carry from a pit which is less than ten handbreadths deep to the public domain? This supports the opinion of Rav Yosef, that a hole is subsumed within the public domain. Rava rejected this: This statement is not referring to the latter clause of the baraita, but rather to the first clause of the baraita: It is like a basket in that one may not carry from a hole ten handbreadths deep to the public domain because it is a full-fledged private domain. However, no conclusion may be drawn with regard to a hole less than ten handbreadths deep. אֵיתִיבֵיהּ רַב אַדָּא בַּר מַתְנָא לְרָבָא: הָיְתָה קוּפָּתוֹ מוּנַּחַת בִּרְשׁוּת הָרַבִּים גְּבוֹהָה עֲשָׂרָה וּרְחָבָה אַרְבָּעָה — אֵין מְטַלְטְלִין לֹא מִתּוֹכָהּ לִרְשׁוּת הָרַבִּים וְלֹא מֵרְשׁוּת הָרַבִּים לְתוֹכָהּ. פָּחוֹת מִכֵּן — מְטַלְטְלִין. וְכֵן בְּגוּמָּא. מַאי לָאו אַסֵּיפָא: לָא, אַרֵישָׁא.
Rav Adda bar Mattana raised another objection to Rava’s opinion from what was taught in a different baraita, which deals with the laws of joining of borders: אֵיתִיבֵיהּ: