Commentary for Bava Batra 4:2
לֹא אֶת הַבּוֹר, וְלֹא אֶת הַדּוּת, אַף עַל פִּי שֶׁכָּתַב לוֹ עֻמְקָא וְרוּמָא. וְצָרִיךְ לִקַּח לוֹ דֶרֶךְ, דִּבְרֵי רַבִּי עֲקִיבָא. וַחֲכָמִים אוֹמְרִים, אֵינוֹ צָרִיךְ לִקַּח לוֹ דָרֶךְ. וּמוֹדֶה רַבִּי עֲקִיבָא, בִּזְמַן שֶׁאָמַר לוֹ חוּץ מֵאֵלּוּ, שֶׁאֵינוֹ צָרִיךְ לִקַּח לוֹ דָרֶךְ. מְכָרָן לְאַחֵר, רַבִּי עֲקִיבָא אוֹמֵר, אֵינוֹ צָרִיך לִקַּח לוֹ דֶרֶךְ. וַחֲכָמִים אוֹמְרִים, צָרִיךְ לִקַּח לוֹ דָרֶךְ:
(He has) not (sold) the bor [a cavity in the ground] nor the duth [a structure of stones above the ground in the form of a bor], even if he wrote (that he is selling) him the depth and the height (of the house). [He does not acquire the bor and the duth since their use (water storage) is distinct from (that of) the house. (They are not acquired) unless he writes "from the bottom of the depths to the heights of the heavens."] And he [the seller] must buy access rights [from the buyer to the bor and the duth. For the seller sells "generously," reserving nothing for himself.] These are the words of R. Akiva. The sages say: He need not buy access rights. [They hold that the seller sells "stintingly," so that when he sold the house, he reserved for himself access rights to the bor and the duth.] And R. Akiva concedes that if he said to him: "Except these" [the bor and the duth], he need not buy access rights, [for, being a superfluous condition, it is understood to refer to access rights.] If he sold them [the bor and the duth] to another, [leaving the house for himself], R. Akiva says that he (the buyer) need not buy access rights, [for the seller sells "generously," and when he sold him the bor and the duth, he also sold access rights.] The sages say that he must buy access rights. [The halachah is in accordance with R. Akiva.]
Bartenura on Mishnah Bava Batra
English Explanation of Mishnah Bava Batra
And he [the seller] must buy himself a path [from the new owner to reach the cellar or cistern], according to Rabbi Akiva. But the Sages say: “He need not buy himself a path.” And Rabbi Akiva agrees that if he had said to him, “Excepting these [the cistern or cellar]” that he need not buy himself a path.
If he sold them [the cellar or cistern] to another, Rabbi Akiva says: “He need not buy himself a path.” But the Sages say: “He must buy himself a path.”
Mishnah two continues to deal with the question which the mishnah began to deal with in mishnah one, when a house is sold what things are sold with and as part of the house?
All of the sages of our mishnah agree that when a person sells another person a house, he has not sold the underground chambers, namely a cistern for storing water, or a cellar used to store food and wine. Even if he wrote that he was selling to the depth of the house, his intent may have been the floor of the house, and not the cellar or cistern. The argument between Rabbi Akiva is over whether or not the seller must buy a path in the house that he sold which will allow him to get to his cellar or cistern. According to Rabbi Akiva, since he sold the whole house, the new owner will have the right to refuse entrance. If the old owner wants to get to his cellar he will need to purchase a path. The Sages disagree. When the person sold the house and did not sell the cellar, we can assume that he intended not to sell a path in the house by which he could reach the cellar. Hence, he does not need to buy a path. Rabbi Akiva agrees with the Sages that if the seller specified to the buyer that he was not selling the cellar or cistern, than he intended on retaining the path and he need not, therefore, purchase the path from the buyer of the house.
Section three discusses the opposite situation, where a person sells a cistern or cellar but not the house. According to Rabbi Akiva, the assumption is that when the seller sold the cistern he intended to sell a path as well, and the buyer need not, therefore, purchase a separate path. According to the Sages, the seller may have sold the cistern or cellar without intending to sell a path by which the buyer could reach them. Consequently, if the buyer wishes to get to his new cellar or cistern he must buy a path as well.