Bava Batra

Now if you assume that the space below and above is transferred automatically, what difference does it make if the parapet is ten handbreadths high?  — Since the parapet is ten handbreadths high the roof is reckoned as a separate structure. Rabina said to R. Ashi: Come and hear:  Resh Lakish said: This shows that if a man sells an apartment to another with the stipulation that the top layer still belongs to him, the top layer does still belong to him; and we asked what was the purpose of the new rule laid down by Resh Lakish, and R. Zebid said: [In order to tell us] that if the vendor desires to let out projecting spars from the roof he may do so, and R. Papa said: [In order to tell us] that if he desires to build an upper chamber over the apartment he may do so. Now if you assume that the top layer is not transferred automatically, what does he gain by his stipulation?  — What he gains by the stipulation is the right to rebuild it if it falls in. MISHNAH. [THE VENDOR OF A HOUSE DOES NOT SELL THEREWITH] A WELL OR A CISTERN,  EVEN THOUGH HE INSERTS [IN THE DEED THE WORDS] 'INCLUDING THE DEPTH AND THE HEIGHT'.  HE MUST, HOWEVER, BUY HIMSELF, [IF REQUIRED], THE RIGHT OF WAY [TO THE WELL OR CISTERN]. THIS IS THE RULING OF R. AKIBA, THE SAGES, HOWEVER, SAY THAT HE NEED NOT BUY THE RIGHT OF WAY. R. AKIBA [ON HIS SIDE] AGREES THAT IF THE VENDOR INSERTS [THE WORDS] EXCEPT THESE',  HE NEED NOT BUY HIMSELF A RIGHT OF WAY. IF THE OWNER OF THE HOUSE SELLS THESE TO ANOTHER R. AKIBA SAYS THAT THE PURCHASER NEED NOT BUY A RIGHT OF WAY TO THEM, BUT THE SAGES SAY THAT HE MUST BUY IT. GEMARA. Rabina  as he sat [and studied this section] asked: Is not WELL  identical with CISTERN?  Said Raba Tosfa'ah to Rabina: Come and hear: It has been taught: Both 'well' and 'cistern' are excavations in the soil, only a 'well' is merely dug out,  whereas a 'cistern' is faced with stone.  R. Ashi [also] as he sat [and studied this section] asked: Is not WELL identical with CISTERN? Said Mar Kashisha the son of R. Hisda to R. Ashi: Come and hear: It was been taught: Both 'well' and 'cistern' are excavations in the soil, only a 'well' is merely dug out, whereas a 'cistern' is faced with stone. HE MUST BUY HIMSELF THE RIGHT OF WAY. THIS IS THE RULING OF R. AKIBA. THE SAGES, HOWEVER, SAY THAT HE NEED NOT. [We may assume,] may we not, that the point at issue between them is this,