Bava Metzia

GEMARA. R. Johanan said: In three places has R. Judah taught us that one may not benefit from his neighbour's property. One, what we learnt [in the Mishnah]. What is the second? — We learnt: If one gives a dyer wool to be dyed red, but he dyed it black, or to dye it black and he dyed it red; R. Meir said: He [the dyer] must pay him for the wool.  R. Judah said: If the increased value exceeds the cost [of dyeing], he [the wool owner] must pay him the cost; if the cost exceeds the increased value, he must pay him for the latter.  And what is the third? — That which we learnt: If a man repaid a portion of his debt, and then placed the bond in the hands of a third party, declaring. 'If I do not repay the balance within thirty days, return the note to the creditor:'  and the time arrived, and he did not repay. R. Jose maintained: The third party must surrender [the bond to the creditor]. R. Judah ruled: He must not return it.  But whence [does it follow]? Maybe R. Judah states his ruling here,  only because there is blackening [of the walls].  Or, [in the second case] 'to be dyed red, but he dyed it black,' the reason is that he did otherwise [than he was instructed], and we learnt: He who alters [the contract] is at a disadvantage. Again, in the case of one who repaid a portion of his debt, it [the order to the third party] is an asmakta,  and we thus learn that R. Judah holds that an asmakta gives no title. R. Aha b. Adda said on 'Ulla's authority: If the owner of the lower storey wishes to alter [the building materials from hewn] to unhewn stones, he is permitted; [from unhewn stones] to hewn stones, he is forbidden;  [from whole bricks] to half-bricks,  he is permitted; [from half-bricks] to whole bricks, he is forbidden; to ceil it with cedars,  he is permitted; with sycamores.  he is forbidden; to diminish the number of windows, he is permitted; to increase them, he is forbidden; to elevate [the storey], he is forbidden; to decrease its height, he is permitted.  Whereas if the owner of the upper storey wishes to alter to hewn stones, he is permitted; to unhewn stones, he is not permitted; to half-bricks, he is not permitted; to whole bricks, he is permitted; to ceil it with cedars, he is not permitted; with sycamores, he is permitted; to increase the number of windows, he is permitted; to diminish them, he is not permitted; to elevate the [upper storey], he is not permitted; to decrease its height, he is permitted.] What if neither possesses [the wherewithal for rebuilding]?  (It has been taught: When neither possesses [money for rebuilding]. the garret owner has no claim at all upon the land.)  It has been taught: R. Nathan said: The owner of the lower portion receives two-thirds [of the land], and the owner of the upper, one-third. Others say, The owner of the lower portion receives three-quarters, and that of the upper, one-quarter. Rabbah said: Hold fast to R. Nathan's ruling, because he is a judge, and has penetrated to the depths of civil law. By how much does the loft impair the value of the house [i.e., the lower storey]? — By a third.  Therefore he is entitled to a third. MISHNAH. SIMILARLY, IF AN OLIVE PRESS  WAS BUILT IN A ROCK AND ABOVE IT WAS A GARDEN, AND THE ROOF OF THE PRESS WAS BROKEN THROUGH,  THE OWNER OF THE GARDEN CAN DESCEND AND SOW BELOW [ON THE FLOOR OF THE PRESS], UNTIL THE PRESS-OWNER REPAIRS THE VAULTING [TO PROVIDE A SUPPORT FOR THE GARDEN ABOVE]. IF A WALL OR A TREE FELL INTO A PUBLIC THOROUGHFARE AND CAUSED DAMAGE, HE [ITS OWNER] IS FREE FROM LIABILITY. BUT IF HE WAS GIVEN A [FIXED] TIME TO CUT DOWN THE TREE OR PULL DOWN THE WALL, AND THEY FELL: IF WITHIN THE PERIOD, HE IS NOT LIABLE; AFTER THAT PERIOD HE IS LIABLE. IF A MAN'S WALL WAS NEAR HIS NEIGHBOUR'S GARDEN AND IT COLLAPSED [INTO THE GARDEN], AND WHEN HE DEMANDED, 'REMOVE YOUR STONES', HE REPLIED,