Shabbat

If one intends to take up his Sabbath abode in a public ground, and places his 'erub  in a pit above ten handbreadths, it is a valid 'erub; if below ten handbreadths, it is not a valid 'erub.  How is this meant? Shall we say, [he placed it] in a pit ten [handbreadths] in depth, and 'above' means that he raised [the bottom] and set it [the 'erub] there;  and 'below' means that he lowered it  and set it there: what is the difference between above and below? He is in one place and his erub in another!  Hence it must surely refer to a pit not ten deep,  and it is taught, it is a valid 'erub, which proves that use with difficulty is regarded as use?  Sometimes he answered him: Both he and his 'erub were in a karmelith,  and why is it called public ground? Because it is not private ground.  And sometimes he answered him: He was on public ground while his 'erub was in a karmelith, this agreeing with Rabbi, who maintained: Whatever is [interdicted] as a shebuth  was not forbidden at twilight.  And do not think that I am merely putting you off, but I say it to you with exactitude.  For we learnt: If there is a water pool and a public road traverses it, if one throws [an object] four cubits therein, he is liable. And what depth constitutes a pool? Less than ten handbreadths. And if there is a pool of water traversed by a public road, and one throws [an object] four cubits therein,  he is liable. Now, as for mentioning this pool twice, it is well; one refers to summer and the other to winter, and both are necessary. For if we were informed [this about] summer, [it might be said the reason] is because it is the practice. of people to cool themselves;  but in winter I would say [that it is] not [so]. And if we were informed this of winter, [it might be id the reason] is because becoming mud-stained  it may happen that he goes down [into the water]; but in summer [I would say that it is] not [so]; thus both are necessary. But why mention traversing, twice? Hence. it must surely follow that a passage under difficulties  is regarded as a [public] passage, whereas use under difficulties is not regarded as [public] use.  This proves it. Rab Judah said: In the case of a bundle of canes: if one repeatedly throws it down and raises it,  he is not liable unless he lifts it up. The Master said: 'A man standing on a threshold may take [an object] from or give [it] to the master of the house, and may take an object] from or give [it] to the poor man.' What is this threshold? Shall we say, a threshold of a public road?  [How state that] he 'may take [an object] from the master of the house'? Surely he [thereby] carries [it] from private to public ground! Again, if it is a threshold of a private domain-[how state that] 'he may take [an object] from the poor man'? Surely he [thereby] carries [it] from public to private ground? Or again if it is a threshold of a karmelith,  — [how state that] 'he may take or give' [implying] even at the very outset? But after all, the prohibition does exist.  Rather it must mean a threshold which is merely a place of non-liability, e.g., if it is not four [handbreadths] square. And [it is] even as what R. Dimi, when he came,  said in the name of R. Johanan: A place which is less than four square, the denizens both of public and private ground may rearrange their burdens upon it, provided that they do not exchange. The Master said: 'Providing that he does not take from the. master of the house and give to the poor man or the reverse, and if he does take and give [from one to the other], the three are exempt.' Shall we say that this refutes Raba? For Raba said: if one carries an object full four cubits  in the street, even if he carries it