Reference for Eruvin 178:7

אבל אין דיורין על זה ועל זה שניהן מותרין

observed: I have not heard of this ruling.<span class="x" onmousemove="('comment',' Of Samuel, that though the walls cannot be seen from the roof the principle of upward extension is nevertheless upheld.');">¹⁵</span> Said Abaye to him, 'You yourself told it to us, and it was in connection with the following that you told it to us: If a big roof was adjacent to a smaller one,<span class="x" onmousemove="('comment',' The bigger roof projecting on both sides of the smaller.');">¹⁶</span> the use of the bigger one<span class="x" onmousemove="('comment',' For the movement of objects by the occupiers of the house below.');">¹⁷</span>

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