Reference for Eruvin 179:1

לנטורי תרביצא הוא דעבידא

that it was made for the purpose of facilitating the watch over his house garden.<span class="x" onmousemove="('comment',' And that he withdrew himself entirely from the use of the roofs.');">¹</span> Rami B'Hama<span class="x" onmousemove="('comment',' Who held Rab's view that on a roof, according to the Sages, objects 'may be moved only within four cubits' (v. supra 89a ad fin.) .');">²</span> enquired: Is it permitted to move an object<span class="x" onmousemove="('comment',' Lit., 'what (law) is it'.');">³</span> two cubits along a roof and two cubits along a column?<span class="x" onmousemove="('comment',' Ten handbreadths high and four handbreadths wide that was standing in the public domain in close proximity to the roof.');">⁴</span> - 'What an enquiry', Rabbah<span class="x" onmousemove="('comment',' MS.M. 'Raba'.');">⁵</span>

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