Reference for Eruvin 157:5

רב אשי אמר בית אחריץ קא רמית בשלמא חריץ למיטיימיה קאי אלא בית למיטיימיה קאי:

but is a house also expected<span class="x" onmousemove="('comment',' Lit., 'stands'.');">¹³</span> to be filled up?<span class="x" onmousemove="('comment',' Of course not. Earth or gravel in a house cannot, therefore, be regarded as abandoned unless the owner had specifically expressed his intention to leave it there.');">¹⁴</span> IF A BOARD FOUR HANDBREADTHS WIDE WAS PLACED ACROSS IT. Raba explained: This<span class="x" onmousemove="('comment',' That the board must be four handbreadths wide.');">¹⁵</span>

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