Reference for Zevachim 42:8

איכא בינייהו מצות שיקוע

and which proves that it was sunk [earlier]? - No: it means that he lowered it [now].<span class="x" onmousemove="('comment',' They heard the sound of it being lowered.');">¹³</span> If he lowered it, would the sound be heard?<span class="x" onmousemove="('comment',' The wheel was unnecessary for this, as one could simply unfasten the rope by which it was held up, whereupon it would fall automatically.');">¹⁴</span>

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