Reference for Eruvin 167:10

כיון דכי מליא שריא כי חסרא נמי שריא אדרבה כיון דכי חסרא אסירא כי מליא נמי אסירא

- R'Isaac son of Rab Judah replied: We are here dealing with the case of a cistern that was full of water.<span class="x" onmousemove="('comment',' The surface being more or less on a level with the gallery and therefore easily accessible to its tenants. Hence its assignment to the gallery.');">²⁰</span> But is it not<span class="x" onmousemove="('comment',' By the using up of the water near the surface.');">²¹</span> being diminished?<span class="x" onmousemove="('comment',' In consequence of which the tenants of the gallery would have to lower their buckets. Why then should the use of the cistern be permitted even in that case?');">²²</span>

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