Reference for Chullin 213:8

האי אריתא דדלאי אין נוטלין ממנו לידים דלא אתו מכח גברא

the waters are then considered as connected<span class="x" onmousemove="('comment',' If he filled this cracked bucket with water from the river and emptied it out into the dike, the water would be running out at both ends, from the crack back into the river and from the mouth into the dike, so that, while the bucket is being emptied out, the water in the dike is actually connected with the water in the river; one may therefore immerse the hands in the dike.');">⁵</span>

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