Reference for Eruvin 114:12

א"ל התם ליכא למימר מלי הכא איכא למימר מלי

are four thousand cubits distant from one another? - 'Yes', the other replied.' But did not R'Huna lay down: If a town is shaped like a bow then if the distance between its two ends is less than four thousand cubits the Sabbath limits are measured from the bow string, otherwise measuring must begin from the arch? '<span class="x" onmousemove="('comment',' Supra 55a q.v. notes.');">²⁷</span> - 'There', the other replied.'

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