Reference for Eruvin 173:2

א"ל אביי ודילמא לא היא עד כאן לא קאמר רבי יהודה התם אלא דאמר גוד אחית מחיצתא אבל כוף וגוד לא

Is it not possible that your observation is incorrect?<span class="x" onmousemove="('comment',' Lit., 'not it'.');">⁴</span> R'Judah may have maintained his view there only<span class="x" onmousemove="('comment',' Lit., 'until here R. Judah only said there', in the case of the wall above the cistern.');">⁵</span> because he holds the principle that a partition is deemed to extend downwards but not here where it must be deemed to be both bent and extended; and R'Hananya B'Akabya may have maintained his view there only, in the case of the sea of Tiberias,<span class="x" onmousemove="('comment',' As is explained infra 87b.');">⁶</span>

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