Reference for Eruvin 205:4

ואיבעית אימא הא והא רבנן ולא קשיא כאן באמצע כאן מן הצד

and yet there is no difficulty, sinc the former refers to a break in the middle<span class="x" onmousemove="('comment',' Of the string, when a knot is essential. A loop would not be strong enough. Hence the ruling that A STRING MAY BE TIED UP.');">¹⁰</span> while the latter refers to one at the end.<span class="x" onmousemove="('comment',' Lit., 'at the side', near the pin, where a loop suffices to hold the string in position.');">¹¹</span> And if you prefer I might reply: Both refer to a break in the middle part, but the Master<span class="x" onmousemove="('comment',' R. Simeon the author of the Baraitha.');">¹²</span> holds that<span class="x" onmousemove="('comment',' Though Pentateuchally permitted.');">¹³</span>

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