Reference for Eruvin 48:2

אמר רב אשי ודחזיין לתשמישתא נמי לא אמרן אלא שאין בעומקו יותר מבית סאתים אבל אם יש בעומקו יותר מבית סאתים אסור

R'Ashi ruled: Even<span class="x" onmousemove="('comment',' Lit., 'also'.');">³</span> where it is fit for use the ruling applies only where the layer of water<span class="x" onmousemove="('comment',' That was ten handbreadths deep.');">⁴</span> does not extend<span class="x" onmousemove="('comment',' Lit., 'that there is not in its depth'. A depth of ten handbreadths of water is subject in this respect to the laws of seed. On the question irnt tk whether the greater, or lesser part of the layer of water was ten handbreadths in depth v. Tosaf. s.v. a.l.');">⁵</span>

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