Reference for Bava Batra 172:6

כגון דאמר ליה הין בשנים עשר סלעים לוג בסלע אני מוכר לך וכדאמר רב כהנא שנתות היו בהין ה"נ שנתות היו במדות

Come and hear: If the measure was the property of one of them, he [whose measure it is] acquires successive possession of every single unit of the quantity as soon as it is put in.<span class="x" onmousemove="('comment',' Supra 85a. ');">¹⁵</span> [Surely this law applies] even to [the case] where the measure had not been filled!<span class="x" onmousemove="('comment',' How, then, could it be said that the seller 'may withdraw even at the last se'ah'? ');">¹⁶</span> — [This law refers only to such a case] as when [the seller] said to [the buyer], '[I sell you] a <i>hin</i><span class="x" onmousemove="('comment',' Hin and log are liquid measures, the former containing twelve of the latter. ');">¹⁷</span>

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