Reference for Bava Batra 207:10

ורב נחמן אמר נותן שבעת קבין ומחצה לכל כור וכור

— There<span class="x" onmousemove="('comment',' Where the seller is compelled to sell. ');">⁵</span> we deal with the case where land was first<span class="x" onmousemove="('comment',' When the sale was arranged. ');">⁶</span> dear and is now<span class="x" onmousemove="('comment',' When the argument about the surplus is taking place. ');">⁷</span> cheap. [In such a case] the seller is told, 'If you [wish to] give him the land,<span class="x" onmousemove="('comment',' The surplus. ');">⁸</span> give [it] to him at the present cheaper<span class="x" onmousemove="('comment',' While the seller may re-claim, or compel the buyer to purchase the surplus land, the seller, once he had decided to sell, may be compelled by the buyer to take the lower price prevailing at the time. ');">⁹</span> rate'. But has it not been taught: When he gives it<span class="x" onmousemove="('comment',' I.e., the deficiency of land. ');">¹⁰</span> to him, it must be at the rate at which he had bought of him? — That refers to the case where it was first cheap and is now dear.<span class="x" onmousemove="('comment',' In which case the buyer cannot be charged for the deficiency of land a higher price than the one prevailing at the time of the purchase. ');">¹¹</span> IF, THEREFORE. THERE WAS A SURPLUS IN THE FIELD OF AN AREA OF NINE <i>KAB</i>, etc. R. Huna said: The [law of] nine <i>kab</i> spoken of<span class="x" onmousemove="('comment',' In our Mishnah, according to which such an area must be returned to the seller. ');">¹²</span> [applies] even in [the case of] a large valley.<span class="x" onmousemove="('comment',' Provided there was a surplus of nine kab, the area of the sold field does not matter. However large it may be, the surplus of nine kab or more must be returned, since such a surplus may be regarded as an independent field. ');">¹³</span> But R. Nahman said: Seven <i>kab</i> and a half must be allowed for every <i>Kor</i>,<span class="x" onmousemove="('comment',' Whether the surplus is returnable or not depends on its proportion to the area of the field sold. If the surplus is no more than seven and a half kab per kor = 1/4 kab per se'ah = 1/24 of the area of the field, it need not be returned, however large that surplus may be. The larger the field the larger the surplus allowed. ');">¹⁴</span>

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