Comentario sobre Baba Batra 5:11
אָמַר רַבָּן שִׁמְעוֹן בֶּן גַּמְלִיאֵל, בַּמֶּה דְבָרִים אֲמוּרִים, בַּלַּח. אֲבָל בַּיָּבֵשׁ, אֵינוֹ צָרִיךְ. וְחַיָּב לְהַכְרִיעַ לוֹ טֶפַח. הָיָה שׁוֹקֵל לוֹ עַיִן בְּעַיִן, נוֹתֵן לוֹ גֵרוּמָיו, אֶחָד לַעֲשָׂרָה בַּלַּח וְאֶחָד לְעֶשְׂרִים בַּיָּבֵשׁ. מְקוֹם שֶׁנָּהֲגוּ לָמֹד בַּדַּקָּה, לֹא יָמֹד בַּגַּסָּה. בַּגַּסָּה, לֹא יָמֹד בַּדַּקָּה. לִמְחֹק, לֹא יִגְדֹּשׁ. לִגְדֹּשׁ, לֹא יִמְחֹק:
R. Shimon b. Gamliel dijo: ¿Cuándo es esto (lo anterior) así? Con mojado (objetos). Pero con seco, no es necesario. Y él (el vendedor) debe reducir (el saldo) para él (el comprador) un ancho de mano [por el peso de una litra o más, pero no por menos.] Si lo pesó exactamente, le da el excedente adeudado, [ una décima de litra por cada diez litras, que es] de uno a diez [es decir, uno de cada cien] en medida húmeda, y de uno a veinte [es decir, la mitad de una décima por cada veinte litras] en medida seca. En un lugar donde la costumbre es usar una medida pequeña, uno no puede usar una medida grande, [el comprador pierde así, recibiendo solo un "excedente" donde debería haber recibido muchos]; (donde es la costumbre) usar una medida grande, no se puede usar una medida pequeña. Para eliminar [lo que se proyecta por encima del saldo], uno no puede amontonar, [incluso por más dinero]; para amontonar, uno no puede golpear, [incluso por menos dinero.]
Bartenura on Mishnah Bava Batra
English Explanation of Mishnah Bava Batra
[And a shopkeeper] must let the scales sink down a handbreadth [to the buyer’s advantage]. If he gave him an exact measure, he must give him his overweight, a tenth for liquid measures and a twentieth for dry measures.
Where the custom is to measure with small measures they should not measure with large measures and where the custom is to measure with large measures they should not measure with small measures.
Where the custom is to smooth down [what is in the measure] they should not heap it up, and [where the custom is] to heap it up, they should not smooth it down.
Mishnah eleven continues to deal with the weighing of produce.
Section one: Rabban Shimon ben Gamaliel qualifies the statements in the previous mishnah regarding cleaning out measures. These statements applied to measuring liquids, but measures used for dry goods need not be cleaned out with regular frequency, since the dry goods do not stick to the sides.
Section two: The custom was to let the buyer’s side of the scale, which contained the goods, sink one handbreadth lower than the seller’s side. If, however, one did not follow this custom, then the shopkeeper would be obligated to give the buyer either a tenth or a twentieth more than he purchased, depending on the nature of the produce.
Sections three and four: The last two sections teach that one must follow the customs that are typical in one’s place. This is true with regards to the size of the weights as well as the smoothing out or heaping up of the dry goods in the measuring cup. As long as people are consistent in their customs, buyers and sellers will know what they are doing and one will not cheat each other.