Reference for Bava Batra 177:16

ואלא הך קמייתא דמאי

Our Rabbis taught: If he ordered from him three quarters of a pound, he shall not tell him, 'Weigh out for me the three quarters of the pound one by one'.<span class="x" onmousemove="('comment',' As it is impossible to give the exact weight, the seller would be losing the overweight three times, once with each quarter. ');">²³</span> But a pound weight is laid [on the scale] against a quarter of a pound weight with the meat [on the other scale]. Our Rabbis taught: If he ordered from him ten pounds, he shall not say, 'Weigh out for me each [pound] separately and allow overweight [for each].' But all are weighed together and one overweight is allowed for all of them. Our Rabbis taught: The <i>nefesh</i><span class="x" onmousemove="('comment',' [H] the hollow handle in which the tongue of the balance rests. ');">²⁴</span> of a balance<span class="x" onmousemove="('comment',' Big scales, for the weighing of heavy things such as iron and copper, which are suspended from the roof of the house. ');">²⁵</span> must be suspended in the air three handbreadths [removed from the roof from which the balance hangs].<span class="x" onmousemove="('comment',' So that the beam may have sufficient space in which to move without knocking against the ceiling and impeding the free movement of the scales. ');">²⁶</span> And [the scales must be] three handbreadths above the ground.<span class="x" onmousemove="('comment',' To allow for the free movement of the scales and to prevent their knocking against the ground and their consequent re-bounding, which would interfere with proper weighing. ');">²⁷</span> The beam<span class="x" onmousemove="('comment',' To each end of which the ropes are fastened. ');">²⁸</span> and the ropes<span class="x" onmousemove="('comment',' To which the scales are attached. ');">²⁹</span> [must contain a total length of] twelve<span class="x" onmousemove="('comment',' The beam's length must be four handbreadths and that of the two ropes four handbreadths each; total twelve. ');">³⁰</span> handbreadths.<span class="x" onmousemove="('comment',' If the length of these were less, the scales would not easily move, and small variations in weights could not be detected. ');">³¹</span> [The balances] of wool-dealers and glass-ware dealers [must] be suspended in the air two handbreadths [from the ceiling] and two handbreadths above the ground. Their beams and ropes [must contain a total of] nine handbreadths [in length]. [The balance] of a shopkeeper and of a producer<span class="x" onmousemove="('comment',' V. p. 361. n. 5. ');">³²</span> [must] be suspended in the air one handbreadth [from above], and one handbreadth above the ground. The beam and ropes [must be of a total length of] six handbreadths. A gold balance [must] be suspended in the air three fingers from above, and three fingers above the ground. [The length of] its beam and cords I do not know. But what [kind of balance is] that [which has been mentioned] first?<span class="x" onmousemove="('comment',' Since the balances of wool and glass-ware dealers, shopkeepers, producers, and goldsmiths have been specifically mentioned, what kind of balance, then, is the one mentioned first? ');">³³</span> —

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