Mishnà su Genesi 22:13

Ten things were created on the eve of the Sabbath at twilight, and these are they: [1] the mouth of the earth, [2] the mouth of the well, [3] the mouth of the donkey, [4] the rainbow, [5] the manna, [6] the staff [of Moses], [7] the shamir, [8] the letters, [9] the writing, [10] and the tablets. And some say: also the demons, the grave of Moses, and the ram of Abraham, our father. And some say: and also tongs, made with tongs.

What is peret? [Grapes] which fall down during the harvesting. If while he was harvesting [the grapes], he cut off an entire cluster by its stalk, and it got tangled up in the [grape] leaves, and then it fell from his hand to the ground and the single berries were separated, it belongs to the owner. One who places a basket under the vine when he is harvesting [the grapes], behold he is a robber of the poor. Concerning him it is said: “Do not remove the landmark of those that come up (olim)” (Proverbs 22:28).