MISHNA: With regard to one who rents a cow and a plow in order to plow on the mountain but he plowed in the valley, if the plowshare, the cutting tool on the bottom part of the plow, breaks, he is exempt, as it was even more likely to break on mountainous terrain. In a case where he rents the cow and a plow to plow in the valley but he plowed on the mountain, if the plowshare breaks he is liable. If he hired the cow to thresh legumes but it threshed grain, and the cow slipped and broke its leg, he is exempt. If he hired it to thresh grain but it threshed legumes he is liable, because legumes are slippery.

GEMARA: The mishna discussed the liability of a renter who diverged from the terms of the rental agreement, but it does not teach the halakha of liability for broken machinery in a case where the renter did follow the agreement. The Gemara asks: In a case where the renter did not diverge from their agreement, who pays? Rav Pappa said: The one who holds the goad [parasha] pays, as it can be assumed that he caused the plow to break by not leading it in a straight path. Rav Sheisha, son of Rav Idi, said: The one who holds the vessel, the plow itself, pays. And the halakha is that the one who holds the vessel pays. And if it was a place where rocks are commonly found they both pay, as in this case any small irregularity in the ground where the plow digs a furrow is likely to cause the plow to break.

§ Rabbi Yoḥanan says, citing the Tosefta (Bava Batra 4:6): In a case of one who sells a cow to another and says to him: You should know that this cow has defects, it is accustomed to goring, it is accustomed to biting, it is a kicker, it lies down habitually; but in reality it had only one defect and he inserted it among the list of defects that it did not have, this is a mistaken transaction, as the buyer saw that it did not have the other defects and therefore did not take seriously any of the defects the seller enumerated, including the one that the cow actually had. But if the seller stated: The animal has this defect, i.e., the defect that it in fact has, and other defects, without specifying what they were, this is not a mistaken transaction.

The Gemara notes that this is also taught in a baraita (Tosefta, Bava Batra 4:3): With regard to one who sells a maidservant to another and says to him: This maidservant is an imbecile, she is epileptic, she is crazy [meshuamemet]; but in reality she had only one defect and he inserted it among the other defects, this is a mistaken transaction. But if the seller stated: The maidservant has this defect, i.e., the defect that she in fact has, and other defects, without specifying what they were, this is not a mistaken transaction.

Rav Aḥa, son of Rava, said to Rav Ashi: If the animal had all of these defects, what is the halakha in that case? Can the buyer claim to have thought that the seller was not serious when he mentioned so many problems? Rav Mordekhai said to Rav Ashi: We say this halakha in the name of Rava: If the animal had all of these defects, it is not a mistaken transaction, as he was forthright. The seller is not at fault if the buyer did not believe him.

MISHNA: With regard to one who rents a donkey in order to bring wheat on it, to transport it on its back, and he brought upon it an identical weight of barley, which is lighter than wheat, and the donkey was injured, he is liable. Similarly, if he hired it for transporting grain, and he brought straw of the same weight upon it, he is liable, because the extra volume is as difficult for the animal as the load itself. If he rented a donkey in order to bring on it a letekh, i.e., a measurement of volume, of wheat, but he brought a letekh of barley, he is exempt, as he brought the same volume of a lighter substance. And one who adds to a load a greater volume than he stipulated is liable. And how much must he add to the load for him to be liable? Sumakhos says in the name of Rabbi Meir: A se’a on a camel and three kav on a donkey.

GEMARA: It was stated that amora’im disagreed about the precise text of this mishna. Abaye said that we learned in the mishna: Difficult as the load. Rava said that we learned: Difficult for the load. The Gemara explains: Abaye said that we learned: Difficult as the load, with the meaning that volume is like weight, and therefore when the volume of the two substances is equal, if one adds three kav he is liable. Rava said that we learned: Difficult for the load, with the meaning that if one weight is like the other weight, then the difference in volume is considered an addition. In other words, one is liable if the weight of the barley is the same as that of the wheat, in which case the additional volume is considered to cause damage. Rava holds that if the volume of the two is equal, one is not liable for the additional three kav of weight.

The Gemara attempts to cite a proof for one of these opinions. We learned in the mishna: If one hired a donkey to bring a letekh of wheat, but he brought a letekh of barley, he is exempt. And one who adds to a load a greater volume than he stipulated is liable. What, is it not correct that this means he did not bring exactly a letekh of barley, but added three kav, which would support the opinion of Abaye? The Gemara refutes this interpretation: No, he added a whole se’a. The Gemara asks: But the continuation of the mishna was taught concerning this case: How much must he add to the load for him to be liable? Sumakhos says in the name of Rabbi Meir: A se’a on a camel and three kav on a donkey.

The Gemara explains that this is what the last clause of the mishna is saying: In a case where the renter did not diverge from their agreement, e.g., they stipulated that he would bring wheat and he brought wheat, or barley and he brought barley, how much must he add to the load for him to be liable? Sumakhos says in the name of Rabbi Meir: A se’a on a camel and three kav on a donkey.

The Gemara further suggests: Come and hear a proof from a baraita: If one hired a donkey to bring a letekh, i.e., fifteen se’a, of wheat, but he brought