(Mishnah): If Reuven sent a fire, and it consumed wood, stones or dirt, he is liable - "when a fire will go and find thorns, and consume a stack, Kamah (standing crop) or the field, the one who burned will pay.''

If [a fire] passed a wall of four Amos, Derech ha'Rabim (a public road) or a river, he is exempt (for what burned on the other side).

(Gemara) Just like thorns burn [quickly], I would know that [one is liable] only for things that normally burn. Therefore, it says "a stack'';

Just like a stack is detached from the ground, I would know only something detached from the ground. Therefore, it says "Kamah'';

Just like these and these normally burn, I would know that [one is liable] only for things that normally burn. What is the source to obligate for scorching a plowed field or rocks? It says "Oh ha'Sadeh.''

Question: The Torah could have written only thorns, Kamah and a field. Why did it need a stack?

Answer - part 1: This is fine for R. Yehudah. He says that one pays for everything in it

Question: According to Rabanan, who say that one pays for a stack of wheat or a stack of barley, why does it say a stack? (This is not answered. We explained this like HAGAHOS R. DINAR.)

(Mishnah): If it passed a wall of four Amos, Derech ha'Rabim or a river, he is exempt.

(Rav): Our Mishnah discusses a fire that goes up, but if it goes along the ground, he is liable.

(R. Yochanan): Our Mishnah discusses a fire that goes along the ground, but if it goes up, he is exempt [if it passed a wall or path of any size].

(Mishnah) Question: If one lit a fire in his own premises (and it spread to his neighbor), how far must it be from the fire to his neighbor [to be exempt]?

Answer #1 (R. Elazar ben Azaryah): It must be like the distance from the middle of a Beis Kor (to the edge, about 137 Amos);

Answer #2 (R. Eliezer): It must be 16 Amos, like Reshus ha'Rabim;

Answer #3 (R. Akiva): It must be 50 Amos;

Answer #4 (R. Shimon): "The one who burned the fire will pay'' - it is according to the fire.

(Gemara) Beraisa: A case occurred in which a fire passed the Yarden river, for it was a severe fire.

Question: How far must [a fire] spread [to be exempt]?

Answer #1 (R. Eliezer): It must be 16 Amos, like Reshus ha'Rabim. At a time of wind, it must be 30 [Amos].

Answer #2 (R. Yehudah): It is 30 Amos. At a time of wind, it must be 50 [Amos].

Answer #2 (R. Akiva): It must be 50 Amos. At a time of wind, it must be 100 [Amos].

A case occurred in Arev (a place) in which a fire passed more than 300 Amos.

When [does the Shi'ur exempt]? It is when [the fire] jumped, but if there was wood available in front of it, or it was going along burning [grass], he is liable even up to a Mil (2000 Amos. This is like R. Shimon - SEDEI YEHOSHUA.)

If it passed a river or irrigation channel, and it is eight Amos wide, he is exempt.