Signs of a rabid dog are that its mouth is open, its saliva drips down, its ears are big and folded over, its tail is between its two thighs, it walks on the side [of the path], and [other] dogs bark at it. Some say, also it barks, and its voice is not heard.

Question: What causes a dog to be rabid?

Answer: Rav and Shmuel argued about this. One said that an evil spirit comes upon it. The other said that a woman tests her witchcraft on it.

Germani, the slave of R. Yudan the Nasi, was bitten by a rabid dog. They fed to him from its Chatzer Kaved, and he was not healed.

No one will ever tell you that a rabid dog bit him, and he lived, or that Chavarbar (a kind of snake) bit him and he lived, or that a mule kicked him and the wound healed. This is only if it was a white mule.

Question: What is the source that Safek Nefashos is Docheh Shabbos?

Answer #1 (R. Avahu citing R. Yochanan): "Ach Es Shabsosai Tishmoru'' - [Ach] limits (sometimes we need not observe Shabbos, i.e. in a case of Safek Nefashos).

Answer #2: Some want to say [we know from reasoning]. The Torah said, desecrate one Shabbos for him, and he will observe many Shabbosos.

(R. Ze'ira citing R. Chiya citing R. Yochanan): A Mavuy (alley) that is all Nochrim, and one Yisrael lives there, and a house caved in, we dig it out due to the Yisrael there (perhaps he is there).

Question: Until where [do we uncover him]?

Answer: Two Amora'im [answered this]. One said, until his nose. The other said, until his navel;

[They do not argue.] The one who said until his nose, this is when he is standing (we uncover his nose before his torso. If there is no breath through his nose, surely he is dead.) The one who said until his navel, this is when he is lying (we uncovered from his legs. If we feel his navel and sense that he is not breathing, surely he is dead - HA'GAON RAV C. KANIEVSKY, SHLITA.)

One who is zealous [to be Mechalel Shabbos in order to save a life], he is praiseworthy. [A Chacham] who is asked, he is despised [for not having taught people that Safek Nefashos is Docheh Shabbos]. One who asks, he kills.

(Beraisa): Any matter of danger, we do not say that matters [of Chilul Shabbos] should be done through Nochrim and minors, rather, even through adult Yisraelim (alternatively - great Chachamim).

A case occurred in which a fire erupted in the Chatzer of Yosi ben Simai (the king's overseer) in Sichin [on Shabbos. There was no mortal danger.] People of the kingdom came to extinguish it. He did not let them. He said, the Gabai (Hash-m) will collect His debt (I deserve to suffer this loss);

Immediately, a cloud came there and extinguished it. On Motza'ei Shabbos, he sent to everyone [who came to extinguish] a Sela, and 50 Dinarim to the officer over them.

Chachamim said, he did not need to do so (tell them not to extinguish, since they came by themselves).

A Nochri from Nafti lived in the vicinity of R. Yonah. A fire erupted in the vicinity of R. Yonah. The Nafti wanted to extinguish it. R. Yonah did not let him. [The Nafti] said "in your fate is my property'' (if you do not let me extinguish, you must accept liability for any loss I suffer)! R. Yonah accepted. [Miraculously,] everything was saved.

R. Yudan of the village Ami spread his garment on a stack [on fire], and the fire departed from it.