(Mishnah): If Ba'al ha'Korah (the one carrying a beam) was first, and Ba'al ha'Chavis (the one carrying a barrel) was last (in back), and the barrel broke due to [colliding with] the beam, Ba'al ha'Korah is exempt. If Ba'al ha'Korah stopped, he must pay. If he told Ba'al ha'Chavis 'stop!', he is exempt.

If Ba'al ha'Chavis was first, and Ba'al ha'Korah was last, and the barrel broke on the beam, he is liable. If Ba'al ha'Chavis stopped, he is exempt. If he told Ba'al ha'Korah 'stop!', he is liable.

The same applies if one was carrying a lit lamp, and one was carrying flax (and it caught fire).

(Gemara) Question: Didn't Rav say that [he is exempt only if] he filled the entire [width of] Reshus ha'Rabim [with jugs]?! Did this [barrel] fill Reshus ha'Rabim?

Answer: Since he stopped [without warning, Ba'al ha'Korah could not stop in time, so] it is like a corner (he is exempt, for he did not see the victim).

(Mishnah): If two were going in Reshus ha'Rabim - one was running and one was walking, or both were running, and they damaged each other, both are exempt.

(Gemara - Yosi ha'Bavli): If one was running in Reshus ha'Rabim and he damaged, he is liable, for he deviated from the custom. If it was Erev Shabbos Bein ha'Shemashos, he is exempt.

He is Yosi ha'Bavli, he is Yosi ben Yehudah, he is Yosi Katonta. Why was he called Yosi Katonta? It is because he was the smallest (and last) of the Chasidim.