Brachot 53 - Where to say the after-meal prayer
After Shabbat ends, one recites the Havdallah - the separation between Shabbat and a weekday. Here Beit Shammai and Beit Hillel argue whether one should say "Who creates illuminations of the fire" or "illumination of the fire." Incidentally, one should say the blessing on the fire, but not one used for idolatrous purposes, not one lighted for prohibited work during Shabbat, and not one lighted in honor of someone. It should be fire started to give light - since he did not light any fire on Shabbat, and to commemorate Adam, who discovered fire after Shabbat.
One should say the after-meal prayer in the place where he ate. What if he forgot and went away? Beit Shammai say that he should return. Beit Hillel asked them, "If one ate on top of a mansion, and forgot and went down, must he return to say the prayer, even with a great difficulty?" Beit Shammai replied, "If he left a purse with gold, would he not return? How much more so for prayer!"
Rabbah bar bar Chanah was traveling with a caravan. When the caravan came to a stop, he ate and then forgot to recite the after-meal blessing. When the caravan started moving, he recalled this and thought to himself, "What am I to do? If I say that I forgot to say the prayer, they will tell me that God is everywhere." Instead, he told them that he forgot a golden dove. After he came back and prayed, he indeed found a golden dove.
Art: Alberto Pasini - Caravan In The Desert