daf bit: Menachot 63

The torah describes several different ways of preparing the meal-offering, all of which are valid. But you have to stick to what you said you'd do: the mishna teaches that if a man said "I take upon myself to bring a meal-offering prepared on the griddle" he can't bring one prepared in a pan or vice-versa. What's the difference between a griddle and a pan? R' Yose the Galilean says the pan has a lid and the griddle does not. R' Chanina b. Gamaliel says the pan is deep and what is prepared in it is spongy, while a griddle is flat and what is prepared on it is hard. And if a man said "I take upon myself to bring a meal-offering baked in an oven" he must not bring what is baked in a stove or on tiles or in the fireplaces of the Arabs. R' Yehudah says a stove is ok. According to notes in the Soncino edition, a stove is a small oven that can hold only one pot, and the fireplace of the Arabs is an improvised fireplace, a cavity in the ground laid with clay. (63a)

Today's daf is 62.