Mishná sur Les Nombres 15:20

If one had collected hallah [portions] with the intention of keeping them separate, but in the meantime they had become stuck together: Bet Shammai say: they are connected in the case of a tevul yom. But Bet Hillel say: they are not connected. Pieces of dough [of terumah] that had become stuck together, Or loaves that had become joined, or one who bakes a batter-cake on top of another batter-cake before it could form a crust in the oven, or the froth on the water that was bubbling, or the first scum that rises when boiling groats of beans, or the scum of new wine (r. Judah says: also that of rice): Bet Shammai say: they are connected in the case of a tevul yom. But Bet Hillel say: they are not connected. They agree [that they serve as connectives] if they come into contact with other kinds of uncleanness, whether they be of minor or major grades.

Rabbi Eliezer says: the heifer is no more than one year old and the cow no more than two years old. But the sages ruled: the heifer may be even two years old and the red cow even three or four years old. Rabbi Meir says: even five years old, though she is old. But they did not wait with it so long since it might in the meantime grow some black hairs and [thus] become invalid. Rabbi Joshua said: I only heard of [a cow] that was three years old [shelashit]. They said to him: What does "shelashit" mean? He replied: thus have I heard it without any explanation. Ben Azzai said: I will explain: if you say "shelishit" the meaning is ‘the third’ in number to others, but when you say "shelashit" the meaning is one that is three years old. Similarly they said a vineyard that is "revai." They said to him: what does "revai" mean? He replied: thus have I heard it without any explanation. Ben Azzai said: I will explain: if you say "revii" the meaning is the fourth in number to others, but when you say "revai" the meaning is one that is four years old. Similarly it was ruled: if a man ate in an afflicted house half a loaf, three of which can be made from a kav, he becomes unclean. They said to him: say rather "eighteen of which are made of a se'ah." He replied: thus have I heard it without any explanation. Ben Azzai said: I will explain: when you say, three of which are made of a kav it would not contain hallah, but if you say, eighteen of which are made of a se'ah, it has been reduced by its hallah.

Shammai says: “[Dough] of a kav or more is subject to the law of hallah.” And Hillel says: “Of two kavs or more.” But the Sages say: “Neither according to the opinion of this one nor according to the opinion of this one, but [dough of] a kav and a half is subject to the law of hallah.” And after they increased the measures they said: “[Dough of] five quarters is subject. Rabbi Yose said: “Five are exempt, five and more are liable.”

Seven kinds of punishment come to the world for seven categories of transgression:When some of them give tithes, and others do not give tithes, a famine from drought comes some go hungry, and others are satisfied. When they have all decided not to give tithes, a famine from tumult and drought comes; [When they have, in addition, decided] not to set apart the dough-offering, an all-consuming famine comes. Pestilence comes to the world for sins punishable by death according to the Torah, but which have not been referred to the court, and for neglect of the law regarding the fruits of the sabbatical year. The sword comes to the world for the delay of judgment, and for the perversion of judgment, and because of those who teach the Torah not in accordance with the accepted law.