[If] three women were sleeping in one bed and blood was found beneath one of them, they are all tamei. [If] one of [the women] examined [herself] and found herself to be tamei, she is tamei and the other two are tahor. And they may attribute [the stain] to one another; but if they were unfit to menstruate, we treat them as though they were fit to menstruate.

[If] three women were sleeping in one bed, and blood was found beneath the middle one, all of them are tamei. [If blood was found] beneath the inner one, the two inner ones are tamei and the outer one is tahor. [If blood was found] beneath the outer one, the two outer ones are tamei and the inner one is tahor. R’ Yehudah said: When [is this ruling valid]? When they ascended by the foot of the bed. But if the three of them ascended by going over [the outer one], all of them are tamei.  [If] one of [the women] examined [herself] and found herself to be tahor, she is tahor and the [other] two are tamei. [If] two [of them] examined [themselves] and found themselves to be tahor, they are tahor and the third [woman] is tamei. [If] all three of them [examined themselves] and found themselves to be tahor, all of them are tamei.  To what is this comparable? To a tamei heap that got mixed up with two tahor heaps, and they searched one of [the heaps] and found it to be tahor, it is tahor and [the other] two are tamei. [If they searched] two and found them to be tahor, they are tahor and the third [heap] is tamei. [If they searched] all three of them and found them to be tahor, all of them are tamei; [these are] the words of R’ Meir, for R’ Meir says: Anything that is in a presumptive state of tumah remains forever in its [state of] tumah until it becomes known to you where the tumah is. But the Sages say: He searches until he reaches bedrock or virgin [soil].

Seven detergents are applied to the bloodstain: raw saliva, split-bean water, urine, nesser, boris, kimunia, and ashlag. One immersed [the garment] and prepared tohoros upon it: [If] he applied the seven detergents to [the stain] and it did not come out, it is dye, the tohoros are tahor, and he need not immerse [the garment]. [If the stain] came out or dimmed, it is a bloodstain, the tohoros are tamei, and it is necessary to immerse [the garment].

What is raw saliva? Anyone who has not tasted anything. [What is] split-bean water? Chewed split beans which were sepa-rated from their peels. [What is] urine? That which fermented.  One must scrub [the stain] three times with each and every one [of the detergents]. [If] one applied [these detergents] out of their sequence, or if he applied [all] seven detergents simultaneously, he has not accomplished anything.

[For] any woman who has a fixed period, her time suffices for her.  And these are the fixed periods: She yawns, or sneezes, or she feels pain in the area of her navel, or in her lower abdomen, or she streams [blood], or a type of shivering takes hold of her, and so too similar [symptoms]. If she establishes for herself [any of these symptoms] three times, it is a fixed period.

[If] she was accustomed to experience a [menstrual] discharge at the beginning of the episodes, all the tohoros that she handled for the duration of the episodes are tamei. [If] at the end of the episodes, all the tohoros that she handled for the duration of the episodes are tahor. R’ Yose says: Days and hours also are [established as] fixed periods. [If] she was accustomed to experience a discharge at sunrise, she is forbidden [for cohabitation] only at sunrise. R’ Yehudah says: The entire day is [permitted] for her.

[If] she was accustomed to experience a discharge [every] fifteenth day, and she changed to discharging on the twentieth day, [both] this [day] and that [day] are forbidden. [If] she changed twice to the twentieth day, both this [day] and that [day] are forbidden. [If] she changed three times to the twentieth day, the fifteenth [day] becomes permitted, and she has estab-lished for herself the twentieth day [as her fixed period]. For a woman does not establish for herself a fixed period until she establishes it three times, and she does not become free from a fixed period until it is uprooted from her three times.

Women in their virginity are like vines. There is a vine whose wine is red, and there is a vine whose wine is black, there is a vine whose wine is plentiful, and there is a vine whose wine is meager. R’ Yehudah says: Every vine has wine in it. And that which has no wine, it is a dorketi.

[Regarding] a young girl whose time to discharge [uterine blood] has not arrived and she married, Beis Shammai say: We give her four nights. But Beis Hillel say: [We give her] until the wound heals.  [If] her time to discharge [uterine blood] arrived and she married, Beis Shammai say: We give her the first night. But Beis Hillel say: [We give her] until the [night of the] de-parture of the Sabbath, [altogether] four nights.  [If] she discharged blood while yet in her father’s house, Beis Shammai say: We give her the cohabitation of the mitzvah. But Beis Hillel say: [We give her] the entire first night.

[If] a niddah examined herself on the seventh day in the morning and found [herself to be] tahor, and at twilight she did not separate [in taharah], and after [several] days she examined herself and found [herself to be] tamei, she has a presumption of taharah. [If] she examined herself on the seventh day in the morning and found [herself to be] tamei, and at twilight she did not separate [in taharah], and after [some] time she examined [herself] and found [herself to be] tahor, she has a pre-sumption of tumah. And she conveys tumah [retroactively] for [a period of] twenty-four hours or from examination to ex-amination. But if she has a fixed period, her time suffices for her.  R’ Yehudah says: As long as she did not separate in ta-harah from [the time of] minchah or later, she has a presumption of tumah. But the Sages say: Even [if] on the second day of her niddah period she examined [herself] and found [herself to be] tahor, and at twilight she did not separate [in taharah], and after [some] time she examined [herself] and found [herself to be] tamei, she has a presumption of taharah.

[If] a zav and a zavah examined themselves on the first day and found [themselves to be] tahor, and [again] on the seventh day and found [themselves to be] tahor, but [on] the other days in between they did not examine [themselves], R’ Eliezer says: They have a presumption of taharah. R’ Yehoshua says: They have only the first day and the seventh day. R’ Akiva says: They have only the seventh day.