QUESTION: The Gemara quotes the Tosefta (Taharos 2:3) that states that when one has specific intent to use snow as a liquid, it can become Tamei like all other liquids. Unlike other liquids, however, if that snow is touched by something Tamei, the surrounding snow does not become Tamei. RASHI (DH Lo Nitma) explains that a mass of snow is not considered to be connected; each piece of snow (or snowflake) is separate from the other pieces.
RAV HENOCH EIGISH Hy'd (in MARCHESHES 1:39:12) asks that even if the particles of snow are not connected to each other, the snow surrounding the piece of snow that one touched should become Tamei, because liquids always become a Rishon l'Tum'ah when touched by something Tamei. Even if the mass is not considered connected, the snowflakes that become Tamei are touching the snowflakes next to them. These surrounding snowflakes should become Tamei and become a Rishon l'Tum'ah, since the snow is considered a liquid. They should subsequently cause the snowflakes next to them to become Tamei as a Rishon l'Tum'ah, and so on, until the entire mass becomes Tamei.
This question is not problematic for those who maintain that less than a Revi'is of a liquid does not transfer Tum'ah. TOSFOS in Pesachim (14a DH, d'Ika), however, rules that even the smallest amount of liquid transfers Tum'ah. Why, then, does the Tosefta consider the surrounding snow Tahor?
(a) The VILNA GA'ON on the Tosefta mentions that the Tosefta refers to a Tevul Yom. A Tevul Yom who touches liquids does not make them a Rishon l'Tum'ah (see Parah 8:7), but rather a Sheni l'Tum'ah. The snow that was touched, therefore, is a Sheni l'Tum'ah and does not transfer Tum'ah to other snowflakes.
RAV SHLOMO YOSEF ZEVIN (in L'OR HA'HALACHAH, p. 198) and RAV SHMUEL ROZOVSKY (in SHI'UREI REB SHMUEL to Gitin 16a) have great difficulty with the Vilna Ga'on's answer. The Gemara says that a case in which a mass of snow becomes Tamei is where the snow was placed in the interior of a clay oven or vessel that is Tamei. According to the Vilna Ga'on, however, the Gemara should mention a much simpler case. Anyone who is Tamei, other than a Tevul Yom, who touches snow will make the entire mass Tamei, because the first snowflake becomes a Rishon l'Tum'ah and makes the neighboring snowflakes Tamei, and so on.
(b) RAV SHIMON SHKOP (in SHA'AREI YOSHER, end of 3:27) suggests a novel approach. Although snow is not considered to be contiguous according to Halachah, the point at which one snowflake touches the next is called "Maga Beis ha'Setarim (contact in a hidden place), because, physically, all of the snow is one large mass. Tum'ah is not transferred if the only contact occurs in a hidden place (such as the inside of a body or the inside of an object). Therefore, snow does not transfer Tum'ah through contact with other snow, and the only way in which a mass of snow can become Tamei is by being placed in the interior of a clay oven that is Tamei.
(c) Perhaps we may suggest that although even a minute amount of a liquid is Metamei another liquid (and a Revi'is is not necessary), nevertheless each particle of snow is considered to be even less than "a minute amount." That is, since the Halachah states that snow does not combine with the neighboring snow, there is no particle of any mass at all which can be considered a "whole" particle of snow such that touching one side of it will make the other side Tamei. Therefore, no snow can be Metamei the neighboring bit to make it a Rishon l'Tum'ah. (M. KORNFELD; ha'Ga'on Rav Moshe Shapiro shlit'a agreed that such an approach is plausible.)


OPINIONS: The Mishnah describes the anatomy of a woman and says, "The Chachamim gave a parable [to teach the anatomy] of the woman: [there is] the main room (Cheder), the corridor (Prozdor), and the attic (Aliyah)." The Gemara explains that these are the parts of the womb of a woman. "The main room is the innermost one (the uterus), the corridor is outside of that (the cervical canal), and the attic is built above both of them. There is an opening (Lul) between the attic and the corridor."
To which part of the body does the Aliyah refer, and what is the Lul that leads from it into the Prozdor?
(a) RASHI and TOSFOS explain that the Aliyah is located on the roof of the Prozdor (that is, it is only to one side of the cervical canal). Occasionally, blood comes into the Prozdor from the Aliyah, but its blood is not like the blood of Nidah. There are five different colors of Dam Nidah, and there is only one color of blood that flows from the Aliyah (TOSFOS DH v'Dam). There is an opening from the Aliyah through the roof of the Prozdor.
The CHASAM SOFER (YD 188) points out that it is very difficult to resolve this description with the actual anatomy. There is no attic of any sort next to the womb! Some answer that according to the explanation of Rashi and Tosfos, the Aliyah is not part of a normal woman's anatomy, but rather it is a hole that forms in some women due to illness, and through this hole blood enters from the bladder (or other organs) into the Prozdor.
(b) The RAMBAM (Perush ha'Mishnayos, and Hilchos Isurei Bi'ah 5:3) explains that the Aliyah refers to the uterine (fallopian) tubes that are attached to the top of the uterus from either side, which connect the ovaries to the uterus. As the Chasam Sofer points out, this explanation matches the actual anatomical structure much more accurately. The Rambam writes further that it is not common for blood to flow into the uterus from the uterine tubes, but it occasionally happens due to a wound or illness. Such blood is not Dam Nidah. It enters the Prozdor via the Lul, which is an opening between the Prozdor and the uterine tubes.
(According to the Rambam's explanation as well, it is not clear what, and where, this opening (Lul) is. The only natural opening in the uterine tubes appears at the head of the uterus where the uterine tubes connect to the uterus, but this is far from the Prozdor (the cervical canal, which is at the other end of the uterus)! It seems, therefore, that even according to the Rambam, the Lul is a hole that is formed due to illness.)
However, the Rambam's explanation is very difficult to understand for the following reasons:
1. The Gemara says that the blood of the floor of the Prozdor is Metamei more than that of the ceiling of the Prozdor, since the Lul opens into the ceiling of the Prozdor from the Aliyah above it. According to the Rambam, the Aliyah refers to the uterine tubes on both sides of the Prozdor, and, therefore, it is open to both of them. Why, then, should there be a difference between the "ceiling" and the "floor" of the Prozdor?
2. The Gemara says that blood found from the Lul outward is more likely to be Tahor than blood found from the Lul inward. According to the Rambam, however, who says that the Lul is open to both sides of the Prozdor (since there is an Aliyah on each side), how can blood found from the Lul outward be more Tahor than blood found from the Lul inward? All of the blood of the woman passes from the Lul (or one of the Lulim) outwards when it exits, whether it comes from the Aliyah or from the uterus! The blood there should be no better than a Safek.
Perhaps we may answer these questions as follows.
1. The "Gag" (ceiling) of the Prozdor actually refers to the upper part of the Prozdor itself, beyond the Lul and closer to the uterus. The Rambam maintains that this part of the Prozdor is Metamei more than the floor -- that is, the part of the Prozdor below the Lul -- which is more Tahor. (This is the opposite of the explanation of most Rishonim, who explain that the ceiling is more Tahor than the floor.)
2. According to the Rambam, the reason why blood found from the Lul and outward is Tahor is that when blood (Dam Nidah) comes from the uterus, it flows out together (or one drop comes out before the rest, but it remains close to the uterus, as Rashi explains on 2b, DH ha'Gas). When only a drop of blood is found outside of the Lul, one may assume that it is from the Lul and not from the Dam Nidah of the uterus. (M. KORNFELD)