Negaim, Chapter 11, Mishnah 10. This chapter is devoted to nigei begadim, the negaim that appear in garments and in the raw materials from which garments are made. Our mishnah is full of technical vocabulary, first from the world of spinning and then from the world of weaving, and once the tools are pictured clearly the halachos fall neatly into place.
Let us take the mishnah clause by clause. "Hamaleh min hapokas l'chaveirto": one who winds thread off one bobbin onto a second bobbin. "Min hasalil l'chaveiro": or off one salil onto a second salil. "Min hakoveid ha'elyonah": or from the loom's upper bar, "l'koveid hatachtonah", down to its lower bar. And so too "shnei dapei chaluk", the pair of panels that make up a cloak. In every one of these, "shenir'eh nega b'echad meihen": should a nega appear on one of the two, then "harei hasheini tahor", its partner keeps its taharah. The mishnah then turns to two items that do contract tumah: "b'nefesh hamaseches uv'shessi ha'omeid, harei eilu mitam'im", the nefesh of the maseches and the standing warp are susceptible. Rebbi Shimon qualifies the second of these: as for the shessi, "im hayah ratzuf, mitamei", it is susceptible only when the strands were packed tight.
It is worth noticing how the mishnah is put together. Four separate scenarios are set out one after the next, and the halachah comes only at the close of the list: "shenir'eh nega b'echad meihen", when a nega shows itself on one member of a pair, then "harei hasheini tahor", its partner keeps its taharah. That one ruling is meant to be read back into each of the four scenarios individually.
Filling one bobbin from another
"Hamaleh min hapokas l'chaveirto": the pokas, as we have in this chapter, is the bobbin of the spinning wheel, the wooden piece onto which the spun thread is wound. The Rav explains the picture: two women are in business together, each holding her own bobbin, one with a cubit of thread wound on it and one with two cubits, and they wish to combine their thread onto a single large bobbin for storage. They tie a thread from the one to the other and turn, transferring the thread from bobbin to bobbin, so that at that moment a single thread runs between the two. If a nega now appears on one bobbin, the thread wound on the second bobbin is not tomei.
Filling one salil from another
"Min hasalil l'chaveiro": the salil seems to belong to a somewhat later stage, the stage of selling the merchandise. The Tiferes Yisroel describes it as a thin reed with a small piece of wood fixed at either end, the one set upright and the other set at right angles to the reed, so that the whole implement is designed to be turned. Apparently customers in those days would bring their own salil to the shop, and the sellers would wind onto it as much wool as the buyer wanted.
Here too the wool is being wound from one salil onto another, so a thread joins the two. If a nega the size of a gris appears on the wool of one salil and not on the other, whether the one bearing the nega is the salil giving over the wool or the salil receiving it, only that salil's wool is tomei and the other remains tahor. The thread stretched between them is not considered a genuine connection.
From the upper loom bar to the lower
Here too wool is passing from one salil to the next, so that while the winding goes on a single strand bridges the two. Should a nega the size of a gris turn up in the wool of one salil while the wool of the other is clear, it makes no difference which salil is giving over the wool and which is taking it in: the tumah stays with the wool that carries the nega, and its partner keeps its taharah. The strand stretched between them does not count as a true halachic joining.
Two panels of a cloak
The next case is a chaluk, a type of cloak built out of two panels. On the plain reading each panel is a piece of cloth in its own right, and the wearer fastens panel to panel with a knot over either shoulder, so that nothing links them beyond a knot that will later be undone. The Tiferes Yisroel offers a second picture: along the line where the panels meet the weaver laid in warp threads alone and left out the weft, leaving a strip that could be slit open with ease, so that the owner could widen the neck opening to whatever size suited him without ruining the garment. On either picture the two panels never became one, and so a nega on one of them leaves the other tahor.
Nefesh hamaseches: the soul of the web
Now to "nefesh hamaseches", the nefesh, meaning the soul, of the maseches. Maseches refers to shessi and erev together, warp and weft as they are being brought into one on the upright loom. Why should the weft be called a soul? The Rav teaches that the erev thread which is drawn in among the warp threads does for the cloth what a soul does inside a body: it is what brings the garment to life, turning bare strands into fabric. And the Rav adds a vital qualification: for as long as those opening weft threads have not settled securely into position alongside the portion already woven, their status remains that of shessi.
This calls for a second look, since the chapter has already established that a garment's warp and its weft are two distinct items, so that a nega found on one leaves the other tahor. Here, though, we are dealing with the garment at its earliest and crudest moment, before it has become anything at all: the warp still hangs slack and the weft is merely drawn through it without being fixed. At such a stage the weft has no standing of its own and is reckoned along with the warp, and so, as the Rav concludes, the two are added together in measuring whether a nega of a gris is present.
The Rav supplies a second way of reading the clause: it speaks of the opening moment of the weaving, when the weaver has drawn in his first pair of weft threads and anchored them. The expression for this act, shtei botei nirin, is one we meet among the melachos of Shabbos in the discussion of oreg: those two initial weft threads are passed through the upright warp and then set so that they cannot slip back out, and performing this is termed oseh shtei botei nirin. Our mishnah, on this understanding, is describing the garment before any third weft thread has gone in, and up to that point the weft carries the din of shessi. On this the Tosfos Yom Tov comments that the words "gimmel al gimmel", which ordinarily denote a measure of three fingerbreadths by three, have no bearing here whatever; what is meant is simply that the weaver has not yet put in his third thread.
The standing warp
"Uv'shessi ha'omeid": according to the Rav, this speaks of the warp as it stands stretched from the loom's upper bar down to the lower one, set in place for weaving and waiting for the weft to be drawn through. One might have supposed that since each strand stands on its own and no single strand is as wide as a gris, there is nothing here in which a nega could be measured at all. The mishnah teaches the opposite. Granted that the strands of the warp must be spaced apart, for without gaps the weft could never pass between them, and granted that they are not pressed together into one solid sheet; even so, "harei eilu mitam'im b'negoim", they do contract tumas negaim, because when the strands are taken in as a group a nega of a gris can be made out across them. (Our texts have the word "miyad" in this clause, and some raise the question of what it is doing here, as it seems not to fit.)
Rebbi Shimon disputes this. He maintains that a standing warp becomes susceptible to tumah only "im hayah ratzuf", where the strands were pressed close, each one flush against the next, the way the planks of a ritzpah, a floor, lie tight against one another; warp that is not packed in that fashion, in his view, is not susceptible at all. The halachah is not in accordance with Rebbi Shimon. Even where the strands stand spaced apart, once one can see that taken as a whole they cover the area of a nega kigris, they are tomei b'negoim.