Kelim, Chapter Twelve, Mishnah Four
Today’s mishnah, as well as tomorrow’s, deals with the purity of various types of “nails.” When the Mishnah uses the word “nail” it does not refer only to building nails, but to various nail-like instruments used in a variety of ways.
1) A blood-letters nail is susceptible to impurity.
2) But [the nail] of a sundial is clean.
a) Rabbi Zadok says that it is susceptible to impurity.
3) A weaver’s nail is susceptible to impurity.
4) The chest of a grist-dealer:
a) Rabbi Zadok says: it is susceptible to impurity,
b) But the sages say that it is clean.
5) If its wagon was made of metal it is susceptible to impurity.
Section one: The word “nail” is used here, but we are probably talking about a small scalpel. It is considered a vessel and therefore is susceptible to impurity.
Section two: Since the nail of a sundial is fixed in the stone that serves as its base, it counts as if it were attached to the ground, and things that are attached to the ground are not susceptible to impurity.
Section three: This “nail” is an instrument used to straighten out the thread on the loom. It is susceptible to impurity.
Section four: Albeck brings two interpretations of the “chest of a grist-dealer.” The first is that it refers to the chest itself. The second that it refers to the nail used to attach the chest to a wagon.
Rabbi Zadok and the sages debate whether this nail is susceptible to impurity.
Section five: If the wagon used to draw the chest is made of metal, then it (the wagon) is susceptible.