Gevil
Gevil or gewil () or () is animal hide made of whole parchment that has been prepared as a writing material in Jewish scribal documents, in particular a Sefer Torah (Torah scroll). According to most views of Jewish law, a "Sefer Torah" (Torah scroll) should be written on "gevil" parchment, as was done by Moses for the original Torah scroll he transcribed. Further, a reading of the earliest extant manuscripts of the Mishneh Torah indicate that "gevil" was halakha derived from Moses and thus required for Torah scrolls. Maimonides wrote that it is a law given to Moses at Sinai that  a Torah scroll must be written on either "gevil" or "klaf" in order to be valid, and that it is preferable that they be written on "gevil". Etymology. Related to , "gewil", a rolling (i.e. unhewn) stone, cf. , "to roll." Definition. "Gevil" is a form skin for "safrut" (halakhic writing) that is made of tanned, whole hide. The precise requirements for processing "gevil" are laid down by the Talmud, Geonim and Rishonim. According to Jewish law, the preparation of "gevil" must include salt, flour and "mey afatzim" (wasp residue/gall-nut water). These requirements were reconfirmed as a Law given to  Moses at Sinai by Maimonides, in his Mishneh Torah. Gall nuts—rich in tannic acid—are a tree's reaction to an invasive parasitic wasp's egg; the pure black tint of the ink used on Torahs results from the reaction between the tannic acid and iron sulfate (a powder used to make the ink). There are three forms of tanned skin known to Jewish law. The other two forms ("klaf" and "dukhsustus") result from splitting the hide into two layers; however, there is some dispute as to their identification. Others deviate from the traditional process and use modern chemical  processes instead. However, some believe that this invalidates the parchment for scribal use. According to the "Halakhot Gedolot", "klaf" is the inner layer, adjacent to the flesh, while "dukhsustos" is the outer layer, on which the hair grows: The same view is expressed in the oldest extant manuscripts and critical editions of Maimonides' Mishneh Torah and the Babylonian Talmud. This is also the same definition which appears in the minor Talmudic tractate called Sofrim. However, more recent authorities reverse the two descriptions, and many printed editions of the Mishneh Torah are "adjusted" to reflect this. The reason for this original  adjustment away from the original definition is a mystery. Some suspect that copying errors are to blame. As a result, many have become confused, in terms of which part of the skin should be used for writing. Using the full hide known as "gevil" for "Sifrei Torah" does avoid this issue, but unfortunately this solution won't work for "tefilin" which must be written on klaf and are not kosher if written on "gevil". Uses. According to the Talmud, Moses used "gevil" for the Torah scroll he placed into the Ark of the Covenant. Elsewhere in the Talmud, there is  testimony that Torah scrolls were written on "gevil". Today, a handful of Jewish scribes and artisans continue to make scroll material in this way. However, the majority of Torah scrolls are written on "klaf", in their belief that the Talmud recommends (as opposed to requires) "gevil" and relates to the optimal beautification of the scrolls rather than an essential halachic requirement. Given the uncertainty about which layer of the hide is in fact the "klaf", there is a growing movement for insisting on a return to "gevil" in Torah scrolls in order to avoid all doubts. Most of the Dead  Sea Scrolls (200 BCE), found in and around the caves of Qumran near the Dead Sea, are written on "gevil". Properly, "klaf" should be used for "tefillin" and "duchsustus" for "mezuzot". Once more, this rule is often relaxed in practice but there is a minority which seeks to return to the actual law.