1)

(a)The size hide that one will be Chayav on Shabbos for tanning is one that is large enough to write a Kamei'a on it, and it follows - that one will be Chayav for carrying it the same Shi'ur.

(b)When Rava asked Rav Nachman what the Shi'ur will be for carrying un-tanned hide, he replied - that it is the same as tanned hide.

(c)And he extrapolated his answer from the Shiur of weaving and spinning threads on Shabbos - from the fact that the Shiur for weaving follows the Shiur for spinning (i.e. double the space between the extended fore and middle fingers). From this we see that the Shiur of a later Melachah sets the Shiur for an earlier one in the same process. In that case, the same will apply to carrying an un-tanned hide, whose Shiur will be the size on which one can write a Kamei'a (as we explained).

(d)The Shiur for a piece of hide that is not meant to be used for tanning is the same as one that one is.

2)

(a)The Shiur for carrying soaked dye is the amount that one would designate as a sample, and for un-sown seeds is a little less than a ki'G'rogeres according to the Tana Kama - and five seeds, according to Rebbi Yehudah ben Beseira.

(b)The Shi'ur for carrying sewage-water is a Revi'is, and for dyes to be soaked is the amount that one would use to dye a piece of cloth that one places inside a woman's head-covering (which is a larger Shiur than that of soaked dye). The Shi'ur for carrying ...

1. ... manure or fine sand is - enough to fertilize a stalk of cabbage, according to Rebbi Akiva (according to the Rabbanan it is sufficient to fertilize a leek).

2. ... cement (for which sewage-water is used), is large enough to place on the front of a furnace and punch a hole in it for the bellows to fan the flames.

(c)Usually, the Shiur for one Melachah is equivalent to the Shiur of the Melachah which determines its use (as we learned with regard to tanned and un-tanned hides). However, dye and seeds that have not been soaked and sewage-water, are different - inasmuch as a person will not take the trouble to soak such a small amount of dye, to carry out one seed to sow, or to mix just enough cement to place on the front of one furnace.

(d)To reconcile Rav Nachman with the Beraisa, which gives the Shiur for untreated hide as enough to cover a small weight - we establish the latter in the case of wet hide, and hide is not fit to be tanned until it has been dried.

(e)And as for the Mishnah in Keilim, which gives the Shiur for hide as five Tefachim by five Tefachim, and to which the Beraisa ascribes the equivalent Shiur for carrying on Shabbos - it is speaking about hide that has been treated in boiling water, making it sufficiently hard to sit on and use as a table.

3)

(a)We have just discussed the Shiur of untreated hide, known as 'Matzah'. There are two more categories of leather: 'Cheifah', which has been salted, and 'Dift'ra', which has also had flour added to it, but not 'Afeitzim' - gall-nuts (which would turn it into 'Klaf'). The Shiur for carrying ...

1. ... 'Cheifah' - is the amount on which one is able to write a Kamei'a.

2. ... 'Dift'ra' - is a piece sufficiently large for a Get to be written on it.

4)

(a)Parchment manufactured from a complete hide is called 'G'vil'. After the G'vil (the complete skin) has been spliced - the outer section is called 'Klaf', and the inner section, 'Duchsustus'.

(b)The Beraisa writes 'Klaf ve'Duchsustus, K'dei Lichtov Alav Mezuzah'. If taken literally, this means - that the Shi'ur for Klaf, as well as for Duchsustus, is large enough to write the two Parshiyos of Sh'ma and ve'Hayah im Shamo'a.

(c)This statement clashes with the Tana in our Mishnah, who gives the Shiur for carrying K'laf - as the smallest Parshah in the Tefilin (namely, that of 'Sh'ma').

(d)When we initially answer 'Mai Mezuzah, Mezuzah she'bi'Tefilin', we mean to say - that, by Mezuzah, the Beraisa is referring, not to a conventional Mezuzah, but to one of the Parshiyos in the Tefilin (the smallest one), which it refers to as 'Mezuzah'.

5)

(a)The Tana Kama of the Beraisa renders a person Tamei if he touches the Ketzitzah (the box) of the Tefilin or even the straps, provided they are attached to the Ketzitzah. According to Rebbi Shimon ben Yehudah however, Rebbi Shimon renders the Ketzitzah Tamei, but not the Tefilin-straps.

(b)Rebbi Zakai quotes Rebbi Shimon as saying 'Tahor Ad she'Yiga bi'Mezuzah Atzmah' - meaning, the actual Parshiyos (otherwise, not even the Ketzitzah will render him Tamei), a proof that the Tana sometimes refers to Tefilin as Mezuzah.

(c)We just answered the current Kashya (the clash between the Beraisa, which says 'Klaf ve'Duchsustus, K'dei Lichtov Alav Mezuzah' and our Mishnah), by explaining 'Mezuzah' in the Beraisa to mean 'Mezuzah she'bi'Tefilin. We refute this however, on the basis of the Seifa, which continues 'Klaf, Kedei Lichtov Alav Parshah Ketanah she'bi'Tefilin', implying that the Reisha is not talking about Tefilin, but Mezuzah (literally).

(d)We therefore merge the Reisha of the Beraisa with the Seifa (at one and the same time answering the Kashya) to read - 'Klaf ve'Duchsustus, Shi'uran be'Kamah? Duchsustus, Kedei Lichtov Alav Mezuzah; Klaf, Kedei Lichtov Alav Parshah Ketanah she'bi'Tefilin'.

6)

(a)We initially understand Rav's statement 'Duchsustus, Harei Hu ki'Klaf' to mean that - just as one may write Tefilin on Klaf, so too, may one write them on Duchsustus.

(b)Since the Mishnah writes 'Klaf Kedei Lichtov ... Parshah Ketanah she'bi'Tefilin, she'Hi Shema Yisrael', we can infer that this is not the Shiur for Duchsustus - implying that Duchsustus is not Kasher for Tefilin, only for Mezuzos.

(c)We answer that - although Tefilin may be written on Duchsustus, Lechatchilah, they should be written on Klaf. Consequently, one does not tend to designate Duchsustus for the writing of Tefilin.

7)

(a)'Halachah le'Moshe mi'Sinai' both Tefilin and Mezuzah are written on the part which is spliced - Tefilin on the under-side of the Klaf (the side nearest to the flesh), and Mezuzah on the upper-side of the Duchsustus (the side nearest the hair).

(b)We just learned that Tefilin are Kasher if they are written on Duchsustus. Mezuzos written on Klaf are - Pasul.

(c)And when the Beraisa states 'Shinah ba'Zeh u'va'Zeh, Pasul' - the Tana means that whether he wrote a Mezuzah on Klaf (even) on the side of the hair or on Duchsustus, on the side of the flesh, it is Pasul. (See also Tosfos, DH 'Idi ve'Idi'.)

(d)Alternatively, 'Shinah ba'Zeh u'Vazeh' is a Machlokes Tana'im in a Beraisa, and Rav holds like Rebbi Acha - who says 'Shinah ba'Zeh u'va'Zeh, Kasher'. The Beraisa speaks by Tefilin, and Rebbi Acha validates the Tefilin even if he wrote them on Duchsustus.

8)

(a)We then suggest that Rav holds like Tana de'Bei Menasheh, who says 'Kasvah Al ha'Gevil ve'Al ha'Klaf ve'Al ha'Duchsustus, Kesheirah'. What leads us to believe that Tana de'Bei Menasheh is speaking about Tefilin and not Mezuzah - because a Mezuzah that is written on Klaf is Pasul.

(b)We reject this suggestion however, on the grounds that we are no better off establishing the Beraisa by Tefilin - since Tana de'Bei Menasheh also validates G'vil, and Tefilin that are written on G'vil are Pasul.

(c)Consequently, Tana de'Bei Menasheh must be referring to - a Seifer-Torah.

9)

(a)We attempt to prove Rav's opinion from the Beraisa 'Tefilin she'Balu ... Ein Osin Meihen Mezuzah, L'fi she'Ein Moridin ... ' - because according to the Beraisa, the only reason that one cannot use the Parshiyos of worn-out Tefilin for a Mezuzah, is because of the prohibition of using something that is more holy for a less holy purpose. Otherwise, it is clear from the Beraisa, that it would be permitted. Now the Tefilin can only have been written on Duchsustus (otherwise, bearing in mind that we currently hold that a Mezuzah cannot be written on Klaf, how could one possibly use them for a Mezuzah (a proof for Rav's initial statement that Tefilin are Kasher on Duchsustus).

(b)We refute this proof too however, by establishing the Beraisa like Rebbi Shimon ben Elazar quoting Rebbi Meir - who used to write Mezuzos on K'laf, in that case, the Tana is talking about Tefilin that are written on K'laf.

(c)Rebbi Meir prefers a Mezuzah to be written on Klaf - because they then last longer.

10)

(a)In light of what we just explained, we now amend Rav's statement 'Duchsustus, Harei Hu ki'Klaf' to read - 'Klaf, Harei Hu ke'Duchsustus'.

(b)He is coming to teach us - that a Mezuzah that is written on Klaf is Kasher (see Tosfos DH 'Hashta de'Asis le'Hachi').

(c)On the other hand, he holds that Tefilin that are written on Duchsustus are Pasul.