[Avodah] Length of Archeological Ammah

[Zev Sero]

Micha Berger wrote:

> All in all, you see the basic pattern... R' Chaim Na'eh's ammah is
> slightly above the archeological range, but possibly within the margin
> of error. The CI's shiurim are well beyond the evidence.

Which conforms with the fact that he assumed the Rambam's dirhams
were the same as the Ottoman dirham in use in EY in his time.
Which in turn conformed with the minhag of Y'm Sefardim in his time.
But in fact the Egyptian dirham was slightly smaller, which puts all
of his calculations slightly over.  The Ottoman dirham weighed 3.205 g,
but the Rambam's dirham was probably more like 2.85g.  R Chaim Palache
wrote that the dirham of his day weighed 72 grains of barley, whereas
the Rambam wrote that it was 64 grains, and in PHM he wrote 61, which
is also what the Bartenura wrote.  RCP assumed that barley had shrunk
between the Rambam's day and his, but in fact it's the dirham that grew.

Taking a dirham of 64/72 of 3.205 g, or 2.85 g, yields a revi'is of
77 ml, and therefore an etzba of 1.924 cm and an amah of 46.176 cm.
If we take the dirham to be 61/72 of the Ottoman one, or 2.71 g, we
get a revi'is of 73.3 ml, an etzba of 1.893 cm, and an amah of 45.443 cm.

This still doesn't get us down to 43.5, let alone 42.8.   43.5 means
an etzba of 1.8125, a revi'is of 64.3 ml, and a dirham of 2.38 g.
42.8 means 1.783, 61.25, and 2.27.   That seems unrealistically small.

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Zev Sero                      The trouble with socialism is that you
zev at sero.name                 eventually run out of other people’s money
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