Volume 53 Number 69
                    Produced: Wed Jan 10  5:00:06 EST 2007

Subjects Discussed In This Issue: 

Exotic Shofars
         [Natan Slifkin]
Question re Zemanim/Shiurim
         [Shmuel Himelstein]
Rabbeinu Tam and Geonic time for nightfall and Shabbos (3)
         [Menashe Elyashiv, Mechy Frankel, David E Cohen]
Yefas To'ar (and vegetarianism)
         [Chana Luntz]


From: Natan Slifkin <zoorabbi@...>
Date: Tue, 09 Jan 2007 19:35:28 +0200
Subject: Exotic Shofars

Those people currently doing Daf Yomi, and others, may be interested in
an article that I just wrote on the halachos of exotic shofars, which
also sheds light on various discussions in Maseches Rosh HaShanah. It
can be downloaded at http://www.zootorah.com/essays/essays.html (please
note that this is a revised version of the one that was circulating last

Natan Slifkin


From: Shmuel Himelstein <himels@...>
Date: Tue, 09 Jan 2007 13:31:34 +0200
Subject: Question re Zemanim/Shiurim

Obviously, until relatively recently (the past few centuries), clocks
did not exist. I'd be interested in knowing how our modern times for
Shkiah, etc., evolved, especially when there is a Yerushalayim Luach
which fixes Hanetz to the 1/4 minute.

By the same token, how did measures like an olive, an egg, a log
(liquid), etc. solidify into the exact Shiurim we have today?

Shmuel Himelstein


From: Menashe Elyashiv <elyashm@...>
Date: Wed, 10 Jan 2007 08:57:38 +0200 (IST)
Subject: Rabbeinu Tam and Geonic time for nightfall and Shabbos

Altho, Maran in his Shulhan Aruch holds by R. Tam, this has not the
custom in Israel. Many do hold as a humra, R. Tam time on Motzei
Shabbat, Yomtov & Kippur.

Another question is, what is candle lighting time? Starting from
Jerusalem super early 40 minutes, also Beitar, Elad, Emanuel & Petah
Tikva (btw, R.  O. Yosef holds that this humra is only for Ashkenazim),
30 minutes in Kiryat Sefer, 27 minutes in Haifa, and most places in
Israel 21-22.  Outside of Israel - 18 minutes.

From: Mechy Frankel <michaeljfrankel@...>
Date: Tue, 09 Jan 2007 21:03:32 -0500
Subject: Re: Rabbeinu Tam and Geonic time for nightfall and Shabbos

> From: Tom Buchler <tbuchler@...>
> Thanks for a very readable, comprehensive post which explains a lot!
> I am left with some issues. The most glaring issue is how did R' Moshe
> Feinstein get the 50 minute time and how does Silver Spring become six
> or seven minutes earlier? I calculated the time between Sunset (upper
> limb at the horizon at sea level) and various amounts of angular
> depression of the sun. The angles I used are 8.5deg (commonly used for
> end of Shabbes by Chabad, and determined by expert observation in the
> Negev), 12.6 deg (corresponding to 72 minutes after shkiah on the
> equinox in Ramerupt, France -- home of RT), and 16.1 deg, corresponding
> to 72 minutes after shkiah in Jerusalem on the equinox). I've include
> Key West as the southern-most point in the continental U.S. as a point
> of reference for R' Feinstein's "50 minutes for most places in the U.S."..
> If we assume the same angular depression produces 72 minutes in France
> as in New York, we get a time of 63 minutes in NY, not 50; and 61
> minutes in Silver Spring -- not a 6 or 7 minute difference between NY
> and MD. Am I using the wrong basis for performing this calculation? -Tom

I applaud this rather heroic attempt to reverse engineer R. Moshe's 50
minute p'saq.  Precision is always to be admired, but whether its also
accurate is a separate issue.

The short answer is yes.  You are probably using the "wrong" angle.  I
was not aware that Chabad used 8.5 deg though that is indeed a common
figure.  However I have seen figures ranging from a low of 5 deg
(equivalence in time), to ten degree (equivalent.).  these last two are
outliers, with the most common in Europe generally falling between
7.5-8.5 degrees - though see the M'lameid L'ho'il (R. Dovid T'zvi
Hoffman - the poseiq for Germany before WWI) - who specifies 7 deg.  For
what its worth, civil twilight - when the US Navy deems it dark enough
for stars to appear - is 6 deg below the horizon, while astronomical
twilight - when no refracted sunlight appears anywhere (which might
equivalence to the interpretation of 4 mil as designating complete
darkness) is -18 deg, though that's longer than 72 minutes most places.

There are also a number of other factors that might contribute to a
variation in calculated z'manim.  You have already noted height above
sea level as one issue.  Generally the delay in observed darkening will
vary as the square root of the observational height (this is simple
enough to calculate and its proof is left as an exercise for the
student.  If anyone has trouble we can run a recitation).  It is not a
settled halachic slam dunk (i.e. pos'qim have differed) how to deal with
this.  i.e. whether to correct z'manim back to sea level or leave them
as actually observed in a location, or some combination. E.g. a
correction (by imagining they are not there) for the "close in"
geographical features (mountain/valley) that might change observation
but accept the reality of more far off or long range features (a distant
mountain range, or a broad and high plateau.).

Perhaps another, and richer, source of calendrical variation/confusion
goes back to the thee bainoni stars whose appearance signaled night.  A
problem there is that rishonim have posqined (and picked up by shulchon
aruch and other acharomin) that we actually need to wait for three qoton
stars, which would of course appear later.  Indeed some would add the
further requirement that the 3 stars be contiguous.  However the actual
practice in many q'hillos was just to wait for the bainoni - not qoton -
stars.  But depending on what the initial assumptions are (bainonis,
qotons, contiguous/not), we can arrive - and different published luchos
did arrive - at a variety of times for motzoei shabbos in practice.
This could easily cover the variation between NY and the other Silver
Spring shuls, but I am no longer sure (actually i was never sure, it was
a conjecture on my part.  But Mr. Buchler has inspired me sufficiently
to estimate some of these numbers more accurately) they simply corrected
for latitude only, as I had speculated.

Now, I am also not suggesting that this is how R. Moshe arrived at his
50 minutes.  I have in fact no idea how he did the translation froma
european RTam, but the parameter space of variation cited above would, I
suspect, accommodate such a number.

As to the 6-9 minute variation from NY time in Silver Spring; I've gone
back and looked at the magnitude of some of these variations myself and
also conclude that - alone - the variation between NYC (per Google
earth, 40deg 51 min in the middle of my old hood -Washington Heights,
and Silver Spring at 39 deg 2 min will only buy a small fraction of the
6-9 minutes.  Sea level correction is more promising assuming NY is at
sea level.  Our location in Silver Spring is more than 300 ft above sea
level and this will buy a couple of minutes (more like two).
Incidentally, if my assumption that Washington Heights is highest point
in NYC is correct (more specifically the little park with the monuments
on Fort Washington Ave right opposite the back entrance to the 181st IND
entrance, where George Washington emplaced his guns to close off the
upper Hudson river and where i was able to extract a height of 294 ft
from GoogleEarth), then there should also be close to a two minute
difference in z'manim between WH vs R. Moshe's apartment on the lower
east side.  Needless to say, in practice there isn't.  But i digress.

As an aside, let me also put in a word for the halachic virtue of
eyeballing stars (and sunsets for that matter) as we used to do when i
was a kid, rather than running to calendars, which had a wide variety of
published z'manim in those far off days.  (my parents were
hungarian/romanian/transylvanian - marmorishe yidden - and that's what
we did, at least when the sky was clear.  so shoot me).  The published
tables and calendars, even when they rely on US naval tables - which i
assume most do - are still never "exact" in principle, because they
include an averaging assumption.  i.e. the degree of refraction and
scattering, which enables you to see sunlight even when it is no longer
within your line of sight, is dependent upon the state of the
atmosphere, which is a variable.  And that variation can amount to as
much as a couple of minutes.  Instead, the table calculations use a
single averaged atmosphere.  Eyeballing on the other hand, automatically
corrects for atmospheric variation and will give you truer, real time,
z'manim.  Also its more fun.  But alas, it doesn't seem to be in much
halachic favor these days.

Mechy Frankel

From: David E Cohen <ddcohen@...>
Date: Tue, 9 Jan 2007 19:03:54 +0200
Subject: RE: Rabbeinu Tam and Geonic time for nightfall and Shabbos

Tom Buchler posted a table of the time between sunset and various
angular depressions of the sun at various latitudes, and asked how R'
Moshe Feinstein came up with his figure of 50 minutes.

The table that was posted is valid, but only at the equinoxes, when the
amount of time after sunset until any given angular depression is at its
minimum.  At the summer solstice, when it is at its maximum, it takes 50
minutes, rather than 41 minutes, to reach 8.5 degrees in New York.

It is not just Chabad that uses 8.5 degrees, but most communities here
in Israel.  I believe that this figure was arrived at based on the
empirical observations of R' Yechiel Michel Tukechinsky.  In Jerusalem,
this ranges from 36 minutes at the equinoxes to 42 minutes at the summer

I suspect that perhaps R' Moshe was advocating the adoption of the "8.5
degrees" custom in the United States, but since the average shul luach
maker could not be expected to calculate angular depression of the sun,
he wanted to give a number of minutes that people could safely use
year-round, and he gave 50 minutes for New York since that is the
maximum amount of time that it takes there to reach 8.5 degrees.

When R' Moshe wrote that this was the correct implementation of the
position of Rabbeinu Tam for New York, it seems that he was clearly
referring to what Mechy Frankel described as the Minchas Kohein's
interpretation of Rabbeinu Tam. This means that we are more concerned
with empirical observation than with it corresponding to exactly 72
minutes at any particular latitude.



From: Chana Luntz <chana@...>
Date: Mon, 8 Jan 2007 11:39:24 -0000
Subject: Yefas To'ar (and vegetarianism)

Frank Silbermann <fs@...> writes:

> Obviously, not all slaves are required to convert (or there'd be no
> concept of "gentile slave").

Actually this is not true - see Shulchan Aruch Yoreh Deah 267 and my
post in Mail Jewish vol 29 no 70
http://www.ottmall.com/mj_ht_arch/v29/mj_v29i70.html#CSA where I set out
the relevant si'ifim in the Shulchan Aruch.

Bottom line a "gentile slave" or "eved Ca'anani" does indeed have to
convert.  And the master has 12 months to pursuade him to do so before
being required to sell him on.  The difference is that a slave converts
"l'shem avdus" [ie for the sake of slavery] and not l'shem cherus [for
the sake of freedom}.  If in fact the slave converts l'shem cherus then
he is automatically entitled to be free.

> What is the status of a female slave's children if she doesn't
> convert, but the master has children with her anyway?

As mentioned, it is clear in the Shulchan Aruch that full ownership does
not come into effect until conversion l'shem avdus.  Note by the way
that Shulchan Aruch Yoreh Deah siman 267 s'if 69 records a machlokus as
to, if the master has children with his female slave - ie assuming she
has indeed become a slave, what is the status of the children (some say
a slave, some say free).  Note this is something forbidden to him, the
Shulchan Aruch is dealing with the bidieved.  I think you may be
thinking about the female slave being married by the master to an eved
ivri (which is a whole different kettle of fish - but the concept of
eved ivri is, according to Shulchan Aruch Yoreh Deah siman 267 si'if 14
something that only applies when Yovel is noheg, ie not today). But
until she actually converts l'shem avdus, I can't see any reason why the
children would have any different status than if the master had had
relations with any non Jewish female. 

> Back to the original subject, how would the yafas to'ar convince the
> Bet Din that her prospective conversion is purely for the sake of
> Heaven, and not for the sake of marriage to a Jew????  (Or is this
> test not actually a halachic requirement?)

While I am not aware of us having a great deal of halacha on the yefas
to'ar, I would guess that it would follow the situation vis a vis an
eved c'nani, where you can see that the requirement to convert for the
sake of Heaven is somewhat attenuated.  It is rather, it would seem from
the sources, that unlike the case of a convert converting l'shem cherus,
pursuasion is allowed vis a vis the prospective eved - and the motives
for conversion are expected to be different to a convert converting
l'shem cherus.

> Of course, if the captured woman converts to Judaism of her own free
> will (with the alternative of going free), then we can no longer say
> that the law of Yefas To'ar is a special permission to do
> anything. Once she converts, how the soldier met her becomes
> irrelevant.  (Or is the whole point of Yefas To'ar that _this_ woman,
> unlike all other gentiles, _may_ convert for the sake of marriage
> rather than for the sake of Heaven?)

I think that is probably right - ie that the exception is that she is
allowed to convert specifically for the sake of marriage to the husband.
Other gentiles may be allowed to convert for the sake of avdus, but in
that case they are not allowed to marry their master (although may, in
the times of Yovel, marry an eved ivri of the master).



End of Volume 53 Issue 69