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George wrote:
> His first problem raises, from me ... in the traditions of
> this list, a minor pedantic quibble.

Peter wrote:
> For all practical purposes the sun 'hangs in the sky' at LAN.  We all agree
> about this.

Not really, it seems. In my newbie days I raised the question about how far
wrong one could go latitude wise with a close LAN time approximation given
30d to 60d elevation of the Sun and a full range of declinations.

Going way back in the archives, I questioned the importance of 10 or 15
seconds time in determining latitude at LAN in mid latitudes with Sun
elevations from 30d to 60d. A certain "pedantic" list member that will go
unnamed seemed determined to prove me wrong so changed the parameters to
worst-case scenario at almost 90d Sun elevation.

To quote said member on another issue much later: "To a scientist, as I am,
intellectual honesty is at least as precious, if not more so, than pecuniary
honesty. If that is to be called in question, then evidence is required. I
challenge Dan, and anyone else on this list, (other than Peter Fogg) to
identify a single posting of mine that shows any lack of intellectual
honesty. Perhaps that wasn't what Dan intended to imply, but it reads that
way."

I won't quibble about terms like "intellectual honesty." Instead I'll quote
a lawyer/politician acquaintance who told me, "If you don't like the
question being asked, answer another question of your own choosing." Please
tell me the proper phrase for changing the stated parameters of a problem to
settle the other fellow's hash (for our international readers, George, an
expression roughly meaning, "Win by any means") for no apparent gain or
purpose.

> Rather than just take one random sight and accept its unknown errors (in this
> case, apparently amounting to 1.2' ), we can take as many sights as possible
> over a few minutes on either side of LAN. Then graph them; altitude on the
> vertical axis, time on the horizontal.  Then compare the pattern of those
> sights with a horizontal line, disregarding any that clearly don't match the
> others (outlier = gross error), and thinking hard about the others, while
> bearing in mind those closest to the instant of LAN will least reflect any
> change in altitude.  An intuitive process.

We are on the same page page regarding graphing (and fitting Hc slopes to
observations), and always have been IMHO. I'm just not clear what you mean
by a "horizontal line" near LAN. The graph surrounding LAN by a few minutes
should look more like a camel's hump as I see it. VERY close to LAN, a
horizontal line, but as our pedantic friend would point out the time limits
will be dependent on latitude and declination. North Pole, late June, take a
coffee break between sights.  No big deal ;-)

Bill


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