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Frank Reed, in message [10104], responded to a rather-odd posting [10103], 
from within the archive, from (presumably) geo589@exemail.com.au , replying 
to an earlier posting by a chap called Malcolm Misuraca, which was full of 
sound and fury.

That earlier posting, and that name, seemed completely unfamiliar, until Frank 
explained all by dredging down into the archive, and quoted a post, back from 
November 1997! That was well before Frank's time on this list or its earlier 
equivalent, and indeed, a year or two before I got involved. Dan Allen has 
participated throughout, and his name cropped up in those days too; Paul 
Hirose as well. Indeed it's thanks to Dan that the archive from those days 
has been preserved at all, though it appears to be somewhat incomplete from 
those early years.

Frank added- "Also, in case anyone new is curious, "Nml" was the original name 
for this discussion group (before "Navigation-L" which was before 
"NavList")."

However, I doubt whether that's the case. I see that "Nml" tag in archived 
postings from my own early days on the list, when it's name was certainly 
"Nav-l" and I remember no "Nml". I suspect that the tag "Nml" may relate more 
to where the list's doings have been archived, rather than to the name of the 
list itself. Dan should know.

Indeed, the Navlist archive seems to have chosen to subsume all of the Nav-l 
archives within itself. Nothing wrong with that, it's a sensible thing to do, 
but is there a way to tell which forum a particular posting went to? If not, 
there should be. Remember, for a (short) time, both lists existed in 
parallel, without cross-correspondence.

=============================

Enough about our archive, and now back to the subject of that old Misuraca 
posting, which I won't quote again, as Frank has done so in [10104], with 
this comment - "Note that this message by Mal Misuraca was clearly part of 
some more involved discussion, however we do not seem to have any of the 
other original messages from this one."

But we do. There were a few messages in the previous month October 1997, on 
that topic. Some were inconsequential or illogical, but the one that appears 
to have triggered Misuraca's outburst was on October 28, 1997, from Tony. I 
suspect that this was perhaps Tony Severdia, from San Francisco, a regular 
correspondent from those days, no longer with us. He and I used to enjoy 
occasionally crossing our pens, and, on other occasions, agreeing.

It's worth reading what he had to say, which brought about such a reaction from Misuraca.

Under the subject heading "fix with the noon shot", Tony wrote-

==============

"PULEEZE ...folks!

This same proposition (in many cases nicely thought out _in theory_) is 
proferred about every three months on this very list.

I offer for your learned consideration:

1. If a true "fix" were possible, it would be heralded in any and every 
navigation text you might have ever read.

1a. A fix by definition is the most accurate position that can be attained by 
the navigator by (in this case) celestial means.

1b. The sloppy navigator can, of course, obtain a _rough_ _estimate_ of 
longitudinal position by making many compromises. If he has not the slightest 
idea of his longitude, it is better than nothing (Chuck was on the mark here 
with lifeboat nav).

2. While theoretically possible, EVERYTHING near LAN dependson _absolute_ 
accuracy of the sextant altitude sight, time and related factors.  (delta 
declination, North/South, East/West sailing tracks are _only_ a very _minor_ 
part of the equation).

The best method is to bow to well proved practices of well time-spaced running 
fix ...then one can call it an "Rfix". (But, still certainly not as good as a 
true celestial fix).

Sorry to be so didactic, but the proposition keeps coming up as earlier 
mentioned ...with some folks proferring "a new revalation".

Everything depends on what measure of innacuracy _you_ are willing to accept.  
SURELY, NO ONE would accept such rough approximations in approaching atolls 
or landfall!

 A Navigator's well kept DR since last true fix is very probably much better.

Wasted words?  I hope not!  Bye.

Tony    San Francisco, CA
(Home of NAVIG94)

=====================

Tony's opening words in 1997, "This same proposition (in many cases nicely 
thought out _in theory_) is proferred about every three months on this very 
list." have proved only too true, ever since.

In spite of the recent support proffered by geo589@exemail.com.au , Misuraca's 
old posting comes across to me as long on polemics and rhetoric, but lacking 
in clarity of logic, as Jim Wilson has pointed out. I suspect, from a look 
into Google, that Misuraca is an American lawyer, which may explain 
something. And his subtitle, "Celestial in a day", may explain rather more. 
If his aim was to teach celestial IN A DAY, no wonder he went for short-cuts!

As a result, a generation of "navigators" may be going home, to say, "Ma, 
today we learned celestial navigation", and think themselves competent to 
sail around the World. But, it appears, with no concept of a position line, 
no familiarity with observing anything other than the Sun, and that only 
around noon, if it happens to show then for a sufficient interval. No concept 
of what a sine is, or a cosine, even though all the drudgery is now removed 
from using such things by the availability of calculators. And with only one 
method of determining longitude, a way that calls for exquisite precision of 
observation, repeated, to achieve a mediocre result. And throws away all the 
precision that a navigator's craft is able to deliver, when it's been taught, 
and learned, and applied properly.

The only thing that can be said in favour of such lazy teaching is that it's 
intellectually undemanding, because it involves no trig. If the aim is to 
give the appearance of learning, without the substance, then that fits in 
with the modern demand for instant gratification. Fair enough, if there's no 
pretence that this is real celestial navigation. I pity the serious student 
who has signed up for such a course, hoping to understand the real thing, and 
finds himself short-changed.

But there's little fun in arguing against such a view in the absence of its 
proponent, who has long since quitted our scene. However, this same argument 
is doomed to run and run, just as Tony predicted. Frank Reed has his own 
views, which differ greatly from my own, and listmembers are by now painfully 
familiar with both.

=========================

Mal Misuraca, 12 years ago, offered to copy pages from volume 3 of the 
Admiralty Manual of Navigation, 1958, on the topic, and geo589@exemail.com.au 
, thinking that to have been a recent posting, requested just that. I can't 
offer that edition, but I can supply a copy of the 1938 edition, where the 
moment of LAN is treated in great detail. That's mainly from the viewpoint of 
predicting the correct moment to observe for meridian altitude; for latitude, 
not longitude. It includes a table to ease calculation of the time interval 
between meridian passage and maximum altitude. However, it offers a section, 
starting on page 156, which I copy here. To preserve precision of such an 
equal-altitude observation, it sets very restrictive conditions on the 
separation of azimuth from due-South, and on altitude and declination of the 
Sun, which are far removed from the notion of longitude-around-noon that 
proponents of the method take for granted. Under those restrictions, the 
method can indeed be very precise, but it becomes 
longitude-nowhere-near-noon.

If anyone has a copy of the 1958 edition, it would be interesting to learn if it says any different.

George.

contact George Huxtable, at  george@hux.me.uk
or at +44 1865 820222 (from UK, 01865 820222)
or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
www.fer3.com/arc 


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