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Frank,

I agree with your statement regarding the meaning ascribed to "running
down the latitude" in 18th century navigation, and Slocum appears to
have been doing that to facilitate his landfall in Samoa.  And right in
this section we find the one clear, unambiguous documentation of a
lunar.

The reference to running down the latitude is in the middle of the
third paragraph that follows, the paragraph where he's bragging about
how well he knows the vagaries of the trade winds by reference to the
fact that he managed to run down the latitude without having to steer
much himself or light the binnacle.  I believe my interpretation with
which you disaggree is an easy conclusion from Slocum's text.  I
believe furthermore if you removed the blinders of your search for
evidence that Slocum only shot one lunar during his circumnavigation
you could see it too.  Slocum provides evidence that he shot only one
lunar, but that does not mean he shot only one.

"I sailed with a free wind day after day, marking the position of my
ship on the chart with considerable precision; but this was done by
intuition, I think, more than by slavish calculations. For one whole
month my vessel held her course true; I had not, the while, so much as
a light in the binnacle. The Southern Cross I saw every night abeam.
The sun every morning came up astern; every evening it went down ahead.
I wished for no other compass to guide me, for these were true. If I
doubted my reckoning after a long time at sea I verified it by reading
the clock aloft made by the Great Architect, and it was right.

There was no denying that the comical side of the strange life
appeared. I awoke, sometimes, to find the sun already shining into my
cabin. I heard water rushing by, with only a thin plank between me and
the depths, and I said, "How is this?" But it was all right; it was my
ship on her course, sailing as no other ship had ever sailed before in
the world. The rushing water along her side told me that she was
sailing at full speed. I knew that no human hand was at the helm; I
knew that all was well with "the hands" forward, and that there was no
mutiny on board.

The phenomena of ocean meteorology were interesting studies even here
in the trade-winds. I observed that about every seven days the wind
freshened and drew several points farther than usual from the direction
of the pole; that is, it went round from east-southeast to
south-southeast, while at the same time a heavy swell rolled up from
the southwest. All this indicated that gales were going on in the
anti-trades. The wind then hauled day after day as it moderated, till
it stood again at the normal point, east-southeast. This is more or
less the constant state of the winter trades in latitude 12? S., where
I "ran down the latitude" for weeks. The sun, we all know, is the
creator of the trade-winds and of the wind system over all the earth.
But ocean meteorology is, I think, the most fascinating of all. From
Juan Fernandez to the Marquesas I experienced six changes of these
great palpitations of sea-winds and of the sea itself, the effect of
far-off gales. To know the laws that govern the winds, and to know that
you know them, will give you an easy mind on your voyage round the
world; otherwise you may tremble at the appearance of every cloud. What
is true of this in the trade-winds is much more so in the variables,
where changes run more to extremes."

On Dec 15, 2003, at 8:53 PM, Frank Reed wrote:

> Fred Hebard wrote:

> And:
> "When he mentions running down the latitude, he is bragging about his
> course not varying much even though he did not steer by the compass,
> since..." etc.
>
> Wow. That's interesting. How did you come to that conclusion?? It
> certainly doesn't match what I've read of 19th century (and earlier)
> navigation. Running down the latitude was a well-established technique
> for ships that weren't certain of their longitude.

   

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