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    Re: Backing & Hauling in Slocum
    From: George Huxtable
    Date: 2003 Dec 17, 17:15 +0000

    Bill Noyce wrote-
    
    >> I was interested in the use of "drew" and "hauled" to describe the
    >> change in wind direction in this passage (in the southern hemisphere).
    >>
    >> > 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.
    >>
    >> Seems like we were debating the terms used in this situation a while ago,
    >> though I don't remember whether we reached a conclusion.  Slocum seems to
    >> feel "drew" needs explanation, while "hauled" is treated as self-evident,
    >> though perhaps it's just obvious that it's the reverse of the prior motion.
    
    And Herbert Prinz replied-
    
    >No, Bill. The wind "draws" simply means that it fills the sails. The change of
    >direction that is opposite to "haul" is expressed by "farther [...] from the
    >direction of the pole".
    
    From George-
    
    I think it's less simple than Herbert makes out. I will quote below two
    mailings from earlier this year on a related thread, "Veering and backing"
    
    From me on 4 March-
    
    ===========================
    
    >Veering and backing, again.
    >
    >A thread arose, then fizzled out, some weeks ago about the meaning of the
    >terms veering and backing of the wind, particularly as to how these terms
    >apply in the Southern hemisphere. I was away at the time, but have done a
    >bit of book-study since. I no longer have records of that correspondence,
    >so can't recall the precise title of that thread, nor much about the
    >postings. So if I repeat here what others have said, I'm sorry.
    >
    >Anyway, here's my ha'porth.
    >
    >American readers will no doubt regard what Bowditch says as gospel. On
    >page 906 of vol 1 (1977), in the section on tropical cyclones, is the
    >statement-
    >
    >"Within the cyclonic circulation, a VEERING wind (one changing direction
    >to the right in the Northern Hemisphere and to the left in the Southern
    >Hemisphere) indicates the vessel is probably in the dangerous semicircle,
    >and a BACKING wind (one changing direction opposite to a veering wind)
    >indicates the vessel is probably in the navigable semicircle."
    >
    >Here, we are not considering Bowditch's impeccable advice about storm
    >tactics, just his definition of veering and backing.
    >
    >Bowditch is supported, to some extent, by the usually-dependable Peter
    >Kemp (ed) in the Oxford Companion to ships and the sea.
    >
    >Kemp states- "The wind is said to back when it changes contrary from its
    >normal pattern. In the northern hemisphere, north of the trade wind belt,
    >the wind usually changes clockwise- from north through east, south, and
    >west. When the change is anticlockwise, the wind is backing. In the
    >southern hemisphere, the reverse is the general pattern of the winds. When
    >the wind backs in either hemisphere it is generally taken as a sign that
    >it will freshen."
    >
    >About backing, Bowditch and Kemp agree. But a question arises about what
    >Kemp thinks of as the "normal" pattern of the winds. When a depression
    >passes westward across the norther hemisphere, mariners to the north of
    >its track will see the wind direction changing in an anticlockwise
    >direction, those south of its track will see the reverse. At least, that's
    >what my own thumbnail sketches suggest. There could be just as many
    >mariners in each category. So why should Kemp say that in the northern
    >hemisphere "the wind usually changes clockwise". It seems against
    >commonsense, and contrary to my own experience at sea. Can others comment?
    >
    >However, Kemp defines "veer" as- "The operation of the wind when it
    >changes direction in a clockwise direction. A wind which veers is
    >frequently a sign of settled weather in the northern hemisphere, of
    >unsettled weather in the southern.". It's clear from that last sentence
    >that he really does expect veer to mean a clockwise change, worldwide. In
    >that respect it is NOT the converse of his definition for "back" (which
    >seems odd), and is quite contrary to Bowditch.
    >
    >It's all rather unsatisfactory. How would the "Bowditch definition" work
    >out in practice? Remember that in a broad band around the equator,
    >Coriolis forces are negligible anyway, so this business about the law of
    >storms just doesn't apply. Is the Bowditch definition of "veer" intended
    >to suddenly reverse as the equator is crossed? Put yourself in the
    >position of a watch-officer in low latitudes having to report a 2-point
    >change in the wind direction to the old-man. Would you have to think-out
    >which side of the equator you happened to be before you reported it as a
    >veering or a backing? And would the old-man need to agree about which
    >hemisphere, and which definition, before he understood? It seems a crazy
    >arrangement that would not stand up at sea: not in a windship, anyway.
    >Perhaps the Bowditch definition is by, and for, meteorologists.
    >
    >I will cite another authority who disagrees with Bowditch completely (in
    >respect of Southern waters). In "A Glossary of Sea Terms" (Cassell, 1954),
    >Gershom Bradford is quite specific. He states- "The wind backs when it
    >changes against the hands of a watch, but veers if it changes with them.",
    >and "When the wind changes direction to the right with the hands of a
    >watch- for instance, from west to north, it is said to veer; otherwise, it
    >backs. This holds in both hemispheres, North and South."
    >
    >However, he goes on to complicate matters by adding- "If the wind is abeam
    >and changes forward, it is said to haul, and if it changes aft it veers.
    >It is, however, often spoken of as hauling aft." Here is a completly
    >different application of the word "veer", now with respect to the
    >direction of the ship's bow. According to modern usage these words haul
    >and veer would correspond to today's heading and lifting of the wind.
    >Harland , in "Seamanship in the Age of Sail", refers (only) to this
    >understanding of "veer".
    >
    >In an attempt to get a definitive answer (in terms of 18th century
    >practice) I have examined the Beaglehole edition of Cook's journal of his
    >first circumnavigation (1768 - 1770) in Endeavour, skimming through for
    >references to backing and veering. Most of that voyage was in Southern
    >latitudes.
    >
    >I have not found a single mention by Cook of "backing" of the wind.
    >However, he used "veering" 13 times, all when he was well into the
    >Southern hemisphere. In 2 of those references, it wasn't possible to be
    >sure, from the context, whether this corresponded to a clockwise or
    >anticlockwise change in the wind direction. On 7 occasions this was
    >clearly an anticlockwise change, and on 4 it was clearly clockwise. It
    >appears that Cook took the word "veer" to imply no more than a change in
    >wind direction, and didn't care which way the change occurred.
    >
    >Anothr word Cook occasionally used for changes in the wind direction was
    >"shifting", but I haven't been able to conclude whether this corresponded
    >to a particular direction of change.
    >
    >After all that, my conclusion, about the use of "backing" and "veering" in
    >the Southern hemisphere, is that there is no conclusion to be drawn. The
    >words can take either meaning. At least, in Northern waters, there's no
    >disagreement about their usage.
    >
    >George Huxtable.
    
    ============================
    
    and from Dan Allen on 12th March.
    
    > From John Harland's "Seamanship in the age of Sail" (Naval Institute
    >Press: 1985) -- an excellent summary of how ships were sailed from
    >1600-1860 -- he has written on page 12:
    >
    >Veering, hauling and backing of the wind.
    >
    >When the wind shifts around, so as to come from further aft, the modern
    >convention is to say it has 'veered'.  An older alternative was to say
    >the wind 'larges'.  If the wind draws forward, 'scants' as the
    >old-timers put it, it is said to 'haul'.  Thus the wind 'hauls
    >forward', but 'veers aft'.  I do not know how ancient this rule is, but
    >I have seenit as far back as 1878 (Uggla).  To find the principle
    >violated, the wind 'hauling aft' is not unusual in the old accounts,
    >some preferring 'draw aft', and 'haul forward'.  Along the same lines,
    >convention has it that the wind 'veers' when it shifts to the right or
    >clockwise, as one looks at the horizon, or with the sun.
    >Counter-clockwise movement is called 'backing'.  This is another area
    >where some confusion exists, some authorities considering 'haul' as
    >synonymous with 'veer' in this particular context.  Furthermore the
    >idea underlying 'backing' is that the wind is moving contrary to the
    >usual pattern of wind shifts, which in the Northern Hemisphere is
    >clockwise.  The exact opposite, however, is true in southern latitudes.
    >(Kemp; de Kerchove).  A wind which kept changing direction was said to
    >'chop about', and Uggla says that a wind which had shifted about was
    >said to have 'checked around'.  In Danish, there were different words
    >for a sudden marked change, vinden springer, 'the wind jumps', and a
    >gradual change, vinden skager sig, 'the wind checks [itself]'.  The
    >Elizabethan expression 'spring a-loof', meaning to turn abruptly to
    >windward is using 'spring' in this sense.  Skage literally means
    >'shake', but is closely connected with 'check' in its sea-sense.
    >
    >Dan
    
    ================================================================
    contact George Huxtable by email at george---.u-net.com, by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    ================================================================
    
    
    

       
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