Ship Maneuvers in Patrick O'Brian's Wine Dark Sea

Encounter at Cape Horn/Diego Ramirez

by C. F. Keller

Contents

Figures

NOTE: To follow this set of maneuvers it might be well to consult a fairly good map of the ocean around the southern tip of South America. The action takes place south of the southern-most island group in the region, Diego Ramirez (approximate coordinates: 56 30' S, 68 52' W). You will note that this group is well east of the western coast of South America.

Introduction

In this encounter, Surprise lies to awaiting for the predicted arrival of three American merchantmen, referred to as China ships. They arrive when the sea is shrouded in intermittant fog, making this an almost ethereal encounter. But the unreality of it is quickly shattered by the stern chaser of an unexpected brig and the broadside of a heavy American frigate. The events have three settings--(1) the relative orientation of the China ships, their American escort, and the Surprise, including initial maneuvers prior to the opening of the engagement, are described in Chart 1; (2) maneuvers during the engagement are described in Chart 2; and (3) Surprise sailing to and past a large iceberg and on east are described in Chart 1 again. All three are easy to visualize in general, but hard to understand in detail. In fact, at several times there seems no way to get around some inconsistency. Yet it's a pretty good, suspenseful tale, well told, and worth following. (All page citations are from the W. W. Norton paperback.)

1. The Encounter

This is complicated, because the wind direction changes from northerly, backing into the west to northwesterly. Since square-rigged ships can sail no closer than about 7 points from the wind, this puts stiff constraints on the maneuvers described, and there is an inconsistency in the timing of when the wind moves from north to northwest. There are three groupings: the three China ships (north and then increasingly west of Surprise) trying to get west enough to turn north into the Pacific; the American frigate and brig, who have obviously seen the Surprise and are moving to head it off from the west-a bit north, and the Surprise itself which is heading roughly NNE to get the weather gage of the China ships. As in the Indian Ocean description (HMS Surprise), POB pushes credibility to the limit. The following is the best compromise between wind, successive position, bearing.

Aubrey has intelligence that three U.S. "China" ships are to round Cape Horn by sailing south of the island group Diego Ramirez sometime around full moon. Surprise gets there early, rides out a storm, and the day after full moon in a general misty/fog sights two and then three merchantmen about three miles distant to the northeast on the larbord beam (point 0 on Chart 1). Visibility is intermittent through breaks in the fog. The wind is light and from the north (pp. 238).

The lead ship is observed south of the islands getting ready to change course "bringing the wind on to her quarter in order to sail westward round the southern shore of the last island in the group before hauling her wind and steering as near north into the Pacific as the breeze would allow." This is a perplexing statement for two reasons: (1) if the wind is from the north "bringing the wind on to her quarter" must mean that she will be sailing southwest, not west. (2) sailing north would not get the ships into the Pacific since the western edge of South America at that latitude is 76 W -- 8 degrees west of their location. However, if we allow southwest to be west and west-northwest to be north, then everything is fine. (As we shall see, the wind backs towards the west which must drive the merchantmen to a more southwesterly heading close-hauled! (Points 1 and 2, Chart 1)

Aubrey's plan (p. 239): "If the Surprise ran a little way to the east and then steered north she would have the weather-gage..." If the wind is from the north, sailing east would possible, but even close-hauled the farthest north she could head would only be a bit better than east north east. However, as the wind backs into the northwest, Surprise could head more northerly. Jack calls for a course north-north east (point 2, Chart 1) which means the wind must already have backed all the way to northwest!! Thus the China ships on the opposite tack must already be heading west-southwest. This presents a small problem because it is not until p. 240 that POB writes: "Fifteen minutes more, and as he had expected the breeze freshened, backing westward." The best I can make of this is shown in Chart 1.

Unlooked for Additional Ships

Two new ships are discovered through the fog on the "larboard beam" (i.e. a bit north of west), one larger than the other, but there is confusion since no one can tell how large they are. These new ships are said to be "between the Surprise and her quarry" (near point 3 Chart 1). We are also told (p. 241) "the two vessels were moving quite fast in relation to one another. (Here I suspect (from subsequent events) that the smaller of the two is racing towards the Surprise faster than the bigger ship?) Looking back at the China ships-"By this time the Surprise was perfectly well placed for her attack on the China ships. They were well beyond the islands moving steadily a little south of west and with the present breeze she (Surprise) could cross their wake under a moderate press of sail within an hour or so." Since Surprise must be sailing 4-6 knots, this is a long time, and so it must mean that Surprise will come about onto the same tack but be able to sail closer to the wind, thus angling north to cross the wake after an hour's sailing. In fact that is exactly what Aubrey does, coming about to a starboard tack probably a point or so north of WSW ( point 3 Chart 1).

Now some geometry. We need to work out how much the relative positions between Surprise and the China ships change in about 20 minutes if each is sailing about 6 knots. If originally 3 miles apart, 15 minutes would be required to close if heading directly toward each other. Actually, Surprise is heading NNE and China ships are heading WSW. Thus the closing component would be about 7 knots, which would be between 2 and 3 miles in 20 minutes. Thus very soon the relative positions would be east and west of each other with the two strange ships described as being in between. POB doesn't say which direction the strangers are sailing. Presumably they have spotted Surprise and are heading from the China ships towards it--i.e. sailing roughly east, perhaps a bit south (point 3 Chart 1). Jack assumes the two ships are heading west to Valparaiso or some such destination, which brings up the question of why he doesn't seem to be overly distubed that they are now heading rapidly east towards him. He knows this because he states that the Surprise "would probably pass within hail" (p. 241). Somewhat of a problem here.

2. The Engagement

Now things heat up. The brig appears (p. 242) "dim on the larboard beam". This statement and the one following : ....."her big fore-and-aft mainsail was hauled right aft, she heeled violently to leeward".... require some radical thinking. My best guess is the following. The brig's original approach is from the west (point 1 Chart 2), but when the Surprise tacks to WSW, it must adjust course quickly and in the fog at that. The above POB quote describes the brig as it passes the Surprise on her larboard side (point 2 Chart 2). Thus the brig must have come in heading east, then turned a bit north. This would have it pass the Surprise "heeled violently to leeward". This might also keep it from bringing its broadside to bear, allowing it only to fire a stern chaser once past: "her stern-chaser went off sending a ball through the Surprise's forestaysail and she vanished into the mist". Following this we are told nothing about the brig's maneuvers, but it surely must have come about to re-engage Surprise on the opposite side from the frigate.

The American frigate appears out of the fog, "a second dark form heaved up on the starboard bow" (p. 242). The American fires a broadside (point 3 Chart 2), missing because it fired on the downward role (this strains credibility unless the patchy fog is invoked). Surprise falls off from the wind (to the south) so that her starboard guns bear and returns the fire. But now Surprise is sailing a course parallel with the frigate directly under its more powerful guns (Chart 2). So in a desperate maneuver Aubrey tacks to starboard directly in front of the big American and fires a larboard broadside "at point blank range" (p. 243) before moving away in the opposite direction (point 4 Chart 2). For description of the brig's subsequent maneuvers see below. Note that I have changed the POB direction as they all sail off towards the iceberg from ENE to NNE, also discussed below. In the following discussion positions are again found on Chart 1.

3. The Chase past the Ice Mountain

Following its last broadside Surprise finishes tacking, and Jack orders a heading "ENE a half east" which I take to mean a half a point (6 degrees) east of ENE. The Americans give chase. The heavy frigate wears, making a wide turn first south and then east, and comes onto a parallel course with Surprise a bit to its lee. The brig presumably has turned back north and is following Surprise even more closely (see details below). Now POB makes a statement that simply cannot be true. He writes that the American frigate has turned later and so is about a mile behind and east of Surprise. This makes no sense. Surprise is heading just a bit north of east and going like smoke and oakum. How could the American frigate turn later yet end up even farther east? And, if he did, would he not simply come to a larboard tack (in NW wind this would be NNE) and cut Surprise off? No, he must be about a mile behind and a bit south. But even then the problem persists for both ships are attempting to get around a two mile long ice island to the north. Jack could easily do it by sailing not ENE, but NNE. He doesn't do this presumably because of his proximity to Diego Ramirez islands and his desire to sail as fast as possible to get away from the brig. Even so, the American can easily get north of the ice island by sailing NNE. He apparently doesn't do this because he is trying to catch Surprise before it gets around the ice island. But it won't wash since further on (p. 246) POB makes another statement that can't be true. He has Jack say that the American won't get around the iceberg until he has tacked two times. The geometry imposed by an ENE course in a NW wind makes it clear that the American can get by the iceberg easily by sailing close-hauled NNE. And so we have a major problem.

I propose a radical solution, one that easily matches POB's descriptions of all the events--namely, that the paperback (and perhaps the hardcover) has a typo--that the course Jack calls for in not ENE, but NNE (point 4 Chart 1)! This allows the iceberg to be well north of the ships drifting ever closer to the islands, and Surprise must sail as close-hauled as possible to head it. This course also keeps Surprise to windward of the frigate, and it allows, as POB writes, the frigate to be east of Surprise (point 5 Chart 1). Finally, the frigate's course is such that it cannot get around the iceberg without tacking as Jack says it must. Thus all's well with the change of a single letter--E to N.

What's the brig been up to?

When we last saw the brig, it was disappearing into the fog astern of the SWS-heading Surprise (point 2 Chart 2). POB doesn't mention it again until the Surprise is racing north towards the iceberg (p. 244) "'Sir', said Wilkins, 'the brig has altered course.' Certainly: Jack had expected it. These turns and her own manoeuvres had brought the brig to the westward of both ships on Surprise's quarter and somewhat nearer to her than the heavy frigate; and for the last two miles she had been losing steadily." And so we are left to sail the brig to that position as if we were its captain. In Chart 2 I give my rendition in a dashed line. In doing so, I assume that, with its big fore-and-aft sail, it can come closer to the wind than the square-rigged ships. I have it pass Surprise to east, come about to get south and attempt to pass Surprise again to deliver a broadside. But then the brig realizes that Surprise has taken unorthodox measures and tacked right in front of the frigate (point 4 Chart 2). This calls for a potentially dangerous maneuver for the brig must cross directly in front of the American frigate which is now turning south and east (point 5 Chart 2). You, as captain might chose to bear up into the wind and sail aft of the frigate, but I didn't like trying that in the fog and in the face of the strengthening NW breeze. Point 6 Chart 2 shows them all on the NNE tack.

Back on Chart 1 I show the brig turned back north and closing with Surprise. At point 5 I have it "alter course" as POB says: "Now, in answer to a signal, she was bearing up with the evident intention of crossing the Surprise's stern and raking her, firing a broadside that would run the whole length of the ship." But Surprise's stern-chase guns bring down the brig's square foresail causing it to shoot up into the wind, her square foresail down on deck, her fore-and-aft mainsail swinging her helplessly out of control." NOTE: I don't quite understand this loss of control. I would have expected on a NNE reach, the main sail would be pulled far back causing the brig to heel to leeward, the square foresail also pulled around as far as it could go. When the foresail goes down, the brig should have looked like a simple fore-and-aft-rigged ship on a reach and a skillful helmsman could quickly adjust to the loss of the foresail. Of course, if the foremast goes by the board into the water it could drag the brig around, but not into the wind, and anyway POB sails it fell "down on deck". Can anyone help with this?

After heading the iceberg

Another conundrum now occurs. As Surprise passes the iceberg closely to the north, the American frigate turns and fires a broadside (point 6 Chart 1), both bringing down Surprise's mizzen, and hitting the iceberg causing ice to fall just aft of the passing ship. But Surprise escapes and the American must tack (Chart 1) to get around the iceberg on its north side (now also perilously close to the islands). But now the Surprise must change course because without its mizzen, it cannot sail so close to the wind. Indeed, Jack says it must put before the wind (p. 246): we must put before the wind or close on until we can ship a jury-mizen." And which direction must that be in a NW breeze? Why close on SE of course. Putting the wind on its quarter (two points) would force the Surprise ESE back into the icebergs! Now this will never do, but that's just the course she's on for, when the American is again sighted coming around the iceberg (point 7 Chart 1), we are told (p. 247): "By this time the Surprise, keeping the wind one and two points on her starboard quarter as far as the ice allowed, had traveled ten miles in a straight line-" And so we are left wondering what is going on. I have chosen to get out of this dilemma by changing the wind direction to SW. In such a wind "keeping the wind one and two points on the starboard quarter" would send it about east, a bit north, just the direction from the ice and towards home. I get some help from POB in this radical solution for in the last sentence of p. 247 Jack says: "I hope that the westerlies or south-westerlies will go on blowing...."

Jack goes to supper and so into the night. The next morning the American is still there, but in one of POB's now accustomed "Deus ex machina" ploys it inadvertently sails up a dead end ice lead and must be towed west by the ship's boats effectively taking it out of contention. It sends a flag message, H,A,P,PP,Y,R,E,T,U,R,N. Surprise answers in kind and sails on to keep its appointment with a lightening bolt, a lost rudder, and another "Deus ex machina" encounter with the two-decker, Bernice, and salvation.

4. Loose Ends and Questions

Looking over Chart 1 after this all was finished several questions occurred to me. First, where do the brig and frigate come from originally. Let us assume that they are trailing the China ships. It is possible that once the third merchantman clears the islands that all attention is focused on them or that the fog hides their arrival by the same route. The timing is good enough--suppose they sight Surprise at point 2 and come down directly south, then through the fog find that Surprise has tacked to the NNE and turn to intercept. This would bring them in at about the place I have them. Looking at Chart 2 I have them arriving to intercept the Surprise after it has tacked to WSW, but wouldn't they have originally been approaching to intercept Surprise on its NNE tack? Probably not since they would always want to keep between Surprise and the China ships. Thus they would approach a bit south to cover a tack to the WSW, which is just what happens.

Charles Keller

35* 53' N 106* 19' W


Text copywrite 1996 Charles Keller. Please direct comments to him at alfanso@roadrunner.com.

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Last modified Nov. 26, 1996.

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