Friday, June 24, 2016

Navigator's Week: Sailing Directions

Today's guest post once more comes to us from Lena Mosser, a PhD candidate at Eberhard Karls Universität. Lena's doctorate dissertation is on masters in the Royal Navy, and she brings that expertise to bear with this short piece.

‘From Ushant to Scilly ‘tis thirty-five leagues’: Some musings on sailing directions

With all the fascinating new developments going on in eighteenth-century navigation, it is easy to forget that it was not all sextants and chronometers. Even the best instruments and new techniques, even in the hands of the most experienced and skilled navigators, reached the limits of their usefulness once a ship was in coastal waters, which means that a considerable part of eighteenth-century navigation is actually better described as good old-fashioned pilotage. Pilotage demanded completely different skills and equipment of the practitioner than blue-water navigation: in coastal waters, what served a navigator better than any new-fangled instruments were a sounding lead, a good memory and a sharp-sighted lookout, as well as, of course, sailing directions.

Detail from "Earl of Cornwallis Bound to Bengal,"
William Gibson, 1783
Courtesy of The Mariners' Museum and Park, Newport News, VA.

Sailing directions have something decidedly ‘low-tech’ about them. The earliest written ones I have seen were used by ships of the Hanseatic League in the fourteenth and fifteenth centuries, but they are almost certainly very much older. They are descriptions, either written down or memorised, of distances, depths, landmarks and other topographical information for particular waters or sailing routes. In other words, sailing directions were pilots to take away and carry with you, even where live pilots might not be easy to come by.

Sometimes, they were rhymed so as to make memorisation easier. In fact, most people with an interest in maritime history or seafaring in general will probably know at least one example, perhaps without even realising: parts of the famous sea song Spanish Ladies sound suspiciously like sailing directions. The second verse contains something that is more or less a (somewhat abbreviated) manual of how to proceed when entering the English Channel from the south before coming in sight of land but suspecting that you are ‘in soundings’:

We hove our ship to, with the wind from sou'west, boys
We hove our ship to, deep soundings to take;
‘Twas 45 fathom with a white sandy bottom
So we squared our main yard and up Channel did make.

In the third verse, the most important landmarks – such as prominent headlands and lighthouses – that a ship sailing up the Channel will pass are listed:

The first land we sighted it was called the Dodman
Next Rame Head off Plymouth, Start, Portland and Wight
We sailed by Beachy by Fairlight and Dungeness
And then we bore up for the South Foreland Light.

Detail of South Foreland Light from "A Packet Boat Under Sail in a Breeze off the South
Foreland," Thomas Luny, 1780, Yale Center for British Art.

I don’t know if these were ever actually used as sailing directions, or whether they mimic the real thing, but the detail given in them, with its references not only to landmarks but also to depths, composition of the sea floor, and hints at how to work the ship suggest that they were.

One beautiful example that dates from around the mid-eighteenth century is Wadhams Directions, sailing directions from Cape Bonavista to the Wadham Islands. It was famous among eighteenth-century navigators and I came across a copy in the journal of John Dykes, master in the Royal Navy, who served with Edward Pellew on the Newfoundland station in the 1780s.[1] The directions open with the magnificent lines:

From Cape Bonavista to the stinking Isles,
The course is North full forty miles
Then you must steer away NE
Till Cape Freels Gull Isle bears WNW
Then NNW thirty-three miles
Three leagues off shore lays Wadhams Isles.

The rest is a more in-depth description comprising another thirty-eight atrociously rhymed lines, but even though the poetic quality might make philologists cringe, it certainly serves its purpose very well; how well, you can tell from the fact that, while writing this, I cannot help constantly reciting in my head “When within the channel you are shot/Three fathom of water you have got/Port your helm and do take care/in the mid-channel for to steer”. I think there is something touching in how the directions address the navigator directly, like a trusty friend cautioning against narrow passages and sunken rocks:

Therefore my friend I you advise
Since those rocks so dangerous lies
That you do never amongst them fall
But still endeavour to weather them all.

Detail from "To the Survivors and Relations of the Unfortunate Persons who Perished in the
Halsewell," P. Mercier, S.W. Forbes, and Rawlinson, 1786, National Maritime Museum.

These sailing directions had the reputation of being the best for the Newfoundland coast, and you can in fact follow them easily on a chart (I have not so far had an opportunity of running a field trial). Thus, despite their old-fashioned appearance, it is no wonder that sailing directions in general remained in use alongside all innovations in navigation, and are still in use today.

[1] Log of John Dykes, master, HMS Winchelsea, National Maritime Museum (Greenwich), Caird Library, LOG/N/W/1.

Thursday, June 23, 2016

Navigator's Week: Effective Nautical Interpretation

Today's entry in Navigator's Week comes to us from Robert Fryman, PhD, an adjunct professor at Georgia Perimeter College, reenactor with HMS Acasta, and veteran of the United States Coast Guard.

Effective nautical interpretation of the “Age of Sail” requires that the docent/reenactor go beyond proper clothing and appearance and the description of life at sea.  This is acutely important when describing and explaining the technological differences which exist between operating a vessel in the present as compared to the period from 1700 to 1815.  The procedures of navigation are illustrative of this, particularly as modern GPS systems have removed today’s travelers from the basic skills of map reading and plotting a course, yet such abilities would have been common place for sailors of the 18th and early 19th centuries.  Acquiring an applied knowledge of navigation skills therefore better prepares the interpreter/reenactor with not only a working understanding of the tools of navigation, but also an enhanced appreciation for sailors to perform complicated calculations without the benefit of electronic devices.

Detail from portrait of Master William Bligh,
John Webber, c. 1776, National Portrait Gallery (Australia)

Such an understanding of the tools and procedures of navigation was an integral component in the development of my interpretive persona as a member of the HMS Acasta.  I was able to approach this with a fundamental grounding in navigation gained while serving with the U.S: Coast Guard, but while the basic algorithms for plotting speed, distance, and position have remained the same, the tools for their calculation have not.  From reading period accounts of navigation procedures, the tools used for calculating the aforementioned variables, apart from the octant of sextant, included the sector, Günter Rule, dividers, parallel ruler, and tables of sines, cosines, and logarithms.  The sector and the Günter Rule were the equivalent of the 20th century slide rule, and both contained a number of different scales.  The user perform mathematical computations by placing the tips of a pair dividers on the appropriate scale.  Tables of sines, cosines, and logarithms were commonly found as appendices of mathematical treatises, such as the 1796 edition of John Love’s Geodesia and other publications including the American Coast Pilot, reducing the need for the navigator necessarily to be familiar with how to determine these values.

Detail from "His Royal Highness Prince William Henry," book illustration
for Hervey's Naval History, 1779, British Museum

While I re-learned the art of navigation from the 18th century perspective, I was suddenly struck by the differences that existed in the amount of formal training in mathematics that the sailor in 1790 received compared to that of your average middle school student of today, who by the 8th grade has already been taught Algebra and, in some instances Geometry.  This does not imply that today’s students are more intelligent than their 18th century counterparts, but rather serves to illustrate the impact of inexpensive electronic calculators in accelerating exposure to more advanced forms of mathematics than was previously possible.  I often present students in my Physical Science classes with a stimulated navigation problem where they must determine their position using paper reproductions of sectors.  The result of this exercise was that they gained an understanding of how people were able to solve problems using “primitive” technology while I was able to gain a new perspective on mathematical training of the 18th century sailor.

Through re-learning how to navigate using 18th century tools and equipment I was able to not only to better use the instruments and thus be better equipped to describe and explain their use and function to the public, but also gain a perspective onto the world of the 18th century sailor and his background which allowed him to perform such complicated calculations to venture to new lands.  This new information helps to explain to visitors the impact which modern technology has on the world of nautical navigation.

Wednesday, June 22, 2016

Navigator's Week: The Tools Needed for Dead Reckoning

Today's entry in Navigator's Week comes to us from follower Thomas Apple. Tom was involved in creating the chip log used in the 2003 film Master and Commander: The Far Side of the World. In this post, he writes about the use of dead reckoning navigation.

The Tools Needed for Dead Reckoning

Dead reckoning enabled sailors to navigate when conditions did not permit celestial observations. If you could not see the heavens, day or night, you could not fix your exact position. You must plot your course from the last place you fixed the ship’s position to make an educated guess as to your location. To do this you needed certain data. The better the data and the more skilled the interpretation of it, the more accurate would be the resulting dead reckoning.

In the 18th and early 19th centuries the data was collected at least hourly and temporarily recorded on a log board (figure 1). The log board, usually a slate, recorded the hour, ship’s speed (knots), ship’s course, wind direction, and leeward drift. Extra observations could be recorded if conditions changed within the hour intervals. Observations were usually made at the top of the hour after the bell had rung. They would be transcribed to the log book at least twice daily.

Figure 1 - Slate Log Board

To measure ship’s speed, a log reel and chip were used as well as a small sand glass to keep time. The chip was a quarter circle of wood attached to the end of the log reel line. It acted as a sea anchor that remained largely stationary as the ship sailed away from it. The chip was weighted on the curved edge with a strip of lead to cause it to float with the pointed end facing up. It was attached to the log line with a two or three-leg harness. One leg of the harness was attached to the chip with a peg.
The log reel was constructed of two wooden disks connected by a series of bars that created a sort of drum on which the log line is wound. The bars allowed air to reach the line better making it less prone to rot. This drum rotated on a central axle with a handle on each end (figure 2).

Figure 2 - Log Reel with Chip
The first 12 fathoms of the log line was the stray line to allow the chip to float free of any turbulence in the ship’s wake. After the stray line portion of the log line it was marked with a piece of cloth. After the marker cloth there were knots tied in the line, each to indicate one nautical mile per hour (figure 3).

Figure 3 - Log Reel with Log Line and Chip

The spacing of the knots depended on the size of the sand glass used to time the log line. Thirty- and 28-second glasses were the most common with a 14-second glass used for very fast and small craft. If using a 30-second glass, the knot spacing would be 50.75 feet and for a 28-second glass it would be 47.6 feet. These were usually rounded up to the next whole foot, so 51 or 48 feet were usually used as the knot spacing. The sand glass was constructed of two separate globes of blown glass connected to each other with a disk in between with an orifice to control the flow of sand from one globe to the other. They were often connected to each other using a Turk’s head knot (figure 4).

Figure 4 - 28 Second Sand Glass

To measure speed the chip was tossed over the aftmost rail, the taffrail, and into the water. The log line paid out as the ship sailed away from the stationary chip. When the cloth marker hit the rail, a sailor called out “Turn!” - at which point the sand glass was turned to start timing. The number of knots passing over the rail were counted until the sand glass ran out at which time the person holding the glass called out “Nip!” to grab the log line and stop it from paying out. The number of knots was recorded on the log board. From the time the chip is tossed overboard and the log line nipped, the wind had caused the ship to drift to leeward veering from the course plotted. A protractor was usually inscribed on the taffrail. The crew would lay the log line on this protractor to indicate the angle of leeward drift and then record this angle on the log board. The log line was then given a sharp tug to dislodge the peg in the chip harness allowing the chip to lay flat to the water, making hauling it in much easier.

Also recorded were the water depth, course, and wind direction. Water depth was measured using a sounding lead and line. A compass indicated the ship’s course and allowed determination of wind direction. All of these vital pieces are data were used to plot the actual track of the ship from its last known position to hopefully get the ship to where the captain wanted it to go and out of harm's way from grounding or other hazards.


William Falconer, An Universal Dictionary of the Marine, or, a Copious Explanation of the Technical Terms and Phrases employed in the Construction, ...of a Ship...London: Thomas Cadell, 1780 edn.

William Brady, The Kedge-Anchor or Young Sailors’ Assistant, Fourth Edition, New York: William Brady, 1849.

William Burney, Falconer’s New Universal Dictionary of the Marine, 1815

C. Keith Wilbur, Pirates and Patriots of the Revolution, Chester, CT: Globe Pequot Press, 1984.

Log line, chip, and sand glass are reproductions built by author for use in the movie Master and Commander: The Far Side of the World, 2003. The log reel is based on an original example in the Mariner’s Museum in Newport News, VA and the sand glass and log slate are based on an early 19th century examples in a private collection.

Tuesday, June 21, 2016

Navigator's Week: The Backstaff and Octant

Continuing our focus on navigation, I'm going to talk briefly about the transition between two important pieces of navigational equipment: the backstaff and the octant.

Both instruments accomplish the same task of determining latitude. Latitude, for the uninitiated, is the distance you are North or South of the Equator. Latitude may be found by measuring the angle between the horizon and the sun at its highest point (zenith). There are many ways to do this, and it may be as simple as the use of a quadrant or cross-staff. Neither of those instruments are as accurate as the backstaff, which was sometimes called the Davis Quadrant for its sixteenth century inventor John Davis.

The photograph above was generously provided by E.T. Fox, curator of the Golden Hind Museum in London. The backstaff he holds on the quarterdeck is one that he constructed himself, and you can see more examples of his work here. In this photograph you can see how the staff is used. In order to measure the elevation of the sun from the horizon, you would have to turn your back to the sun, as demonstrated in this video by the Mariners' Museum and Park in Newport News, Virginia.

The biggest drawback of a backstaff is that it is nearly impossible to use for sighting anything but the sun. The backstaff is practically useless for measuring the altitude of celestial bodies at night. This lack contributed to its eventual replacement in the 1730's by the octant. A more accurate instrument, the octant could also measure any celestial body visible in the sky, night or day.

In the mid to late eighteenth century, these instruments co-existed in a period of transition that saw the phasing out of the backstaff. This phasing out is evidenced by cartoons of the period, such as "Ridiculous Taste or The Ladies Absurdity," a 17771 print by Matthew Darly. The version below is in the collection of the British Museum.

Lampooning the tall wigs piled onto the heads of fashionable ladies, Darly is probably not acquainted with celestial navigation as more than just a concept. As part of the joke, he has one dandy gentleman taking a sighting by the wig of the seated woman.

Our macaroni holds a sort of octant (lacking many of the necessary pieces), but he holds it as one would operate a backstaff. Darly is either unaware of precisely how an octant works and so falls back on the general appearance of a navigator working a backstaff, or is intentionally making the scene more ridiculous through the use of an oafish fop who doesn't quite understand what he's doing.

Either way, it is a piece of art that exists in the time of transition between the dominant technologies in determining latitude.

The same is true of R. Attwold's cartoon "The Naval Nurse, or Modern Commander." The first image here is a 1740-1750 sketch from the British Museum's collection, used as a study for the final piece which was printed in 1750. The final engraving featured here comes from the Yale University Lewis Walpole Library.

On the wall of the Boy Captain's cabin is a series of pistols, a blunderbuss, a telescope, and a backstaff.

In the final print, however, the instrument is changed from a backstaff to an octant.

Attwold's point in this cartoon is the youth and inexperience of naval officers. Such young men would be much more open to using newer technologies and newer methods of navigation. Perhaps it is this which accounts for Attwold's choice to replace the original backstaff with the octant.

Just as Attwold erased the backstaff from his image in favor of the octant, the octant would eventually erase the backstaff from the list of essential navigational instruments. The octant itself shortly evolved into the sextant, which remains the primary means of celestial navigation to this day. While the GPS has largely supplanted the use of celestial navigation, sextants can still be found in marine supply stores around the globe.

Monday, June 20, 2016

Navigator's Week: A Few Thoughts on Masters in the Eighteenth-Century Royal Navy

Today's guest post comes to us from Lena Mosser, a PhD candidate at Eberhard Karls Universität. Lena's doctorate dissertation is on masters in the Royal Navy, and she brings that expertise to bear with this short piece.

Kyle Dalton has very kindly asked me to share a few thoughts on masters to tie in with his post on William Bligh and masters’ uniforms. I will focus on their career paths and social backgrounds because there are many misconceptions about just this issue.

The title ‘master’ (in the Royal Navy they were not called ‘sailing masters’) already gives an indication. Before a Royal Navy as such existed, the English crown would hire merchant ships for their military exploits, including the crew and the master. The master retained command of the ship as such, that is, in all nautical matters, while army officers – captains and generals – coordinated the expedition on the whole. When a Royal Navy had been established, with its own captains and generals (who were re-named admirals), masters of merchant ships continued to be hired as nautical specialists: now without their ships, but the title stuck.

"Etched from the Life on Board a Scotch Ship: Cook, Captain, and Mait," artist unknown
(John Kay?), c.1750, National Maritime Museum (UK)
Of course this is something of a simplification, but even in the eighteenth century, masters were essentially still civilians who lent their nautical expertise to the Royal Navy. This is why they received warrants rather than commissions, and why they went without a uniform for so long: they were per definition non-combatants (although there were many warlike individuals among them).

A Navy-internal career path was theoretically possible, but an exception. One popular stereotype about masters is that many of them were ‘failed lieutenants’, passed midshipmen who had given up waiting for a commission. This could not be further from the truth: The vast majority of masters had been trained outside the Navy, and all of them were examined and certified by Trinity House, a civilian authority. They had possibly (though not necessarily) attended a ‘mathematical school’, had served an apprenticeship at sea (usually for seven years) and were, by the time of entry in the Navy, already at the pinnacle of their profession, being masters or at least chief mates of merchant ships.

This, in fact, sometimes led to clashes between masters and captains, since masters who had commanded merchant ships before were unused to having superior officers. If such cases came to a court martial, the court often treated masters leniently because they were ‘unacquainted with the customs of the service’. Many masters returned to the merchant service at some point, a liberty which was possible through them being warranted rather than commissioned.

Portrait of James Cook as Master of the Pembroke
Sculpted by T. Major, 1759, National Library of New Zealand

They usually came from social backgrounds that were situated fairly firmly in the ‘middling stations’ of society; very similar, in fact, to the backgrounds of most commissioned officers. Many of them came from families with seafaring backgrounds, with fathers, uncles, older brothers or cousins who were also shipmasters, merchants, ship owners or owners of dockyards. Few masters rose through the ranks in the Navy, at least no more than rose to other positions as officers. Socially, they were very much on a footing with lieutenants – but even so, some of them seem to have envied their colleagues the glamour of a commission.