The June meeting opened promptly at 8 pm when the Chairman, Malcolm King, called the meeting to order and commenced the usual monthly notices. He started by remarking that monthly attendance remains at a consistently high level, with the May meeting attracting 87 people. He then moved on to the by-now regular "This Month in History" feature, which on this occasion featured D-Day, Waterloo and Sir Arthur Conan Doyle in South Africa during the Anglo-Boer War.
Other notices followed. The attention of members was drawn to the super-large box of DVDs which was being raffled. Titled "The Great War", this set will be raffled and then drawn at the July meeting. Members were also urged to visit the Museum and follow the D-Day Trail through the Museum. This fascinating exhibition will be open from 6 June onwards, until further notice. Considerable up-dating has taken place in the Museum recently and the Society has arranged for a two-hour guided tour to catch up on these. It will be led by our own well-known Museum Liaison Officer, Hamish Paterson, and will include a bring-your-own picnic on the lawn. The price will be R30 per head and the tour will take place on either 18th or 25th October. Members will be advised of the date closer to the time.
Another visit to our favourite little town of Val is being planned for 27/28 September and this time will include places of military interest in and around Standerton. For those interested in weapons and uniforms, there will also be a large scale exhibition with battle enactments held at the Museum on the weekend of 2/3 August.
Malcolm then introduced the curtain-raiser speaker. This was the popular ex-chairman, Marjorie Dean, who had bravely stepped forward at extremely short notice to stand in for the advertised speaker, Sandi McKenzie, who had fallen ill. The subject of Marjorie's talk was "President Lincoln's Spy". Marjorie started by giving a brief outline of the causes and events leading up to the U S Civil War in the 1860s. This period coincided with Britain's apex as the industrial leader in the world, and in particular with the pre-eminence of Liverpool as a premier port.
Because of its position on the West Coast of the United Kingdom, and its proximity to the industrial Midlands and the Lancashire cotton mills, Liverpool carried on a transatlantic trade with the Americas. This was particularly true of its links with the Southern states of the U.S A. Vast quantities of cotton were imported from the American South and industrial exports flowed in the reverse direction. When the Southern states broke away and formed the Confederacy it was natural that they should strive to maintain their links with this important port. To this end, the Confederate Government engaged the services of a cotton-trading company, Fraser, Trenholm and Company, as its UK agent and as the war progressed this firm became, to all intents and purposes, the banking arm of the Confederacy.
There was also another reason to stay connected with Liverpool and this was its status as a shipbuilding centre. The Confederacy was particularly vulnerable to blockade by the US Navy and one of its first priorities was to build up a Navy of its own, to prevent and break this blockade. The combination of shipbuilding and business relations made Liverpool the obvious place, outside continental America, for the Confederacy to acquire ships. With time, Liverpool would become the unofficial home of the Confederate Navy.
Although initially pro-South, as time went by Britain started enforcing its neutrality and the British government, and particularly the people of the Midlands, took a very dim view of these Confederate activities. It became necessary for all sorts of subterfuges and ruses to be employed to build and man these ships without falling foul of Britain's neutrality laws. With this in mind, the Confederacy despatched James Bulloch to liaise with Fraser, Trenholm and Company and the shipbuilding firm of Lairds, to ensure the completion and delivery of these ships. The Northern States also sent a representative specifically to confound Bulloch and his schemes. This was a 41-year old New Jersey Quaker lawyer named Thomas Haines Dudley and he was appointed as the US Consul in Liverpool, a post he held from November 1861 to the autumn of 1872.
Dudley immediately set up a network of spies and informers in Liverpool who gathered information on all things Confederate, and especially the activities in the local shipyards. This information was passed on to the US Ambassador in London, who then lodged the necessary complaints. The situation gradually became a game of wits between Bulloch, Lairds and Dudley. At first the Confederates managed to prevail and a number of ships, the most famous being the Alabama, were got away to sea to act as raiders. Ultimately, Dudley was able to prevail, scoring his biggest victory when he was able to stop the delivery of two ultra-modern "rams" to the Confederate Navy. These were iron-clad warships, specifically designed to ram and sink the wooden US warships carrying out the blockade of the South, and their acquisition by the Confederates would have changed the war at sea.
Dudley grew his spy-ring to cover much of the UK and his efforts at sabotaging the Southern war effort played a significant role in swinging British opinion to the side of the North. His efforts were recognised by the North, which pumped more and more money and support to him.
On completion of his time in Liverpool, Dudley retired and returned to New Jersey, where he built a large home in Camden and became one of the State's leading citizens. His estate is now a national park. His adversary, Bulloch, stayed on in Liverpool and became the director of the Liverpool Nautical College. His nephew, Theodore Roosevelt, became President of the United States.
A brief question period followed this most interesting talk. It was then the turn of Malcolm to introduce the next speaker. This was our well-known fellow member Gil Jacobs.
In addition to owning his own property and investment business, Gil has an active interest in computer graphics and astronomy. He is a keen member of many astronomical societies and has lectured in computer programming and at the Johannesburg Planetarium. The subject of his talk was "The Longitude Problem".
While Gil and our computer wizard Colin Dean set up Gil's computer for his talk, Malcolm used the opportunity to inform members of a special offer of two tickets for the price of one for a cruise to the island of St Helena on the MV Astor, over the period 5 November to 26 November. Gil then commenced a most interesting and well-illustrated talk.
Position on the surface of the Earth can be specified using a two-dimensional co-ordinate system. The co-ordinates are longitude and latitude and they are sufficient to specify a position uniquely. In the eighteenth century, navigators already knew how to determine latitude, but could only guess at their longitude using "dead reckoning" and the further they travelled the less useful a dead reckoning position became. A navigator needs to know two things to determine longitude:
1. The local time, and
2. The time at Greenwich.
The local time could be obtained from noon observation of the sun, with a sextant. The instant when the sun is at its highest altitude above the horizon is the time of local noon. The problem was simple to state - how can one know the time at Greenwich when one is many thousand of miles away, after a period of several months? The problem of finding the longitude was taken very seriously, so seriously that in 1714 the English parliament offered a very substantial reward for finding a solution to this problem. The reward was:
10 000 pounds sterling if the longitude could be found to within one degree;
15 000 pounds sterling if the longitude could be found to within two-thirds of a degree;
20 000 pounds sterling if the longitude could be found to within one-half of a degree
after a voyage of six weeks. (20 000 pounds was a fortune in the early eighteenth century!)
The body of persons who would decide the winner became known as "The Board of Longitude".
An accurate and reliable clock would solve the problem. Unfortunately, such clocks did not exist at the time. Clocks were lubricated with vegetable oil, which soon became rancid. The clock then had to be stopped and cleaned. Pendulum clocks would not keep good time at sea because of the ship's motion.
Sir Isaac Newton did not believe that it would be possible to develop a clock which could keep time accurately enough on a ship at sea. As the Moon moves in its orbit around the earth, it is seen to move against the background of the stars. Why not used the moon as a clock? This was the solution proposed by the astronomers.
In order to use this method, it would be necessary to predict the moon's position accurately - to within one arcsecond. (An arcsecond is a sixtieth of an arcminute.) Unfortunately, the moon's motion is very complicated as it is affected the gravitational pull of the sun and the planets.
The Royal Observatory in Greenwich was established in 1675 for the sole purpose of solving the longitude problem. The first Astronomer Royal, John Flamsteed, proved that the rotation of the earth was constant enough for the determination of longitude. He also made an accurate catalogue of star positions. The second Astronomer Royal, Edmond Halley, spent 18 years studying the moon's motion. Tobias Meyer published a lunar theory based on Euler's work, which enabled longitude to be determined to an accuracy of one degree. In 1762 he improved the accuracy to 16 arcminutes. (One arcminute is a sixtieth of a degree.) The double reflecting quadrant was invented by Hadley in 1731 and could measure angles with an error less than one arcminute.
The scene was set for the introduction of what was known as the "Lunar Distance" method. The fifth Astronomer Royal, Neville Maskelyne, introduced the Nautical Almanac which was first published in 1767 and has been published every year since then. These almanacs contained tables showing the lunar distances of seven bright stars and the sun, for ever three hours. This was continued until 1905. The lunar distance method was cumbersome and difficult, but once astronomers had prepared calculation tables, a longitude could be calculated in half an hour.
John Harrison (l693-1776) was a carpenter who could make accurate clocks. He solved the lubrication problem by making the working parts out of an oily wood, lignum vitae, making the clocks self-lubricating. He also invented:
The "Going Ratchet", which kept a clock running while it was being wound.
The gridiron pendulum, whose period was unaffected by changing temperature.
The bi-metallic strip, used to make balance wheels independent of temperature.
The grasshopper escapement, which minimized friction and did not need lubrication.
He could make pendulum clocks that were more than accurate enough to solve the longitude problem, but how was such a clock to maintain its accuracy on a ship which was always pitching, rolling and yawing?
From 1735 to 1759 Harrison made three clocks, known as H1, H2 and H3. H1 was taken to sea and performed very well. Lt. Commander Rupert Gould, who restored Harrison's clock in the early part of the twentieth century, believed that H2 would have qualified for the 10 000 pound prize. H2 and H3 were not taken to sea - Harrison was not satisfied with the performance of H2, and H3 was outperformed by H4. Harrison was awarded the Copley medal by the Royal Society in 1749.
Harrison completed H4 in 1760. H4 was radically different from the other clocks. H4 looks like a very big pocket watch. Harrison had decided that the best solution to the problem of a ship's motion was a very fast-moving balance wheel. In 1761 H4 was taken on a voyage to Jamaica. The ship departed on 18th November and Jamaica was reached on 21st January. H4 was then five seconds slow, which corresponds to an error in longitude of 1.25 arcminutes - after more than 9 weeks! Its accuracy was much better than the requirement for the longitude prize, but the Board of Longitude insisted on another trial. The clock was taken to Barbados in 1764 when again it performed excellently, but the Board of Longitude was still not satisfied! H4 was accompanied on these voyages by Harrison's son William - Harrison was now too old for a sea voyage.
Kendall made an almost exact copy of H4, known as K1. K1 was used by Captain Cook on his second voyage and proved once again that a chronometer could be used to determine longitude. Cook called K1 "our faithful guide through all vicissitudes of climates".
As the Board of Longitude seemed not to give Harrison his just reward, an appeal was made to King George III. Harrison and his son were granted an audience. "By God, Harrison, I'll see you righted!" the King said.
The Board of Longitude had by now taken possession of all Harrison's clocks, so he made a fifth clock, which became known as H5. This clock was tested under the personal supervision of George III and its error was only 4.5 seconds after ten weeks!
As a result of the King's intervention, parliament awarded Harrison most of the balance of the prize money due to him three years before he died.
Harrison's method of finding longitude was adopted by more and more navigators as chronometers became less expensive. The cumbersome lunar distance method then became obsolete.
A question period followed this most interesting talk, after which those present were invited to tea and coffee.
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