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KNOWLEDGE FOR THE DAY
THE STORY OF LONGITUDE
When the earth was flat, navigators of sailing vessels only needed to have knowledge of how to determine locations in the north-south direction. Following the shore line along the coast of Europe was a common method of travel. After all, if ships sailed too far west, they would fall over the edge!
LATITUDE & LONGITUDE are astronomic terms used to define the angular distance measured on the surface of the earth.
LATITUDE is the north-south direction and LONGITUDE is measured in the east-west direction. Both are measured in degrees or hours, minutes and seconds from a fixed meridian. The subject of this instruction is not to educate you as an astronomer, the terms are defined to set the stage for a history lesson.
By the middle of the sixteenth century there were established methods for finding LATITUDE on land or sea. The determination of LONGITUDE was more complex; the solution to it's determination is the subject of our history lesson.
The need for a simple solution for the determination of LONGITUDE was addressed in 1714, by the English Parliament when they authorized a public reward to any person "who shall discover a simple method for determining Longitude". Differing rewards were assigned for the accuracy achieved: 10,000 pounds for a device that would determine the Longitude within one degree, 15,000 pounds for an accuracy within 40 minutes and 20,000 pounds for a solution within 30 minutes. A BOARD OF LONGITUDE was appointed to serve as judge for devices or techniques submitted.
For fifty years, this reward stood untouched; it's solution was conceived to be an impossible task. The BOARD OF LONGITUDE did not meet for several years and had not received a solution worthy of their consideration. The solution to this LONGITUDE problem had stumped the best minds in Europe. Most scientists were convinced the solution would come from a system developed using the stars and the heavens. Time keeping devices of the day were not capable of accurate time; yet the solution was finally provided by a ticking machine in a box. The work of an uneducated carpenter, John Harrison, developed what is now referred to as "THE MARINE CHRONOMETER". A time keeping device made by Christian Huygens had been developed in 1660; Huygen's clock was controlled by a pendulum and was of little value unless sailing in calm waters. Harrison's clock and solution for the Longitude problem required many new features to convert a clock capable of solving the "impossible task" of keeping accurate time while at sea.
The history behind the development of the MARINE CHRONOMETER consumed John Harrison's lifetime and provided many obstacles. Harrison was born in the parish of Wragby, Yorkshire in May 1693. The son of a carpenter, John spent several years in the profession of his father. He also worked as a surveyor, but developed an interest in clocks; he was self taught and studied mathematics and physics. His interest in clocks resulted in developing improvements which improved the keeping of time. At the young age of twenty-two, he built a grandfather clock, made with wood gears, which was capable of an unheard of accuracy.
In his quest to gain this degree of accuracy, Harrison made several improvements to his clocks. He noted that expansion and contraction of the clock pendulum caused clocks to be irregular. Clocks with a common pendulum ran fast in the winter and slow in the summer. Harrison developed "the gridiron pendulum" so that expansion and contraction compensated each other. Because accuracy of a clock is no better than it's escapement, Harrison devised an improved escapement called "the Grasshopper escapement" which was noiseless and nearly frictionless. His grandfather clock, equipped with his pendulum and escapement did not gain nor lose more than a second a month during a period of fourteen years!
John Harrison was thirty-three years old when he decided to seek the award for a solution to the longitude quest. A major obstacle in that effort was THE BOARD OF LONGITUDE. Harrison was advised that rather than contact the board, he should meet with the most noted clock maker in London, George Graham. This meeting with Graham resulted in the recommendation that he delay contact with the board until he had completed his clock. Harrison spent the next two years with this task. His first attempt became known as H1 (or NUMBER ONE).
Completed in 1735, number one was not a graceful looking clock. It weighted seventy-two pounds, was housed in a wooden box (3'x3') and was equipped with gimbals to keep it level. This clock was tested and appeared to satisfy the award requirements; however, the Harrison clock was not accepted. The board never acknowledged his clock as a solution to the longitude problem.
Harrisons struggle with THE BOARD OF LONGITUDE continued for several years without solution. Meantime, Harrison never accepted defeat and was never satisfied. He went on to complete four additional versions of his clock, H2, H3, H4 & H5. None of these efforts satisfied the demands of THE BOARD OF LONGITUDE.
The remaining saga of Harrison's story is intriguing and includes an association with THE KING OF ENGLAND. John and his son
william, did receive the full amount of the award through an act by the ENGLISH PARLIAMENT. The Board of Longitude never acknowledged that John Harrison's clock was the solution to the determination of Longitude. The reader is referred to the books LONGITUDE, by Dava Sobel and LONGITUDE, THE PRIZE by Joan Dash.
John Harrison was offered and refused admission to the ROYAL SOCIETY OF LONDON. He was awarded the COPLEY MEDAL, the highest honor the royal society could bestow. Later John's son William, did accept admission to the society. It is interesting to note that William never had any further activity in clock making after his fathers death.
The ability to determine LONGITUDE was important to mapping the world. The progress of mapping is interesting and it's progress slow. That is another story, stay tuned!
HOPE YOU ENJOYED THIS HISTORY LESSON