Accurate Timekeeping At Sea

Longitude by Dava Sobel was a book that explained in great detail the struggle to find longitude at sea and way it was so necessary. Sobel talked about the tragedies that followed with not finding longitude at sea and then the discoveries and trials that had occurred to find a final solution. Throughout the book, you understand the urgent need to find longitude why it was so hard, and what it really took in order to come to the final discovery. As you read through this paper you will get an understanding of the topics Sobel talked about in her book such as, the shipwrecks and tragedies that occurred without longitude at sea, the two competing methods to find longitude and the man who discovered it.

Britain today runs on GMT, which stands for Greenwich Mean Time. The time is exactly five hours ahead of the time it is in Connecticut, which runs on EST, or Eastern Standard Time. The countries: United Kingdom, France, Spain, Algeria, Mali, Ghana are all in the GMT time zone. For these countries, this means the line located on the Greenwich Meridian runs through them. During the Industrial Revolution, Britain decided it wanted to set a standard time that would be followed by everyone. It was the first country to do this. Railways in Britain, “...cared most about the inconsistencies of local mean time, and they forced a uniform time on the country,” (Document 7). The country felt compelled to adapt a new standard of time, after railway workers expressed complaints of inconvenience. This standard of time was known as, London Time. Furthermore, in November 1840, the Great Western Railway was the first to follow London Time, which eventually influenced other railways to do the same. By 1847, the majority of railways ran on London Time (Document 7). Moreover, it was later approved that all stations be adopted to this new unit of time, known as GMT. This recommendation was made on September 22, 1847, by the Railway Clearing House, which eventually received approval from the General Post Office (Document 7). This was much more convenient for railways, as they could have a

S- together the angles make a coordinate that can pinpoint any geographic position on the surface of the Earth, or any other

When Banneker was 22, he borrowed a pocket watch from a neighbor, took it apart, drew a picture of each component, put it back together, and then returned it. Banneker then proceeded to carve, out of wood, enlarged replicas of each part. Figuring out the proper number of teeth for each gear and the necessary relationships between the gears, he made a working wooden clock that kept accurate time and struck the hours for over 40 years until it was destroyed in a house fire.

He used a hand bearing compass, pointed at a lighthouse or some other landmark and looked across the lubber’s line into the bowl, taking bearings of two or more objects, and reading the direction or bearing of that object, off of the compass. Then, he plotted them onto his chart. Where the lines crossed, was where he was. It was that simple. The GPS was for his clients. It made them feel better, not him.

When the clock is moved away from sea level gravity would slightly decrease causing the clock to lose time. Pendulums are the most accurate at sea level.

Much of the new technology that they brought over, however, was borrowed from various people and cultures along their travels. Some of these new technologies include the compass, which they used to figure out which direction they were travelling, and the astrolabe, which aided the sailors in trying to find out how far north or south they were from the equator. Another borrowed technology that greatly benefitted the Europeans on their travels was cartography; this is the science of map making. This was probably one of the most beneficial discoveries to the Europeans because it allowed them to draw out where they had been and where they were

Be able to list and describe the 3 main tools used to measure latitude in early navigation

Observation that pendulum clocks were affected by summer that the thermal expansion and contraction of the pendulum was changed by changing the temperature which was a large source of error, this error was solved by George Graham when he invented the temperature-compensated pendulum back in 1721 and the gridiron pendulum by John Harrison in 1726.Pendulum clocks remained the world standard for timekeeping accuracy for over 200

The race to find longitude at sea was a race of endurance, spanning multiple centuries, countries, and methods. John Harrison’s final clock, H4, was the culmination of that race, an elegant, practical, and direly needed winner. But this race wasn’t solo; instead it was a relay. Harrison needed the knowledge and support of Enlightenment Science and the Royal Society to accomplish what he did. Without past horological innovation, patronage from the Royal Society, and the experimentation through a voyage to Lisbon, Harrison’s clock would have never succeeded.

compass, the ship, and the quadrant allowed Europeans to sail across the open ocean. The

In the 1400’s, Europeans were finally able to explore across the Atlantic Ocean b/c if the astrolabe (finds latitude – from ancient Greece) and the compass (invented by Chinese): Also used triangular sails (developed by Arabs), which allowed ships to zigzag into the wind.

The Operations of the Geometrical and Military Compass (1604), which revealed Galileo’s skills with experiments and practical technological applications.

Most of these items are related to the study of heavenly bodies and the subject of astronomy. The Celestial globe is used to observe the positions of the stars and other celestial bodies. The Two Quadrant are used to read time, it allows the height of the sun and the angle to the horizon to be calculated. A sundial is an instrument used to measures apparent solar time, by measuring the position of the shadow of the sun as it changes through the day. The Torquetum is an object used to determine the relative position of heavenly bodies and tell the time. According to the experts, the sundials reveal that it is 10:30 am on April 11,1533. This tells us that exact date and time of Dinteville?fs visit to London.

This essay examines the question: How does GPS rely on geometry and trigonometry now that there are satellites? Has the function of geometry and trigonometry in triangulation and navigation changed since satellites were