Longitude Essay

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Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time is written by Dava Sobel. The book is called Longitude because it is about a clock maker who was able to determine longitude. Determining longitude was the superlative scientific question in the eighteenth century that Galileo and Newton were not able to resolve.      The principal inspiration behind the invention completed in this book is that many sailors were lost at seas as a result of their ignorance regarding longitude. So, without the competence to determine longitude, many innocent lives were disintegrated at seas.      England’s Parliament was desperate for an answer to…show more content…
1 or H-1 for short. H-1 was bar-shaped, built out of shinny brass, and was big in size. His second attempt was called H-2. H-2 was a heavy weight of 86 pounds, but fitted into a small box as John promised it would. H-2 was also bar-shaped and included an implement to ensure a unchanging drive and a more agreeable temperature reimbursement device. Although its motion was adequately regular and exact for finding the longitude of a ship within the nearest limits proposed by the Parliament, H-2 was not good enough for Harrison. So, Harrison devoted nineteen years to build H-3. The H-3 was the leanest of the sea clocks and was small enough to meet the definition of “shipshape.'; H-3 contained bearings in the caged ball that smoothened the operation with moving parts. Unlike H-1 and H-2, H-3 ran on two large circular balances wheels linked by metal ribbons. In addition, it was controlled by a single spiral spring. Furthermore, Harrison introduced a bi-metallic strip in the H-3. The bi-metallic strip compensates immediately and automatically for any changes in temperature that could effect the clock’s going rate. But after the H-3 was completed Harrison realized that a small watch might be the greatest device to figure out the longitude. As a result, John Harrison completed H-4 in1759. It was very minute for a sea clock, and weighed only three pounds. It had two silver cases and a “genteel white
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