Here are a some photos of ship's bearing (Figure 3 and 4) made using Lignum Vitae. This pendulum, called a gridiron pendulum, was to be widely employed and most satisfactory. The winning solution, one of more than 100 submissions, was an accurate chronometer that enabled the exact triangulation of location. This pendulum was made of nine rods, five of steel and four of brass, the length of each kind being 100 to 60, that being the ratio of expansion of the two metals. What really surprised me was that Lignum Vitae was used as a bearing material for submarines as late at the USS Nautilus. In 1728, Harrison journeyed to London to demonstrate a compensated pendulum he had invented. Here are two excellent videos on how Harrison built his excellent wooden clocks. The use of lignum vitae eliminates the need for horological lubricating oil 18th-century horological oil would get gummy and reduce the accuracy of a timepiece under unfavourable conditions (including those that prevail at sea). When British Parliament creates an award of twenty thousand pounds sterling to whomever can come up with a solution for determining longitude at sea, a carpenter-turned-clockmaker, John Harrison (Sir Michael Gambon), begins his experiments to build an accurate timepiece unaffected by sea travel. In so doing, he had to defy the establishment, fight to collect a huge prize offered by Parliament, and wait for decades before. Master clockmaker John Harrison used lignum vitae in the bearings and gears of his pendulum clocks and his first three marine chronometers (all of which were large clocks rather than watches), since the wood is self-lubricating. John Harrison (1693 1776), English inventor and horologist, or clockmaker, overcame one of the most challenging problems of the 18th century: how to determine the longitude of a ship at sea, saving many lives. Here is a quote from the Wikipedia on the topic. It is also a rare and potentially endangered species.Īs I heard this person speak, I recalled that reading years ago that John Harrison had made some of his marvelous wood clocks using Lignum Vitae for its self-lubricating properties. During this search, I heard a person mention that Lignum Vitae was the world's densest wood and is known for being so oily as to be considered self-lubricating. He was roundly derided as foolish to predict such a clock. While choosing the wood species for my countertop, I did consider a number of tropical species like teak and ipe. John Harrison, the British clockmaker whose marine chronometers had revolutionised seafaring in the 18th century, proclaimed that he could build a timepiece for use on land that was more accurate than any built by his rivals and would be able to keep time to within a second over 100 days. I enjoy woodworking very much and I am now in the process of making a solid walnut countertop by gluing small walnut pieces together. Figure 1: Lignum Vitae tree is a Caribbean Harrison was a carpenter from Yorkshire who had taken up clock-making just a year before the prize was announced.
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