THE LIFE AND TIMES OF JOHN HARRISON
|
1693 |
Born
in Foulby, Yorkshire in England to carpenter, surveyor, and village clerk,
Henry Harrison |
|
1700
(?) |
The
Harrison Family moves to Barrow near the Humber River |
|
1707 |
Four
ships under the command of Admiral Sir Clowdisley Shovell are wrecked off the
coast of the Scilly Isles. The
accident is blamed on faulty navigation.
|
|
1713-1717 |
John
Harrison makes three pendulum clocks almost completely out of wood.
|
|
1714 |
The
English Parliament passes an act offering Á 20, 000 to the
inventor of a device that will accurately measure longitude. |
|
1720-1722 |
Sir
Charles Pelham of Brocklesbury Park hires Harrison to build a tower clock for
his new stables. Harrison makes the
clock from a wood that naturally gives off oil, thus the clock never needed
oiling. All metal parts were made of
brass, which does not rust. The clock
still runs. |
|
1720s |
John
Harrison and his brother, James, work as clockmakers in Barrow. Harrison tries to make more accurate
clocks. He eventually makes clocks
accurate within a second per month. |
|
1730 |
Harrison writes of making a clock
that will run correctly despite the movements of a ship. This clock would be able to help sailors
keep track of a ship’s longitude. |
|
1735 |
Harrison completes his first “sea
clock”-known as H1. |
|
1736 |
The H-1 goes to sea aboard the HMS Centurion. Although the clock seems to work fine,
Harrison considers the trial a failure and begins again. |
|
1737 |
The Board of Longitude meets for the
first time. Harrison asks for a grant
to build a second clock, which will be better than the first. He also moves from Barrow to London. |
|
1739 |
H-2 is finished, but never tried at
sea. Harrison begins work on a third
clock. |
|
1744 |
Harrison is awarded the Copley Gold
Medal by the Royal Society. |
|
1760 |
After nineteen years, Harrison
finally finishes H-3, and shows the Board of Longitude an almost completed
H-4. H-4 looked much like a pocket
watch. |
|
1761 |
Harrison says H-4 is ready for a
trial at sea. Harrison, being too old
to take a sea voyage, sends his son William in his place. In November, H-4 is tried aboard the HMS Deptford. The trial is deemed a success. |
|
1764 |
H-4 and William Harrison sail for
Barbados on a second trial of the latest clock. |
|
1765 |
The second trial of H-4 is declared a
success by the Board of Longitude.
The board refuses to award Harrison the prize money until he reveals
the workings of the clock. Later
that year, Harrison explains the clock and receives half the prize. |
|
1772 |
Harrison makes one more clock, H-5,
and enlists the help of King George to test its accuracy. That summer, Capt. James Cook sets sail
with a replica of H-4. |
|
1775 |
Cook returns with maps of the South
Sea Islands, which he says were accurate thanks to the replica of H-4,
“trusty friend, the Watch.” |
|
1776 |
John Harrison dies at the age of 83. |