Harrison, John

1693 – He was born near Wakefield, in Yorkshire this year.

1700 – The family moved to the North Lincolnshire village of Barrow upon Humber. First following his father's trade as a carpenter, Harrison built and repaired clocks in his spare time.

1713 - He built his first long case clock this year, at the age of 20.

1730 – He created a description and drawings for a proposed marine clock to compete for the Longitude Prize and went to London seeking financial assistance. He presented his ideas to Edmond Halley, the Astronomer Royal.

1755 – He had become convinced that large machines were not suitable for a marine timekeeper. He had proved a very valuable experiment, teaching him greatly about the overall design and making of balance springs and it left the world two enduring legacies, the bimetallic strip thermometer and the caged roller bearing.

1761 – It took him six years to construct H4, and by then he is 68 years old. He sent it on its transatlantic trial in the care of his son William in 1761.

1776 – He died on his eighty-third birthday. He was buried in the graveyard of St. John's Church, Hampstead along with his second wife Elizabeth, and their son William.