Royal Observatory

Honouring prize-winning clockmaker John Harrison’s Marine Timekeepers – A four-stamp miniature sheet celebrating his perseverance, determination and ingenuity.
Four First Class stamps showcase each of Harrison’s prototypes for measuring Longitude at sea that became known as H1, H2, H3 and H4.

H4, defying conventional wisdom by adopting a watch design went on to win the 1714 Longitude Act just three years before his death after a dispute over the criteria. The next generation of clockmakers subsequently developed Harrison’s ideas into the marine ‘chronometer’ that became an essential part of navigational practice in the 19th and 20th centuries.

STAMPS:

1st Class: Airy Transit Circle Telescope

1st Class: Flamsteed House

1st Class: Great Equatorial Telescope

1st Class: Annie Maunder Astrographic Telescope

1st Class: Prime Meridian

1st Class: Shepherd Gate Clock