Multimedia Gallery
- Topic: Navigating At Sea
A navigator can take measurements of the ship speed and direction and the effects of wind and current. He can estimate the ship’s location fairly accurately–at least over short distances.
Deer, North America (Cervus macrotis)
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Made by Jesse Ramsden in 1775, this machine permitted the automatic and highly accurate division of a circle into fractions of degrees of arc. The machine led to mass production of precision octants and sextants.
Dolphins (Lagenorhnychus lateralis, Delphinus borealis)
This clock was made by Johannes van Ceulen around 1680.
This illustration from 1766 depicts the improved escapement in Le Roy’s marine clock.
Ferdinand Berthoud, a Swiss clockmaker serving the king of France, produced many marine clocks.
This illustration is the frontispiece to The Mariner’s Mirrour, one of the most famous collections of sea charts from the 16th century.
Italian astronomer Galileo Galilei competed for two longitude prizes in the 17th century.
