Know your Nautical Terminology
We continue our new series of items highlighting with humanity's early exploration of Earth's oceans, lakes, and rivers and leading to the use of watercraft for transportation and commerce.
Last month I covered the introduction of Portolan charts and rutters. These allowed mariners to work their way along the coasts of the Mediterranean and norther Europe. The major problem with these is that they can force long transits between ports that are otherwise fairly close, such as Tripoli to Sicily.
The late 13th century to the 15th saw the development of rhumb-line navigation. Combined with compass & Dead Reckoning ships were able to safely (sort of) sail out of sight of land and cross the Mediterranean.
The mid 15th century to the 16th saw the beginning of astrolabe/quadrant use. Charts gained latitude scales ("latitude charts") allowing the beginning of celestial navigation. This period saw the Columbus, da Gama, and Magellan voyages.
The late 16th century to the 18th saw the combination of celestial navigation and Projected Charts (Mercator 1569). This allowed full open-ocean capability. Rhumb lines, which are curved on gnomonic projection charts, become straight on Mercator projection charts. The development of the chronometer solved the longitude problem (1760s–1770s).
Next month I will discuss the instruments that made this possible.
SpyNavy
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)