Plane sailing

The Age of Discovery lasted from around the 15th to the 17th centuries. Exploration by the Portuguese, Spanish, Dutch, French, German and British powers led to the rise of European colonies in far-flung parts of the world and opened up lucrative trade routes between the New World and the Old. 

During this time, scientific methods of ocean navigation were refined and perfected. Sailors were trained in the use of scientific instruments, such as astrolabes, quadrants, octants and sextants and were educated in the mathematics needed to calculate distance, speed and location.

 > View a selection of navigational instruments from the Library’s collections

Many young boys destined for a life at sea were trained in trigonometry, astronomy, meteorology and draughtsmanship as well as the use of the compass, parallel rules, octants and telescopes. These skills enabled sea captains and navigators not only to plot and set an accurate course using both scientific instruments and their observations of the skies, but also to create detailed nautical charts of the areas of sea and coast they explored. The term plain (or plane) sailing refers to a basic method of navigation based on trigonometry which is used to calculate short distances assuming the sea’s surface is flat (a plane). A more sophisticated version is Mercator’s sailing, which takes into account the curvature of the earth.

 > View a beautifully written manuscript of a student’s course in mathematics from 1763

As ships and the nautical industry grew in importance and became more sophisticated, understanding the terminology used on board ship was vital. Dictionaries and encyclopedias of nautical terms became popular, not just for those involved in the industry, but for students and the general public.

A lovely example is Thomas Riley Blanckley’s A Naval Expositor shewing and explaining the words and terms of art belonging to the parts, qualities, and proportions of building, rigging, furnishing, & fitting a ship for sea.