Today, 2/15/2014, is the first of 2 classes examining the usefulness of various angle measurements from shipboard, and the tools for these measurements, such as the protractor, pelorus, bearing compass, and especially the sextant. We'll start with the bearing compass, easiest to get a measurement with, and easiest to represent the result of the measurement on a chart. We'll then briefly use a protractor, which makes angle measurement conceptually clear, but is inaccurate and awkward in practice. We'll then focus on the sextant, which is so central to traditional navigational methods that it has become a universally recognized icon for the whole maritime industry.

Measuring Angles Associated with Landmarks

The Sextant