Navigation by the mariners plain scale new plain'd: or, A treatise of geometrical and arithmetical navigation; wherein sayling is performed in all the three kindes by a right line, and a circle divided into equal parts. : Containing 1. New ways of keeping of a reckoning, or platting of a traverse, both upon the plain and mercators chart, without drawing any lines therein, with new ways for measuring of the course and distance in each chart. 2. New rules for estimating the ships way through currents, and for correcting the dead reckoning. 3. The refutation of divers errors, and of the plain chart, and how to remove the error committed thereby, with the demonstration of Mercators chart from proportion, and how to supply the meridian-line of it geometrically, albeit there is added to the book a print thereof from a brass-plate to go alone, or with the book; as also a table thereof made to every other centesm. 4. A new easie method of calculation for great circle-sayling, with new projecti | Collections