Practical navigation, [electronic resource] : or an introduction to the whole art, containing many useful geometrical definitions and problems; The Doctrine of Plain and Spherical Triangles; Plain, Mercator, and Great-Circle Sailing; Sundry useful Problems in Astronomy; The Use of Instruments; The Azimuth-Compass and Ring - Dial. The Fore-Staff, Quadrant, and Nocturnal; The Plain - Scale, Gunter's - Scale, Plain - Chart, Mercator's-Chart, both Globes, and Virtues of the Loadstone. Useful Tables of the Moon's Age, of the Tides, of the Sun's Place, Declination and Right Ascension; of the Star's Right-Ascension and Declination; The Latitude and Longitude of Places, and a Table of Meridional Parts; Likewise a new Traverse - Table, and the Use thereof in keeping a Reckoning at Sea: Also a Table of 10000 Logarithms, and of the Logarithm - Sines, Tangents, and Secants. All carefully Corrected with many useful Additions. By John Seller, Hydrographer to the King .