[MARINE] DUCOM, Nautical Observations Course - Lot 179

[MARINE] DUCOM, Nautical Observations Course Containing all the knowledge of astronomy relative to the various problems of navigation, the best methods of latitude and longitude by observation, how to set marine watches and their use to determine longitude, the theory of rectification of observation instruments, how to train the eye to observe distances, a new method for determining lattitude by a single non-meridian height, deduced from heights taken in a very short space of time, the way to judge all observation methods with the simplest notions of geometry, a method for calculating the direction of currents and their effect.... the manner and means of executing all problems relating to esteem. Followed by a collection of the best tables, one of which gives the latitudes and longitudes of the main ports, harbors, shallows, rocks, etc., for all parts of the world. Another of these tables offers sailors a newly invented system of signals for merchant ships of all nations. Bordeaux, Pinard, 1820-1822. in-4 worn half-binding, 320 p. Freckles This work has the great interest of containing the first international nomenclature of signals for use by merchant ships.