Author : William Thoms
Publisher : Forgotten Books
Page : 528 pages
File Size : 53,9 Mb
Release : 2016-11-12
Category : Science
ISBN : 1334255865
A New Treatise on the Practice of Navigation at Sea by William Thoms Pdf
Excerpt from A New Treatise on the Practice of Navigation at Sea: Containing All the Details Necessary to Enable the Mariner to Become a Good Practical Navigator The sailings are therefore explained by diagrams, and worked out by inspection of the traverse tables only, the same as we actually do at sea, and which is correct enough for all practical purposes; thus relieving the learner from the embarrassment of having several methods given of doing the same thing. The names of the parts of the diagram are inserted against them, which makes it easier to comprehend the meaning of the case, and will be found an improvement upon the old system of marking them alphabetically for the purpose of reference. Every diagram in this work is drawn on the same scale, that is, with the chord of taken from the plane scale, (and which is in general use on board ship.) Instructions are also given how to construct the diagrams, so that the learner may teach himself in a mechanical manner, and which will give him more insight into the nature of the problem than the study of geometry and trigonometry will. In Parallel and Middle Latitude Sailings, diagrams of semi-hemispheres are introduced, showing the contraction of the meridians towards the poles, and the comparative length of the degrees of longitude in the various parallels of latitude. And in Mercator's Sailing, a diagram showing the meridians all parallel to each other, and the expansion of the degrees of latitude towards the poles. Current sailing is gone into at some length, and rules given as they are applied in the practice at sea, In this difficult branch of the study. Taking departures, or ascertaining the ship's place by the bearing of the land, is introduced, and a table given to find the ship's position by two bearings of the same object, having the course and distance sailed between them. This will be found very useful to a ship coasting along shore. As her distance oi? Shore can be easily found by the use of this table; and upon the same principle her distance 01? Shore may be ascertained by projecting the accompanying diagram. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
