Author: John James McCracken

Publisher: Rarebooksclub.com

Published: 2013-09

Total Pages: 44

ISBN-13: 9781230063768

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 edition. Excerpt: ...TO BE OBSERVED--Polis COPYRIGHTED 1S21 BY J. J. MCCRACKEN (iN PADS OF 2s) FROM YOUR DBALKR OR BY MAIL FROM J. J. Mcsss2929 NORFOLK. VA. Chapter 4 McCracken Form 4 Star Sight--Aquino--H. O. No. 200 McCracken Form 4--This form is for use in solving the Astronomical Triangle in the case of Stars and Planets by the use of Aquino Tables, H. O. No. 200. It provides for getting the Compass Error, identifying the star or planet from its altitude and azimuth, and where more than one star is observed for getting the G.S.T. from the G.S.T. of the first star, by applying the difference of the watch times of the observations. Since this is a line of position observation the exact D.R. position is of little practical importance, so that the D.R. position of Sun R or Sun S according as it is a morning or evening observation will be quite sufficient. Provision is made for moving the line of position by Table 2 Bowd. for the difference between observed and computed altitudes and for course and distance to bring the line up to some other time of the day. The precepts printed at the bottom of each form will be found a great labor saver and convenience. The Star's or Planet's Local Hour Angle and Longitude of Position Point A--The watch error is found by applying the chronometer correction to the chronometer time of comparison, which gives the G.M.T. of comparison, and the difference between G.M.Tc. and W.Tc. gives the watch error. According to our practice as the Navigating Watch must be set to either L.A.T. or the L.M.T. of some nearby Standard Meridian, when the Longitude is East we subtract G.M.Tc. from W.Tc. to get the W. Err., adding twelve hours to W.Tc. when less than G.M.Tc. so that the watch should be fast on G.M.T.; when the Longitude is West we...