Abstract
Characters of celestial line of position plotted on chart of Lambert conformal conic projection, e.g. ICAO WAC one millionth, are investigated. Error of length of the intercept caused by neglect of change in the magnification along meridian, error of the position of intercept terminal caused by the difference between straight line intercept and great circle intercept, and error of the direction of position line due to the convergency of meridians give final effect of third order infinitesimal or less to the position of ship or aircraft, and is practically neglegible even at high latitude or for high speed air navigation, at lower latitude in which cases the ordinary position line on Mercator chart gives serious error. The full text of the treatise shall be shown on the Contributions from the Marine Research Laboratory, Hydrographic Office of Japan, 1, 1, 20 (1959).
