Provisional GSGS series 4229. First Edition-AMS 1. Copied from an Italian Istituto Geografico Militare map dated 1933 with principal communications revised using smaller scale material up to 1938. Compiled by the U.S. Army Map Service in 1944. Road classification is NOT based on reconnaissance, reliability is uncertain. The French Lambert II grid on map series of France which adjoin the western edge of this series, is computed on the geographicals of the French datum. To convert French geographicals to the Italian, upon which the grid of this map is based, subtract 1.9 seconds from the latitudes and 6.8 seconds fromt he longitudes. The meridians are based on the meridian of Rome, which is 12 degrees, 27 minutes and 7.1 seconds east of Greenwich. Contour interval 50 meters. North Italy Zone Grid.