Equator, Prime Meridian and Lat/Lon Locations, 1930's, 20 covers from ships crossing the equator, the prime meridian and having latitude and longitude locations in the killer bars, interesting locations include "The Knuckle Lat 39 Long 47", "Pacific Triangle", "Domaine of Neptunus Rex", "In Domain of Neptune", etc., some cacheted but collector preferred strong strikes of postmark and killer readings, VF overall. Estimate  $50 - 75. $0 (Image)