National Geographic : 1947 Sep
412 The National Geographic Magazine from Pan Aimericran World Airways With Loran, He Can "See" and Measure Lightning-fast Electrical Impulses This Pan American World Airways navigator looks through the scope of the Loran (coined from Long range Navigation) to fix his position. He does this by measuring the difference in time between arrival of radio signals sent from different Loran transmitting stations. Loran also is used in ship navigation (page 406). Staff Photographer Roiert I. Sisson Split-second Timing Is Required to Flash a Wirephoto Across the Country The cylinder on this Associated Press wirephoto machine and the one on the receiver, though thousands of miles apart, must revolve at the same speed or the picture will be blurred. To keep the two cylinders synchronized, the times of rotation are checked with time signals (page 402).