Examining the 1:50,000 AMS topo for San Francisco, Calif., surveyed 1942 and published 1946, I note the blank areas where Naval Station Treasure Island, NAS Alameda, Oakland Army Base and even San Francisco International Airport should be. The Presidio of San Francisco does however appears. The blanking of certain military facilities is routine in wartime maps and charts. This particular map bears no “Restricted” or other classification markings. Is it fair to assume that Restricted or other classified versions of this series exist, and are they held in any depositories or libraries? Gratefully, Rick Prelinger Rick Prelinger / @footage Prelinger Archives, San Francisco http://www.prelinger.com [log in to unmask] Associate Professor, Film & Digital Media, UC Santa Cruz [log in to unmask] Prelinger Library (http://www.prelingerlibrary.org), a member of the Intersection Incubator, a program of Intersection for the Arts providing fiscal sponsorship, incubation and consulting to artists (http://www.theintersection.org).