Scale 1:500,000. 1 in. equals approximately 8 miles ; Lambert conformal conic projection based on standard parallels 33° and 45° (W 90°18ʹ00ʺ--W 81°38ʹ00ʺ/N 36°40ʹ00ʺ--N 34°58ʹ00ʺ).
Note
Includes list of "Limestone and dolomite quarries active as of 1960" keyed to map.