This map sheet is one of a series covering that part of the surface of Mercury that was illuminated during the Mariner 10 encounters. Planimetric control is provided by photogrammetric triangulation using Mariner 10 pictures (Davies and Batson, 1975). Discrepancies between images in the base mosaic and computed control-point positions appear to be less than 5 km. No attempt was made to resolve discrepancies in feature positions on this sheet and those on the Kuiper (H-6) quadrangle to the north and the Bach (H-15) quadrangle to the south. The latter sheets were controlled by an earlier, more preliminary net.