Orville Coast, Antarctic Peninsula. A 7-man U.S. geological survey party (Mike Boyles, Paul Carrara, Karl Kellogg, Tom Laudon, Pete Rowley, British exchange scientist Mike Thomson and I) spent three months of the 1977-78 austral summer conducting reconnaissance geologic mapping in the rugged mountains of the Orville Coast near the base of the Antarctic Peninsula. In addition to the geologic work first ascents were made of several prominent peaks. Three peaks were climbed in the Sweeney Mountains. On November 7, 1977 Carrara and I climbed the northwest ridge of Mount Edward. Edward is the finest peak on the Orville Coast and its summit ridge offers 500 feet of exposed fourth-class scrambling on excellent rock. Laudon and I climbed the north ridge of Mount Jenkins on December 10. The corniced summit arête is so aesthetic that Boyles, Kellogg and I climbed it again two evenings later. Kellogg and I climbed the third-class north ridge of Hagerty Peak on December 23. Three routes were established in the Hauberg Mountains; the north ridge of Novocin Peak by Carrara and Kellogg on November 26, a north-south traverse of Mount Leek on December 5, by Kellogg and me and the north ridge of Mount Dewe by Kellogg on December 6. On January 11 Carrara and Rowley climbed the west ridge of Mount McKib- bon in an unnamed range of mountains south of the Ueda Glacier and eight days later Carrara, Kellogg and I climbed Tollefson Nunatak, a beautiful isolated spire on the southern English Coast. We kicked steps up the 50° snow of the southwest face then followed the west ridge, a knife edge arête of crumbling snow, to the top. The sharp summit can be occupied by only one person at a time. During the last 10 days of January various members of the expedition made second ascents of Mounts Becker, Berger, Boyer and Matheson in the Merrick Mountains and Mounts Hirman and Neuner in the Behrendt Mountains. These peaks were first climbed in December 1965 by members of a University of Wisconsin party led by Laudon. On November 26 Boyles, Rowley and I reached Cape Zumberge on the edge of the Filchner Ice Shelf; the first time the Antarctic coastline has been attained in this sector (76° S. Latitude, 70° W. Longitude).