Mount Index, Middle-Main Peak Gully. On January 20, Fred Dunham and I climbed the gully between the Middle and Main Peaks of Mount Index from Lake Serene, south of the South Norwegian Buttress. The climb consisted of several steep steps separated by lower-angled snow-and-ice slopes. The crux of the climb was a seventy-foot vertical and overhanging waterfall about halfway up. We left the town of Index at six A.M. in cold, clear weather and reached the summit of the main peak at 11:30 P.M. in a snow storm. As in every winter gully climb, conditions must be just right. By the time we were descending the east route to Lake Serene, our gully was being raked by avalanches of new snow.