There was a chockstone there, in a square chimney marked by bright greenish-yellow lichen. Instead of tackling the chimney, Charles assaulted a vertical 40-foot cliff to its right, working his way up bit by bit on what he claimed were plentiful holds. From my vantage point several hundred feet below, the cliff seemed to be overhanging, and I waited for a scream, clattering rock, and a grim thud. Instead I heard a yell of triumph, and there was Charles on the summit plateau at the top of the cliff. I scrambled up toward him and he offered to belay me up the chimney. The chockstone overhung a little bit and forced me out onto a smooth wall to the left, but with a top rope it was great fun. Although the exposure wasn't bad, I would call the chimney class four because of the awkward climbing on small holds. I would climb it unroped on a good day, but I wouldn't like to downclimb it unroped. A fall, while not fatal, would slam you onto some nasty sharp blocks.
So that's the mystery of Mendel's east face -- just head for the square chimney on the upper left with the greenish-yellow lichen, and bring a short rope (50' is plenty).