Mt. Tyndall from Mt. Williamson. Note the two lakes. The lower lake, at 3713 m. is completely clear of ice, the upper lake, at 3733 m., has a skin of ice across almost it's entire surface. Out of frame to the left is Lake Helen of Troy (3816 m.), which was entirely socked in with snow and ice. Interesting the effect that 100 m. of elevation and a couple fewer hours of direct sunshine will have.