I believe that I was originally responsible for the statement that crevasses in temperate glaciers did not in general exceed 30 m. in depth, although Dr. Orowan, with whom I often discussed the point, no doubt based his views not on my experience but on theoretical grounds. In my paper “The structure of a temperate glacier,” Geographical Journal, Vol. 97, No. 5, 1941, p. 301, I wrote: “I believe the great depths attributed to crevasses in the Alps are mythical. We explored many, and the greatest depth we reached was 30 m.; a crevasse said to be at least 60 m. deep proved to be no more than 25.”

My subsequent observations in the Alps confirmed this assessment, but no doubt there can be exceptions, one of which Dr. Loewe has encountered.

It would be interesting to hear of actual measurements from colder regions than the Alps which could throw further light on Dr. Loewe’s statement that many high ice walls in those regions must be at 0°C.