Correspondence between John Nye and Stan Evans concerning radio echo sounding of ice Correspondence with Evans at the Scott Polar Institute, discussing the use of radio echo sounding to determine the shape of glacier beds and the problem of wave reflection off curved surfaces causing strong echos on recordings. The folder includes some manuscript notes on the subject, as well as photocopies of notes by others [not in Nye's hand]. Also contains one photographic print of a radio echo recording. 1970