Sir,
It is a good thing that Dr Colhoun has reminded us that as early as 1905-08 J. R. Kilroe interpreted an ice-wedge pseudomorph observed near Londonderry as having been formed when the sands and gravels that it cuts were frozen (Reference Colhoun,Colhoun, 1970).
Dr Colhoun has noted that Kilroe’s interpretation pre-dated “the classic interpretation of ground-ice wedges in Alaska published by (Reference Leffingwell,Leffingwell 1915, Reference Leffingwell,1919)”, which is true. But Leffingwell was by no means the first author to give the proper interpretation. Ice-wedges were first described from East Siberia by Reference Adams,Adams (1815) and Reference Middendorff,Middendorff (1867), and correctly interpreted by von Reference Bunge,Bunge (1884) on the basis of extremely careful field observations. This has been stressed by Reference Troll,Troll (1944) and myself (Reference Cailleux, and Taylor,Cailleux and Taylor, 1954).