Outwash from Icelandic glacier, May 2010 (Stromboli online).
Outwash from Icelandic glacier, May 2010 (Stromboli online).
The diagram at left, from AN Strahler’s Physical Geography, shows many of the geological features that Agassiz saw. Other explanations for many of these features did not survive testing, but the glacial idea has gained support worldwide at explaining things and demonstrating that the whole earth’s surface was substantially cooler in the geological past.