Scrambles Amongst the Alps in the Years 1860–69 · Chapter
The Valley of Aosta, and Ascent of the Grandes Jorasses explained
Whymper examines the glacial theories of Professors Ramsay and Tyndall regarding the excavation of Alpine valleys, using the Valley of Aosta as a case study.
What happens
Whymper examines the glacial theories of Professors Ramsay and Tyndall regarding the excavation of Alpine valleys, using the Valley of Aosta as a case study. He argues that the evidence from roches moutonnées, the mouths of valleys, and the inability of glaciers to remove loose river-gravel at Ivrea demonstrates that glaciers have only slightly modified pre-existing valley forms, not excavated them. The chapter includes a detailed critique of both theories and concludes that glaciers have extremely limited power for excavation.
Themes in this chapter
Scientific Observation
Whymper meticulously analyzes glacial striations, roches moutonnées, and valley contours to argue against the excavation theories of Ramsay and Tyndall, demonstrating a commitment to empirical evidence.
Human vs. Nature
The chapter explores the power of glaciers as natural forces and the limits of their ability to reshape the landscape, contrasting human theories with the stubborn evidence of the rocks.
Characters to notice
- Professor Ramsay
Whymper critiques Ramsay's theory that glaciers excavated lake-basins and valleys, citing Ramsay's own admission that the glacier at Ivrea failed to remove loose river-gravel.
- Professor Tyndall
Whymper examines Tyndall's theory that glacier motion and differential erosion of hard and soft rocks produced valley inequalities, but argues that the evidence contradicts Tyndall's conclusions.
- Edward Whymper
Whymper presents his own observations and reasoning, arguing that the Valley of Aosta and other Alpine valleys were not excavated by glaciers but only slightly modified.
Key passages
“that the glaciers of the Alps were competent to scoop out the valleys of the Alps,” 284 and I am unaware that his opinions have undergone any alteration since that time.”
Whymper notes that Professor Ramsay still maintains that Alpine glaciers could have carved out the valleys.
Whymper introduces Ramsay's theory as a starting point for his critique.
“It is impossible to criticise these two theories at the same moment. Both of them agree in attributing enormous powers of excavation to glaciers, but they disagree totally and completely as to the modus operandi by which the effects were produced.”
Whymper points out that while Ramsay and Tyndall both believe glaciers are powerful excavators, they fundamentally disagree on how the excavation happens.
Whymper highlights the contradiction between the two prominent glacial theories.
“The evidence from the mouths of the valleys of the Alps is not less hostile to Dr. Tyndall’s theory.”
Whymper argues that the shape and features at the lower ends of valleys contradict Tyndall's ideas about glacial erosion.
Whymper uses the valley mouths as key evidence against Tyndall.
“No better proof could be required that in great part the valleys of the Alps were approximately as deep before the glacial epoch as they are at present; and I believe, with the Italian geologists, that all that the glaciers as a whole effected was only slightly to deepen these valleys.”
Whymper quotes Gastaldi's conclusion that Alpine valleys were nearly as deep before the Ice Age, and that glaciers only deepened them a little.
Whymper endorses the view that glaciers had a minor role in valley formation.