Gletschergarten Luzern · Denkmalstrasse 4 · CH-6006 Luzern · Tel. 041 410 43 40 · info nospam@nospam.nospam gletschergarten.ch

Walk to the observation tower - Artificial "Glacial Mill"

Artificial "Glacial Mill" Bild 135
Artificial "Glacial Mill" Bild 136

This model of a 'glacial mill' from 1896 illustrates the outdated first theory of how potholes were formed. It was believed that big rocks, rotated by meltwater, similar to a flour mill, had ground the holes into the bedrock. 

Contrary to those beliefs, we now know that glacial potholes were formed at the base of a glacier by the force of pressurized meltwater carrying sand and gravel, forming vortices with high speeds. This process can erode large holes within only a few years.

The rock in the model can only be rotated by the low-flowing water because it is hollow and light. The model is being conserved for its value to the history of science.

 

 

 

a-gmuer.net