How did Louis Agassiz and his colleagues study the movement of the Aar Glacier?

To study the movement and structure of the Aar Glacier, Louis Agassiz and his associates established a research station directly on the ice, which they named the "Hôtel des Neuchâtelois".1

By living and working from this hut, they were able to conduct intensive field studies to trace the glacier's activity. Through these observations, Agassiz was able to demonstrate that the movement of the glacier was fastest in its central portion. This research was a foundational component of his broader work on glacier activity, which he published in his 1840 work, Études sur les glaciers.123