In i839, Agassiz went to the glaciers on tl1e apron of the Matterhorn, the glaciers under the Eiger and the Jungfrau. He walked up the Aar Glacier to the base of the Finsteraarhorn, the highest peak in the Bernese Oberland. “There I ascertained the most important fact that I now know concerning the advance of glaciers,” he wrote later. From a message in a bottle in a cabin on the ice, he had learned that the monk who built the place in i827 had returned nine years later to find it more than two thousand feet down the mountain. Agassiz established his own shelter on tl1e Aar Glacier. He and his colleagues drove stakes into the ice-a row of them straight across the glacier-and before long discovered that glacier ice, like a river, flows more rapidly in the center and also tends to speed up toward the co-working space rotterdam outsides of bends. Diverting a meltwater stream that was pouring into a deep hole in the ice, he set up a sturdy tripod at the surface and had himself lowered into the glacier. He was twenty fathoms down in a banded sapphire world when his feet touched water and he shouted instructions that his descent be stopped. His colleagues on the glacier misinterpreted his cry and lowered him into the water. The next shout was different and was clearly understood. The dripping Agassiz was raised toward the surface among stalactites of Damoclean ice, so big that had they broken they would have killed him. Concluding the experiment, he said, “Unless induced by some powerful scientific motive, I should advise anyone to follow my example.” The better to see the co-working space utrecht alpinevalley ice in its regional perspective, Agassiz and his team climbed mountains-they climbed the Jungfrau, the Schreckhorn, the Finsteraarhorn-and made their observations from the summits, completely unmindful atop a number of the mountains that no one had been there before. Agassiz went to England, Scotland, Ireland, and Wales, looking for the tracks of glaciers. He found them in England, Scotland, Ireland, and Wales. As in Switzerland, he saw roches nwutonnees-humps of exposed bedrock that were characteristically smooth on the side from which the ice had arrived, and plucked and shattered on the other. “The surface of Europe, adorned before by a tropical vegetation and inhabited by troops of large elephants, enormous hippopotami, and gigantic carnivora, was suddenly buried under a vast mantle of ice, covering alike plains, lakes, seas, and plateaus,” he wrote in his Etudes sur les Glaciers (1840).