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357 Lake Winnebago

to portions of the western shore, but with less continuity than is observed on the east shore. The wall generally rises about five feet above, and extends into the lake under the water for some hundreds of feet. Above the wall on the east side there immediately succeeds a table of excellent land covered with a growth of heavy timber; and still further back, the ground rises into a high ridge, in which limestone and sandstone are found in great abundance. On approaching the southern extremity of the lake, however, the stone and timber disappear, and the land becomes a rich grassy prairie, coming [down] quite to the water's edge." The wall above described probably owes its origin to the expansive force of the ice in winter by which the rocks in the shallow water near shore are annually moved towards the shore until they are finally thrown up into a ridge or wall, as is seen on the Pewaukee and other lakes, in Milwaukee County. There is a small

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