Lake Hitchcock and Clay | |
| About 18,000 years ago, after the glacier age and the Laurentide ice sheet had retreated northward, Lake Hitchcock was formed. The glaciers had eroded rocks into a powder known as glacial flour. Each winter, this material would settle out in the lake and become a layer of clay. Deltas of sand and gravel also formed where streams poured into Lake Hitchcock. Each year, the layers of glacial flour and sand from the deltas would make varves. Varves can be counted like tree rings. The resulting clay was used to make red bricks used in buildings throughout New England and elsewhere. |   |
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