The controversy centers on the manner in which the ice sheet receded from Connecticut. The earliest ideas envisioned the ice retreat-ing north in stages, an icy blanket pulled off a shivering land by a teasing climate. Flint, in contrast, thought the glacier melted away right where it lay in big lumps of stagnant, "dead" ice. The newest evidence suggests that the true story is a cross between a retreating ice blanket and Flint's stagnant lumps. This theory, called "stagnation-zone retreat,") pictures the glacier retreating north with a narrow fringe of stagnant ice. But although Flint's interpretations have now come under question, his map has been the firm base upon which all subsequent work on Connecticut's glacial history has been built.

The Push for More Detail

During the hundred or so years that followed Percival's pioneering survey, the store of geologic knowledge about Connecticut built up slowly. The main contributions during these years were Flint's map of the glacial geology, better dating of the rocks, and some improvements in the detail and accuracy of bedrock mapping. This work was carried out primarily by geologists from the University of Connecticut, Yale University, Wesleyan University, Trinity College, the United States Geological Survey, and the Connecticut Geological and Natural History Survey. But for the most part, the geologists who lived in Connecticut were more concerned with helping to complete the reconnaissance mapping of the rest of the world.

The lack of adequate topographic maps contributed to the slow advance in mapping detail. Geologic mapping depends on accurate maps of the land surface so a geologist may record the proper location of every observation. In addition, the contour lines on a topographic map are an invaluable aid in interpreting how the "dots" connect, for the shape of the land usually reflects the underlying geology. During the 1940s and 1950s, a new series of maps expressed the topography of the state with Hotfoot contour intervals, showing the shape of the land in greater detail

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