cial epoch when the ice-sheet was mostly melted away. There can be little doubt that the continuation of Lewis's study of the drift in England, if he had lived, would have soon convinced him of the correctness of the opinions of Searles V. Wood, Jr., Mr. Skertchly, and James Geikie, that land-ice during the earlier Glacial epoch overspread all the area of the Chalky bowlder-clay, extending south to the Thames. Small portions of northern England, however, escaped glaciation both then and during the later cold epoch when the terminal moraines mapped by Lewis were accumulated; and these tracts of the high moorlands in eastern Yorkshire and of the eastern flank of the Pennine chain are similar to the driftless area of southwestern Wisconsin.
"Comparison of the drift in the United States and Great Britain enabled Prof. Lewis to refer the British modified drift, both that often intercalated between deposits of till and that spread upon the surface in knolly and hilly kames and more evenly in plains and along valleys, to deposition from streams supplied by the glacial melting, the material being washed out of the ice-sheet. These beds, however, are to be carefully distinguished from those of interglacial and post-glacial age. It is greatly to be regretted that this sagacious observer was not spared for the fulfillment of his plan of yet more extended study of European glacial deposits in the light of his wide knowledge of the terminal moraine and other drift formations in this country."
Prof. Lewis was a member of the American and the British Associations; of the American Philosophical Society, the Academy of Natural Sciences, and the Franklin Institute, in Philadelphia; of the Geological Society of Liverpool; and a Fellow of the Geological Societies of London and Germany.
He was married in 1883 to a daughter of the late William Parker Foulke, of Philadelphia, who, with a daughter, survives him, and will transfer his unfinished papers, for completion, to the distinguished geologists who have generously offered their assistance. He possessed a strong Christian faith, and was an active member of St. Michael's Protestant Episcopal Church, Philadelphia, of whose Sunday school he was for many years a teacher, and for a long time superintendent. He had the happy faculty of imparting knowledge to those whom he taught, and in making his instructions interesting and agreeable. With a high character, a pure standard of manhood, fine mental and physical powers, a wide range of scholarship, a happy, genial, and enthusiastic temperament, rare perseverance and industry, and a lofty devotion to the interest not only of science but of mankind, his life seemed to promise the widest usefulness and honor.
The following list of Prof. Lewis's published papers is abbreviated from the "American Geologist":
