The Appalachian Mountain uplift, which, roughly speaking, embraces all the ranges constituting the eastern rib of the continent, may be considered to include also the very ancient peneplains of New England. These tumbled hills and shallow valleys, accented here and there by ranges and monadnocks, by which the geologist means solitary peaks, are all that the frosts and rains of very many millions of years and the glaciers of more recent geologic times have left of what once must have been a towering mountain region crested in snow. The wrinkling of the earth's surface which produced this range occurred during the Devonian period when fishes were the predominant inhabitants of the earth, many millions of years before birds or even reptiles appeared. Its rise was accompanied by volcanic disturbances, whose evidences are abundant on islands between the mouth of the Penobscot and Mount Desert Island, though not within the park. The mind cannot conceive the lapse of time which has reduced this range, at an erosional speed no greater than to-day's, to its present level. During this process the coast line was also slowly sinking, changing valleys into estuaries and land-encircled bays. The coast of Maine is an eloquent chapter in the continent's ancient history, and the Lafayette National Park is one of the most dramatic paragraphs in the chapter. Where the Penobscot River reaches the sea, and for forty miles east, the sinking continental shore has deeply indented the coast line with a network of broad, twisting bays, enclosing many islands. The largest and finest of these is Mount Desert Island, for many years celebrated for its romantic beauty. Upon its northeast shore, facing Frenchman's Bay, is the resort town of Bar Harbor; other resorts dot its shores on every side. The island has a large summer population drawn from all parts of the country. Besides its hotels, there are many fine summer homes. [Illustration: IN LAFAYETTE NATIONAL PARK Echo Lake in the foreground, Sommes Harbor beyond Acadia] [Illustration: SEA CAVES IN THE GRANITE Thus does the ocean everlastingly undermine the foundations of the mountains. Photograph taken at low tide; Lafayette National Park] The feature which especially distinguishes Mount Desert Island from other islands, in fact from the entire Atlantic coast, is a group of granitic mountains which rise abruptly from the sea. They were once towering monsters, perhaps only one, unquestionably the loftiest for many miles around. They are the sole remainders upon the present coast line of a great former range. They are composed almost wholly of granite, worn down by the ages, but massive enough still to resist the agencies which wiped away their comrades. They rise a thousand feet or more, grim, rounded, cleft with winding valleys and deep passes, divided in places by estuaries of the sea, holding in their hollows many charming lakes.