Page:Popular Science Monthly Volume 40.djvu/355

Rh 6,000 tons. If allowance be made for an immense fragment which has fallen from its northeast side, the dimensions and cubic contents of "Sheegan" would approximate more closely to those of the Madison bowlder. One point that goes far toward substantiating the claim on behalf of the "Sheegan" rock that it is a true bowlder, is the number of undoubted bowlders of an immense size and of the same granite which exist in comparative proximity. One, about a mile northwesterly, measures 21 feet high, 25 feet long, and 25 feet thick. Another, some three miles southeasterly, and but a short distance west of the Waterford station, on the New London and Northern Railroad (Fig. 2), and whose existence has



heretofore been only locally recognized, has almost the same dimensions; with the added peculiarity of a cavity, or rather tunnel, at its base, some five feet or more at the entrance, and extending with diminishing dimensions completely through the whole mass of the rock, which is about 25 feet in thickness. This cavity, which is somewhat imperfectly shown in the accompanying picture, is of such capacity that it has been fitted up with a cooking-stove, and has served a tramp family as a summer residence.

But one of the most curious and instructive examples of the disruptive and motor power of moving ice during the Glacial period to which attention has ever been called, occurs on the line of the New London and New Haven or "Shore Line" Railroad, about midway between Guilford and Leet's Island stations, and about a mile and a half from either place. Here, on the top of a narrow ledge of rock, which might almost be characterized as a pinnacle, rising (nearly perpendicularly from a salt marsh, or swamp, on one side) to a height of about GO feet, rests a rectangular,