| Show MOVED IN THE ICE AGE huffe Bowl dars carried all th wr ron canada to kentucky prof A R wallace states in the fortnightly review that an immense area of the northeastern states extend ing south to new york and then westward in an irregular line to cincinnati and st louis is almost wholly covered with a deposit of drift material in which rocks of various sizes are im bedded while other rocks often of enormous size lie upon the surface these blocks have been carefully studied by the american geologists and they present us with some very in facts not only are the distances from which they have been transported very great but in very many cases they are found at greater elevation than alie place from which they must have come prof G F wright found an enormous accumulation of boulders bowl ders on n sandstone plateau in monroe county pa many of these boulders bowl ders were granite and must have come either from the adirondack mountains two hundred miles north or from the canadian highlands still further away this accumulation of boulders bowl ders was seventy or eighty feet high and it extended many miles descending into a deep valley one thousand feet below the plateau in a nearly continuous line forming part of the southern moraine of the great american ice sheet on the kentucky hills about twelve miles south of cincinnati conglomerate boulders bowl ders containing pebbles of red jasper can be traced to a limited outcrop of the same rock in canada to the north of lake huron more than six hundred miles distant and similar boulders bowl ders have been found at intervals over alie whole intervening country in both these cases the blocks must have passed over intervening valleys and hills the latter as high or nearly as high as the source whence the rocks were derived even more remarkable are numerous boulders bowl ders of heldenberg helderberg Hel derberg limestone on the summit of the blue ridge in pennsylvania which must have been brought from ledges at least five hundred feet lower than the places upon which they now lie the blue ridge itself shows remarkable signs of glacial abrasion in a well defined shoulder marking the southern limit of the ice as indicated also by heaps of drift and errati cs so that mr wright concludes that several hundred feet of the ridge have been worn away by the ice the crowning example of boulder bowlder transportation is however afforded by the blocks of light gray gneiss discovered by prof nitch cock on the summit of mount washington over six thousand feet above sea level and identified with bethlehem gneiss whose nearest crop is in jefferson several miles to the northwest and three thousand or four thousand feet lower than mount washington |
