On an outcrop of volcanic bedrock near the paath sit half a dozen erratic boulders, some weighining as much as twenty tons, of a coarse-grainned pink granite. Once, I chipped off a sample of)f the rock and followed the bedrock scratches northth, looking for the source. Like an Indian trail of bent twigs. le scratches led me several miles out of Easton into the town of Stoughton, where I found what I was looking for, a south-facing ledge of bedrock that under the hand magnifier was identical to the erratics. It is well known that glaciers "pluck" boulders from the downstream side of the rocky outcrops they move across (all of New England's ragged ledges are on the south sides of hills), so I was sure I had found my source. And that's where I stopped. But the trail goes on. The scratches lead orth from Stoughton, through the western suburbs of Boston, up the valley of the Merrimack River, veering slightly westward near Concord, New Hampshire, toward the Connecticut River, where they pass into Vermont, and on into Canada.
It is possible to find bits of glacial drift in Easton that had their origin anywhere along the line of scratches. Pieces of New Hampshire, Vermont, and Quebec litter the ground beneath my feet. The trail of scratched rock leads south, too, out of Easton, ^ through Wareham, under Buzzards Bay and Vineyard Sound (which, of course, were not submerged when so much water lay frozen upon the land), to Martha's Vineyard, the southern terminus of the glacier, where even today one might find a scrap of our North Easton bedrock carried there by moving ice.