Page:History of Barrington, Rhode Island (Bicknell).djvu/20

4 down in the carriage of a few miles to Providence. The width of the deposit of the Cumberland iron stones is about eight miles, including both sides of the Bay, Kent and Bristol Counties. The most interesting boulder in Barrington is that which landed on the south end of the grey-wacke ledge at Drownville near the water tank. As this great stone of near an hundred tons is a conglomerate or pudding stone, it may have been lifted from the north end of the ledge on which it stands and carried by the ice to the south end and there deposited, when the glacier melted and receded to its northern home. The gravel bank from Long Swamp to Rumstick and Nayatt Points is a medial moraine, called in common language a "hog-back," and forms an excellent foundation for road-building. Near Boston, this kind of gravel is mixed with a peculiar cement, which makes it an excellent surface dressing for common roads.

As the glacier receded, it left the solid land it had formed and channels for the water, which came in plentiful supplies from the melting ice rivers of the north. On the authority of geologists, our coast line extended into the Atlantic, some forty miles beyond its present bounds, and Block Island was a part of the main land. The site of our famous watering place, Newport, was, at the close of the ice age, as far from the ocean as it is from Boston, and the site of Boston was inland forty miles, so that the ocean was not visible from the summit of the Blue Hills, then supposed to be fifteen hundred feet in height. Since that period, the ocean has washed away all the diluvial deposit or dump, until the Atlantic has reached the rocky barriers of the old rocks which say, "Thus far shalt thou come and no further, and here shall thy proud waves be stayed."

Providence, Barrington, Warren, Palmer's and Taunton Rivers are the deeper channels cut out by the glaciers, into which the waters of the ocean ebb and flow. They are sunken rivers, pouring into salt water the small quantities of fresh water, which flow into them from their tributary streams. Prince's Pond, which in my boyhood used to be