Over at Ponkapoag Pond, which is perhaps a hundred thousand years older, the effect of this pushing ice through the ages, working at various levels, has been to produce mounds and dikes almost beyond belief. Moreover, these are placed in such situations that it is plain to see that the water was for the greater part of that long time some feet higher than now. In my first acquaintance with these ridges I thought them dikes raised by modern men, early farmers, perhaps, who thus for some occult reason banked the pond as they surrounded their fields with the stone fences which last still. No man of to-day, however ardent a farmer, builds these great barriers between field and field. Yet even with the stone walls before the eye it is hard to believe that men built dykes along the pond shore that averaged a hundred feet across and were in some places much more. A ten-foot bank would do, and it was hard to believe that so much labor would be willingly wasted. Yet along the Ponkapoag Pond shore in one place is a barrier many feet high and broad built, not of sand, but of the rough slate rock of the region, thrown together loosely in huge rough blocks and tamped with earth. This is so much bigger than any of the field-enclosing stone walls that it puts the modern farmer quite out of the question, and on finding it I had pleasant dreams of a prehistoric race of mound-builders who might have preceded the Indians in their occupation of the land and have built these pond embankments for purposes of their own. Again my scientific friend disapproves my dream theory in well-chosen argument that is very convincing--to him. Nevertheless I go my way with mind equally divided,--between theories as to prehistoric men-mound-builders and the probabilities of the work having been done by that great beaver which, according to the Algonquin legend, made the world out of mud brought up from the bottom of a lake. Mind you, I am quite convinced that it is the ice which is doing this on the Reservoir shore, but Ponkapoag--that is far enough away to be in the land of legend and all sorts of wonderful things may have happened on its borders.