Norman Muller writes in:
The Ekonk "petroglyphs" are only one part of the story. That entire area of CT and RI seems to have a type of stone with iron oxide veins that promote the development of circular or figure-8 "petroglyphs." There are some on the Miner Farm (see above, particularly the boulder with the figure 8 on the side), and also on the Yawgoog Scout Reservation, such as Millenium Rock. Jim says geologists have looked at this and have said they are manmade, but these geologists need to be re-educated. Also, the channels are too narrow and deep to have been made with stone tools. I have an article somewhere by Bednarik, an Australian rock art expert, who described xenoliths, and then showed an image of a circular one that looked exactly like the ones on the Miner Farm.