Moving large boulders

From Norman Muller:
I visited a very impressive lace wall site in Ashfield, MA , a couple of weekends ago, where Jim Vieira guided me to it.  The wall is more or less oriented north-south and follows a stream downhill.  The wall is tied in with outcrops and large boulders, which is the main reason I wanted to see this feature.  I was not disappointed.  Along the entire length of the wall are huge boulders, some I estimate to weigh a thousand pounds or more (see attachment).  Curt, in his report on the Killingworth site in CT, concluded that some large boulders/rocks at that site were probably moved into place after the colonial period, since it is not known that Indians were capable of moving large boulders without the aid of draft animals.  I pointed out that similar large boulders have been found at the Rochester site in Vermont (see next attachment), a site where the cairns now present preexisted before the land began to be developed in the early 1800s.  Curt found my research well done, but he didn’t make any direct comment that the Indians probably were able to move large stones before the introduction of draft animals. 

I pointed out other examples, such as one boulder in a wall in Georgia (3^rd attachment), accepted by archaeologists to be an Indian wall, but again he didn’t address this directly.  So, have you ever wondered where exceptionally large stones in cairns and walls might have come from, and how they were transported to the construction site?   These are questions that few address.