ABSTRACT
THE megalithic character o f many o f the prehistoric monuments in the area now to be reviewed is due to geological factors which must now be considered. North o f the Pewsey Vale, the chalk downs are more or less strewn with the remains o f a Tertiary capping o f sand stone, in the form o f sarsens or greywethers, which by impeding the progress of the plough might have caused more of the field monuments on these downs to survive to the present day, had it not been for the value o f the stone as building material.
