Also, the stones have been damaged and eroded over the years, and so it is impossible to know exactly their original shape. A review of the way that the stones were measured by Lothrop reveals that claims of precision are due to misinterpretations of the methods used in their measurement. Although Lothrop published tables of ball diameters with figures to three decimal places, these figures were actually averages of measurements taken with tapes that were nowhere near that precise.[19]