Dorothy Marshall is the only authority that I am aware of who has made a generalised comment about the diameter of the balls i.e. “ about “ 70mm , although there are dozen that are about 20-40% bigger and others that are non- spherical /oval.
Murdo Macdonald ,a Thomist suggested that the figure should be adjusted to “about 69.11mm “ , this suggestion was not due to his access to measurements of the balls and was merely one that suited his agenda . They are ”much the same size” which is not an accurate measure .What is striking about them is that they fit comfortably into the hand and this is likely to be the common factor in their diameter .
There are at least 411 CSB’s but the number of cup marks is in the many thousands and whilst there is an average size there is also a great variety in the diameters and not graded to according to multiples of any dimension . Even within panels the diameters vary . Problems include , how you measure the diameter ,where the edge is for one measurer will differ from that of another ; cup marks are not always perfectly circular they can be even be oval shaped ; lamination , degradation of the surface will not provide an accurate measure of the original diameter .
Cup marks are found the world over and generally have much the same dimensions as those found in the UK , whatever the reason for the similarity of dimensions , a common metrology is unlikely to be the explanation .
Reply | with quote | Posted by tiompan 16th October 2016ce 19:44 |
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