Unfortunately the visit was a family one,"C'mon, dad, lets go! and I have not been able to visit Vinalhaven again to make sure I got the details exactly right. But think for a minute what it takes to work with chunks of stone that size- largely by hand- without modern technology and machinery... let alone imagining, designing and building a lathe to work with material that large and heavy. For reference, granite weighs about 175 lbs per cu. ft. An incredible achievement.
More of the story and details of the lathe at Vintagemachinery.org.
I'd like to thank Vector Warbirds for his contributions to this post.