Using Verniers as Verniers, and to make a lathe 5 times more accurate... 

Most people don't know a Vernier can be used in four different ways, internal, external, depth and step. This video explains the fundamentals of the Vernier scale, how to use a Vernier and how Verniers can be used as digital readouts. The Vernier scale can also be used to improve the accuracy of a lathe by as much as 5 times.
Check out www.adendorff.... for there wide range of Verniers...