The British National Archives also have two records for Wormwood scrubs which can be ordered online.

http://www.nationalarchives.gov.uk/catalogue/RdLeaflet.asp?sLeafletID=120&j=1#Section2

A "Separate confinement register" of prisons from 1882-1886 and a "Prisoner working parties" list from 1874 - 1890.

By the way, were his parents William Vaughan & Elizabeth Charles?
BP.