For the record Thomas and Whitelaw got their viscountcies in 1983, and the title of Earl of Stockton was created for Harold Macmillan in 1984 = all hereditary. The first two came after many years in which no hereditary titles were conferred and were seen at the time by some commenntators as a manoevre by Margaret Thatcher to pave the way for a baronetcy for her husband (which would subsequently pass to her worthless son Mark). Denis Thatcher duly got his baronetcy and Mark duly inherited the title.

All this is now irrelevant in terms of House of Lords membership. Legislation passed in 1999 when the hereditaries were reduced to 92, ensured that inherited titles would not qualify for sitting in or voting in the House of Lords.