O'Brien was adjudged guilty of high treason, causing a by-election.
Monsell was appointed President of the Board of Health, requiring a by-election.
Monsell was appointed Vice-President of the Board of Trade, requiring a by-election.
Monsell was appointed Postmaster General of the United Kingdom, requiring a by-election.
Monsell was created a peer in January 1874, voiding his seat, and a writ was to be issued for a by-election.