The following are the correct ceremonious modes of addressing and
beginning letters to persons of title or holding offices:
AMBASSADOR, BRITISH--Address: 'His Excellency [in other respects according
to his rank], H.B.M.'s Ambassador and Plenipotentiary.' Begin: 'Sir,' 'My
Lord,' &c., according to rank. Refer personally to as 'Your Excellency.' An
Ambassador's wife, when resident abroad, is sometimes, but not very
correctly, designated 'Your Excellency.'
ARCHBISHOP--'His Grace the Lord Archbishop of ----.' Begin: 'My Lord
Archbishop.' Refer to as 'Your Grace.' In formal documents the Archbishop
of Canterbury is addressed as 'The Most Reverend Father in God, Frederick,
by Divine Providence Lord Archbishop of Canterbury, Primate of all England
and Metropolitan;' the Archbishop of York as 'The Most Reverend Father in
God, William, by Divine permission Lord Archbishop of York, Primate of
England and Metropolitan.' But an Irish Archbishop appointed since 1868 is
only 'The Most Reverend the Archbishop of ----,' unless he happen to be a
temporal peer, in which case he is 'The Right Hon. and Most Rev.'