Coronation Day is a drinking song that was sung in
English streets in 1902, during the months of anticipation
leading up to the coronation of King
Edward VII. Mulligan sings it "out of tune with a
cockney accent" in Telemachus, and in Circe
King Edward himself intones it "with soft contentment."
Gifford notes that “coronation day” could
also be “slang for payday because the pay could be reckoned in
crowns (five-shilling pieces).”
Just before this play on crowns, Mulligan has made a similar
play on the name of the one-pound coins called sovereigns,
celebrating the “Four omnipotent sovereigns”
that Stephen will receive from his employer later in the
morning. The power of these sovereigns, he figures, resides in
their ability to procure alcoholic inebriation; hence his
enthusiastic rendition of the drinking song.