The "smooth silver case" in which Haines carries his cigarettes befits a man who “comes from Oxford,” and the "green stone" that sparkles amid the grey metal, like Ireland in the sea, symbolically suits the Englishman's status as "the seas’ ruler." Haines graciously offers Stephen a cigarette from the case, his noblesse obliging him to share his wealth with the impoverished Irishman next to him, even as he apologizes for the injustices of history.
Joyce's choice of this image as a symbol for British imperial domination of Ireland was probably inspired by a notorious gift that King Henry II of England received in 1155 from Pope Adrian IV, a.k.a. Nicholas Breakspear, the only Englishman ever elevated to the papacy. In the work called Metalogicus, the English cleric and scholar John of Salisbury writes that he delivered to Henry the infamous bull that begins Laudabiliter, giving him temporal rule over Ireland, along with a gold ring containing an emerald stone to signify the overlordship. The history of this exchange (as well as the authenticity of Laudabiliter) is murky and contested, but Joyce scathingly recalls it in Oxen of the Sun: "It is that same bull that was sent to our island by farmer Nicholas, the bravest cattle breeder of them all, with an emerald ring in his nose."
In "Ireland, Island of Saints and Sages," an important
lecture delivered in April 1907 to an Italian audience in
Trieste, Joyce remarked on the imperial whims of the Holy See
and the slavish submission of the Irish: "First, by means
of a papal bull and a ring, it gave Ireland to Henry II
of England, and later, in the papacy of Gregory XIII, when the
Protestant heresy raised its head, it repented having given
faithful Ireland to the English heretics, and to redeem the
error, it named a bastard of the papal court as supreme ruler
of Ireland. He naturally remained a king in partibus
infidelium, but the pope's intention was none the less
courteous because of this. On the other hand, Ireland's
compliance is so complete that it would hardly murmur if
tomorrow the pope, having already turned it over to an
Englishman and an Italian, were to turn their island over to
some hidalgo of the court of Alphonso who found
himself momentarily unemployed, because of some unforseen
complication in Europe" (170).
The green stone from Stephen's first chapter recurs in
several later episodes. In addition to the reference in Oxen,
it seems to return in the face of Bloom's cat in Calypso:
"He watched the dark eyeslits narrowing with greed till her
eyes were green stones." Perhaps the most important
word here is "greed": the cat's hunger seems to draw the
English lust for conquest and colonial exploitation back into
the narrative. In Aeolus, one of the newspaper-like
headlines is "ERIN, GREEN GEM OF THE SILVER SEA."
The narrative content to which this immediately refers is Dan
Dawson's speech in praise of Ireland's natural beauties, but
once again overtones of English conquest sound, because the
chapter soon turns to themes of Irish rebellion and the quest
for independence. These coming themes are adumbrated when
Bloom walks into the newspaper office and hears Ned Lambert
reading Dawson's speech:
— Whose land? Mr Bloom said simply.
— Most pertinent question, the professor said between his chews. With an accent on the whose.