After six relatively placid chapters (Nestor has shouting schoolboys, Hades some clattering horsedrawn carriages), Aeolus plunges the reader into the "heart" of an urban "metropolis": lower Sackville Street and adjoining thoroughfares, where dozens of "clanging" trams are noisily converging and departing, clanking presses are churning out miles of newsprint, mail cars are lining up before the General Post Office to receive flung sacks of mail, barrels of porter are "dullthudding" out of a warehouse and rolling onto a barge, a conductor is shouting out directions, bootblacks are drumming up business. In this cacophonous bustle, two impressions compete: Ireland does have a city to rival other great European capitals; but far from being purely "Hibernian" (i.e., Irish) this is a conspicuously imperial capital.
Joyce begins his cameo portrait of the metropolis with the urban tram system that in 1904 was a source of great civic pride. Over the preceding three decades tramlines had been laid throughout greater Dublin, and by 1901 all the lines were electrified and sported a fleet of mostly double-decker electric trams. Bloom's repeated musings about the benefits of running "a tramline from the parkgate to the quays" with cattle "trucks" to avoid having to drive the animals through the streets, and running a "line out to the cemetery gates" with "municipal funeral trams like they have in Milan" (Hades) reflects the spirit of civic improvement with which Dubliners greeted an urban transportation system that in 1904 was perhaps the best in Europe.
In Dublin in Bloomtime, Cyril Pearl quotes Tom Kettle, "the brilliant young writer who was killed in World War I," to the effect that "The tramcar is the social confessional of Dublin. Sixpence prudently spent on fares will provide you with a liberal education" (17-18). That sense of expansive cosmopolitan communication appears in Joyce's next vignette, the activity surrounding "the general post office." The letters, cards, and parcels in the flung sacks are bound "for local, provincial, British and overseas delivery," and delivery to Britain, at least, was quite swift. Twice a day mailboats promptly left the enclosed harbor at Kingstown bound for Holyhead in Wales, after receiving mail delivered by express trains from Dublin. Other trains quickly shuttled the mail from Holyhead to London.
But as the title of that second section, "THE WEARER OF THE CROWN," proclaims, the "mailcars" were the property of "His Majesty," "E.R.," Rex Edward VII, and every part of the efficient system from "North Prince's street" to Kingstown harbor existed to facilitate communication between the two imperial capitals of Dublin and London. "Nelson's pillar," an immense granite Doric column topped with a heroic statue of Britain's most brilliantly successful naval leader, was erected in Dublin in 1808, 35 years before the British got around to building a similar one in Trafalgar Square in London. Dublin has always been an imperial city (it was founded by Vikings), and in the paragraphs that begin Aeolus one can hear Joyce's recognition of the tension between aspiring to be one of the great cities of Europe and knowing that it is one of the key cities in the British empire.