Starting across the river in Lestrygonians, Bloom
notices a ball of smoke rising up beside the stone railings of
the bridge: "As he set foot on O’Connell bridge a puffball
of smoke plumed up from the parapet. Brewery barge with
export stout. England. Sea air sours it, I heard." The
barge going under the bridge is from the Guinness brewery stores on
the south bank of the Liffey at the western end of Dublin.
It is carrying barrels of stout down to the mouth of the
river, where they will be loaded onto oceangoing ships that
cannot pass upstream beyond the O'Connell Bridge.
In 1904 these barges were powered by steam, which meant that
they produced large quantities of dirty smoke. In his Ulysses
Guide Robert Nicholson observes that the discrete "ball"
of smoke can be accounted for by an inventive feature of the
barges: "The brewery barges, plying to and from the Guinness
brewery, had hinged funnels which were let down when they
passed under a low bridge, releasing the 'puffball'" (152).