Simon Dedalus remarks on "The O'Connell circle," while Jack Power sends his gaze "up to the apex of the lofty cone." Daniel O'Connell's body (sans heart) has been buried in two different places: for the first two decades in a raised circle of earth near the center of the Glasnevin cemetery, and afterwards in a tower near the mortuary chapel on the edge of the cemetery.
Since these two sites are not adjacent, it seems possible that Joyce made a mistake in having two characters refer to them as if they are. Another possibility is that Dedalus may be referring to the grounds around the tower, rather than to the raised circle in the center of the cemetery. As the last of the photos here shows, the tower is surrounded by a circular patch of turf, with a circular path at its circumference. Perhaps this is what Dedalus calls the "The O'Connell circle"?
In 1869 O'Connell's remains were moved from the raised circle at the center of the cemetery to a crypt at the base of a 168-foot monument, modeled on medieval Irish round towers, that had been under construction since 1855. Such glorification befits this champion of Catholic rights who worked to establish a cemetery in which Catholics and Protestants alike could be buried with the full rites of their respective faiths.
The tower originally housed spiral stairs allowing visitors to climb to the top, but it was bombed by loyalists in 1971, perhaps in reprisal for the 1966 bombing of Nelson's pillar by the IRA. The three-foot-thick granite walls of the tower survived, but the staircase was destroyed. The Glasnevin Trust has raised funds and received permission to rebuild the stairs, in a double helix pattern that will allow people to pass both up and down without difficulty. Since Glasnevin itself sits at 110 feet above sea level, the view from another 150 feet up promises to be spectacular.