still be seen perfectly distinct after all these centuries, and
vividly recall the terrible associations of the incident. The dislike
which Caracalla and Geta had for each other was so virulent that their
father took them both with him to Britain, in order that they might
forget their mutual animosity while engaged in active warfare.
Septimius Severus died during this campaign at York, and his sons
returned to Rome to work out soon after the domestic tragedy of which
this Arch reminds us. On the top of the Arch there was originally a
bronze group of a chariot and four horses, with the emperor and his
sons driving it. But this was removed at an early date; and in the
middle ages the summit of the Arch supported the campanile of the
church of St. Sergius and Bacchus that was built up against its sides.
A little to the left, the road passing under the Arch joins the Clivus
Capitolinus which wound through the Forum, and led up to the great
Temple of Jupiter on the Capitol. The pavement of this ancient road,
which still exists, is formed of broad hexagonal slabs of lava, and is
as smooth and as finely jointed at this day as when the triumphal
processions of the victorious Roman generals used to pass over it.

At the western corner of the Arch of Severus are the scanty remains of
a tall conical pyramid, about fifteen feet in diameter, which is
identified as the Umbilicus Romae, placed in the exact centre of old
Rome. Not far from it stood the Milliarium Aureum, or Golden
Milestone, on which were inscribed all the distances of roads without
the walls. The Roman roads throughout the empire terminated at this
point. With this central milestone was connected that admirable system
of roads which the Romans constructed in our distant island; and it is
a remarkable circumstance that the principal railway lines in England
are identical with the general direction of the old Roman roads. The
Antonine Way is now the Great Western Railway, and the Roman Watling
Street, which ran diagonally across the country from Chester in the
north-west to Dover in the south-east, is now replaced by the Dover,
London, Birmingham, Grand Junction, Chester, and Crewe Railways. The
reason of this union of ancient and modern lines of communication is
obvious. The Romans formed their roads for the purpose of transporting
their armies from place to place, and at certain distances along the
roads a series of military stations were established. In course of
t