pression made upon him led to a mission for converting the natives
of Britain, which set out from Rome under St. Augustine in 596. Thus
does the column of the infamous usurper Phocas link itself on the
historic page with the conversion of Britain to Christianity.

Beside the Pillar of Phocas are two large marble screens or parapets,
with magnificent bas-reliefs sculptured on both sides. They were
discovered about sixteen years ago _in situ_, and are among the most
interesting and important objects that have been brought to light by
the recent excavations in the Forum. Their peculiar form has given
rise to much controversy; some antiquarians regarding them as an
avenue along which voters went up to the poll at the popular elections
of consuls, designed either to preserve the voters from the pressure
of the mob, or to prevent any but properly qualified persons from
getting admission; while others believe that the passage between the
double screen led to an altar. This latter opinion seems the more
plausible one, for the sculptures on one side represent the
_suovetaurilia_--a bull, a ram, and a boar, adorned with ribbons and
vittae, walking in file, which were usually sacrificed for the
purification of Rome at the Lustrum, as the census taken every five
years was called. The other sculptures on the marble screens consist
of a number of human figures in greater or less relief; one of them
being supposed to commemorate the provision made by Trajan for the
children of poor or deceased citizens in the orphanage which he was
the first to found in Rome; and the other, the burning of the deeds
which contained the evidence of the public debt of the Roman citizens,
which the emperor generously cancelled. But the chief significance of
the sculptures lies in their background of architectural and other
objects indicating the locality of the scenes represented. They place
before us a view of the Forum as it appeared in the time of Trajan,
and enable us to identify the various objects which then crowded it,
and to fix their relative position. The topographical importance of
these reliefs has been well discussed by Signor Brizio and Professor
Henzen in the _Proceedings of the Roman Archaeological Institute_; and
also in a paper read by Mr. Nichols before the Society of Antiquaries
in London in 1875. By translating into perspective their somewhat
conventional representations of temples, basilicas, and arches, Mr.
Nichols has given us in h