ec. 23. We have seen, however, that, even in the earliest days, there was
a tendency to admit additions to the simple longitudinal plan, which, in
process of time, were bound to give birth, if not to a definitely
centralised plan, to something, at any rate, in which a central point
counted for much. A feature of the early cathedral and of St Pancras at
Canterbury, was the projection of _porticus_, porches or side chapels,
from the nave. These were entered by archways pierced in the centre of
the lateral walls. In the cathedral they had outer doorways, and formed
the main entrances of the church, on the north from the monastery, on
the south from the city. The south porch contained the altar of St
Gregory, and, as Eadmer tells us, was used as a court of justice to
which litigants, in process of time, resorted from every part of
England. In the north porch, dedicated to St Martin, was held the school
of the monastery. Upon both porches towers were built at a date which
cannot be ascertained, but was probably later than the time of
Augustine. Of the use of the porches at St Pancras, which did not
contain outer doorways, it is impossible to say anything definitely.
Entrance porches, of which one remains, projected from the sides of the
church at Bradford-on-Avon: the outer and inner doorways of the north
porch are extremely narrow, and are placed west of the centre of its
north and south walls. It is possible, therefore, that there was an
altar in this porch, so that it served the double purpose of entrance
porch and side chapel.

Sec. 24. As time went on, the western porch beneath the tower was disused
as a public entrance. The principal entrance of most churches is on the
south side, west of the centre of the aisle wall, and is usually covered
by a porch. There is a Saxon example of this at Bishopstone in Sussex,
where, as at Bradford, room seems to have been left for an altar on the
east side. However, the main entrance of the ordinary Saxon church was
at the west end, through the ground floor of the tower. The porch in the
lateral wall seems to have been regarded primarily as a side chapel; and
in some later Saxon churches the porches were dissociated from lateral
doorways, and were planned as closed projections from the eastern part
of the north and south walls of the nave. This seems to have happened at
Britford, near Salisbury, where archways remain on both sides near the
east end of the nave. At Deerhurst square proj