her to the west. Possibly it projected into the nave. At
the west end of each of the aisles of the nave a tower was placed, and
between these two towers was the chief public entrance to the church.
From the subsequent history of the structure it would appear that the
two western towers had been built up and finished, so far, at least,
as was necessary to allow of the completion of the nave with its
aisles and roofs. The same may be concluded of the central tower.

This latter probably rose only just above the ridge of the roofs. To
carry it up so far would have been dictated to the builders by
structural reasons; for such a height would be required to help the
stability of the piers and arches below, since they had to resist a
variety of opposed thrusts. But even this tower, low as it no doubt
was, like others of the same date, did not survive the dedication more
than about twenty-six years. The whole building was covered with a
high-pitched wooden roof over the nave, transept, and chancel; and
beneath the outer roof there was a flat inner ceiling of wood formed
between the tie beams, similar to those now to be seen at Peterborough
and S. Albans. The north and south aisles of the nave were protected
by roofs which sloped up from their eaves against the wall that rose
above the nave arcades. Internally the ceiling to these was a simple
groined vault supported by transverse arches.

Immediately above the vault of the aisles was the gallery of the
triforium. This was lighted throughout by small external round-headed
windows, some of which may still be seen embedded in the walls. The
aisles and ambulatory of the chancel were treated by the same methods.
In the triforium gallery, above the transverse arches of the aisles,
were other semicircular arches. These served a double purpose: they
acted as supports to the timber framework of the aisle roofs, and also
as a means of buttressing the upper part of the nave walling in which
the clerestory windows were placed. Such other buttresses as there had
been were broad and flat, with but little projection from the surface
of the wall. The windows throughout the building up to about the end
of the twelfth century were small in comparison with some of those
which were inserted at various times afterwards.

[Illustration: VIEW THROUGH THE SOUTH TRIFORIUM OF THE NAVE FROM THE
SOUTH-WEST TOWER. _From a photograph by Mr. F. Bund_.]

It has been remarked that the termination of the ear