astern arm which is characteristic of cathedrals and monastic churches.
This may be seen very clearly at Iffley, near Oxford, and Avening in
Gloucestershire, where vaulted chancels of the twelfth century were
lengthened in the thirteenth century by an eastern bay. Sometimes, as at
St Mary's, Shrewsbury, where successive generations of builders were
very faithful to the remains of earlier work, the old sedilia of a
twelfth century chancel have been left in place. But, as a rule, the
enlargement of the chancel implied an entire reconstruction, or the
entire transformation of old work by the insertion of new windows or
buttresses. From the end of the twelfth century onwards, the normal
chancel of the parish church has a length which is from a half to
two-thirds of the length of the nave, the nave being slightly broader
than the chancel. This is the case with most of those Norfolk churches,
which may be regarded as the ideal examples of parish church planning.
Room was in this way secured both for the altar and the quire stalls,
for which the ordinary rectangular chancel offered a very restricted
space.

Sec. 67. Sometimes a new chancel encroached upon the nave. This happened at
Skipwith in Yorkshire, where the church underwent some alteration about
the middle of the fourteenth century. The new chancel was made of the
same width as the nave; and apparently the old chancel arch was entirely
removed, and its site, with the part of the nave immediately west of it,
made into an extra bay of the chancel. No new chancel arch was built.
One of the most curious and perplexing instances, in which additional
westward room has been given to the chancel, and there is no structural
division between chancel and nave, is at Tansor in Northants. The
perplexity which arises here is due to the plentiful re-use of old work
by the builders, the presence of which in unexpected places makes the
history of the building a nearly insoluble puzzle. The church reached
its present length about 1140, when probably the Saxon nave was left as
the west part of a church, which was now of the same width the whole way
through, and had no chancel arch. Some forty years later, narrow aisles
of three bays were added to the nave; and, about the same time, a
transeptal chapel may have been thrown out from the south wall,
immediately east of the south aisle. As the church stands on southward
sloping ground, there seems to have been no room for another chapel on
th