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however, that this method of establishing the voussoirs, although the strongest
(or indeed dividing the upper hanse to their geometrical striking point at cen-
tre marked 0), makes them noticeably smaller.
On the right-hand side of the same arch, Moxon shows an alternative method,
with accompanying explanatory text, whereby the courses of the scheam and
hanse divide into equal voussoir sizes, deemed visually more harmonious.
It is interesting to note that, until the Restoration, it was generally the ten-
dency for arches of whatever size to be constructed in half-lapped stretcher
bond. In Moxon's treatise his arch is drawn in English bond. This reflects a
change in fashion towards showing some arch faces in aesthetic quarter-bond,
which appears to be uniquely English; though its use also spread to the British
Colonies. Indeed, the flat arch of Helder's masterpiece of 1675 (at the Victoria
and Albert Museum) is constructed with an English Bond face. The same bond-
ing is also used for the gauged flat arch above the entrance doorway to the
south wing of Morden College, Blackheath (Kent) (1695). Generally, however,
it is Flemish bond that was preferred when quarter-bonding a flat arch face,
that being a voussoir course bonded stretcher and header, followed by a course
bonded header, closer, stretcher.
Moxon has two errors on either side of his drawing of the English bonded
semi-elliptical arch. On the left-hand side the error is simply one of scale, as
the central header between the two closers appears like a stretcher compared
with the other headers in the same course. On the right-hand side, however, the
bond is incorrect, as one of the 'closers' is placed on the stretcher course instead
of being placed between the headers, as correctly depicted on the left-hand side.
This quarter-bond was often a part-aesthetic, created by 'scribing' false
or 'dummy' joints on to the constructional half-bonded brick veneer to cre-
ate the illusion of thick-walled English or Flemish bond. An interesting use of
dummy joints has been noted on a half-bonded gauged semi-elliptical arch to
the main gateway at Chatham Dockyard (Kent) (1718), to create the illusion
of English bond (Fig. 86).
Figure 86
Semi-elliptical gauged
arch to the main
gateway, Chatham
Dockyard (Kent), 1718.
(Courtesy of Nigel
A. Howard)
