In Hawksmoor's St. George-in-the-East ( 18) the exaggerated
keystones over the aisle windows are wrong in
relation to the part: when seen close-up they are too big in
relation to'the opening they span. When seen farther back,
however, in the context of the whole composition, they are
expressively right in size and scale.
rectangular openings in the attic story of the rear
fagade of St. Peter's (19) are wider than' they are high, so
that they must be spanned the long way. This is perverse in
relation to the spanning limitations of masonry, which
dictate in Classical architecture that big openings, such as
these, be vertically proportioned. But because one usually
expects vertical proportions, the longitudinal spanning expresses
validly and vividly their relative smallness