plastered outside as well as
in; and what is more remarkable, no other sign of the vault appeared
outside the building than the buttresses required to sustain it.

The external gable conforms to the shape of the roof which covered the
vault, but the vault, perhaps the most remarkable and characteristic
feature of the whole building, does not betray its presence by any
external line or mark corresponding to its position and shape in the
interior of the building. Notwithstanding these and some other
exceptions, frank disclosure must be reckoned one of the main
principles of Gothic architecture.

[Illustration: FIG. 60.--DOORWAY FROM CHURCH AT BATALHA.
(BEGUN 1385.)]

Elaboration and simplicity were both so well known to the Gothic
architect that it is difficult to say that either of these qualities
belongs exclusively to his work. But he was rarely simple when he had
the opportunity of being elaborate, and simplicity was perhaps rather
forced upon him by the circumstances under which he worked, by rude
materials, scanty funds, and lack of skilled workmen, than freely
chosen. Many of the great works of the Gothic period are as elaborate
as they could be made (Fig. 60), and yet, when simplicity had to be
the order of the day, no architecture has lent it such a grace as
Gothic.

The last pair of qualities is similarity and contrast. What has been
said about repetition has anticipated the remarks called for by these
qualities, so far as to point out that even where the arrangement of
the building dictated the repetition of similar features, a general
resemblance, and not an exact similarity, was considered sufficient.
In the composition of masses of building, contrast and not similarity
was the ruling principle. Even in the interiors of great churches
which, as a rule, are far more regular than the exteriors, the
contrast between the comparative plainness of the nave and the
richness of the choir was an essential element of design.

External design in Gothic buildings depends almost entirely upon
contrast for its power of charming the eye, and it is this
circumstance which has left the successive generations of men who
toiled at our great Gothic cathedrals so free to follow the bent of
their own taste in their additions, rather than that of their
forerunners.

But setting aside the irregularities due to the caprice of various
builders, and the constant changes which took place in detail through
the Gothic pe