an inert enclosing wall, pierced with holes for light,
and with a roof quietly resting on it like a lid
gave place to the thought of a structure which should
be continuous throughout, and energetic in every
part." This is equally true of those astonishing pieces
of architectural engineering which have been built
since the middle of last century and of which the
Galerie des Machines by Cottancin and Dutert was a
typical example. In fact,if there wasarevival of Gothic
in the 19th century, its truest manifestations were in
buildings of this type. Compare St. Pancras Station
with St. Pancras Hotel for true and false 19th century
Gothic.
The feature by which we distinguish the various
periods of mediaeval Gothic is the windowlancet,
rayonnant, decorated and so on. The importance of
glass to the mediaeval architect cannot be overem
phasised, but it fades almost to insignificance beside
its importance to the mode,rn engineer-architect.
Iron or steel construction, in fact, immediately con
notes glass. Paxton, the designer of the Crystal Palace,
coined the term "ferro-vitreous" to describe this
type of construction, and in the Crystal Palace he
popularised it to an extent that has only lately been
appreciated. And ferro-vitreous construction, as
demonstrated in the Crystal Palace, the Galerie des
Machines, the Bauhaus by Gropius, Corbusier's Cite
de Refuge and Immeuble Clarte, and, to take home-
lierexamples, in King'sCrossandPaddington Stations,
is, if not a direct descendant, at least a collateral of
the humble greenhouse.
At the beginning of the 19th century two significant
innovations occurred; one was the introduction of
iron frame construction and the other the introduc
tion of the glazed roof in the conservatory. The latter
had the more immediate effect. Indeed there has
hardly been any swifter architectural transition than
took place in the development from the solidly built,
opaque-roofed orangery oftheendofthe 18th century
to the lightly framed glass structure as represented
in Paxton's Great Conservatory at Chatsworth and
Decimus Burton's Palm House at Kew.
The early 19th-century conservatories soon demon
strated the possibilities of glass as a building material.
They also led to an interest in the properties of sun
light apart from illumination, and various crude
imitations of Vita Glass and Calorex (heat-resisting
glass) were attempted by horticulturists and botanists
who realised that there were other qualities in glass
besides its transparency.
Their novel feature was, of course, the glass roof, and
this was soon repeated in arcades, pavilions, domes
and, most important of all, in the great terminal
stations which began to be built in the middle of the
century. In these glass and iron were formidably and
often impressively united. A later development was
in the utilisation of glass in the roofs of industrial
buildings where good natural illumination is not only
