MODERN SURVIVAL FORMS
Superstructures of this type, almost extinct in the Old
World, are a common feature of the timbered barns in the
great farm belt of the United States (fig. 363). This device
was brought over by early settlers, along with the very type
of building for which it had been invented in the Early
Iron Age. Hundreds of thousands, if not millions, of aisled
American hay and dairy barns of timber are ventilated even
today by openings in the roof ridge, which are shielded by
elevated sections of the main roof and which still retain the
shape of what in the Middle Ages was probably the most
common means of controlling light and smoke.
The design of such a device from a barn in the vicinity
of Benicia, California (fig. 364), is probably as good a guide
for the reconstruction of the louvers of the guest and service
buildings on the Plan of St. Gall as any equivalent found in
Europe, where this particular device disappeared rapidly in
residential architecture once the open fire was replaced by
hooded chimneys, a development that must have been
nearly complete by the beginning of the fifteenth century.
Despite a thorough search among Flemish, Dutch, and
German landscape drawings, etchings, and paintings—
media which have richly and vividly preserved the architectural
panorama of the medieval countryside—I have
been able to trace only a single case of survival in post-medieval
architecture, and a belated one at that. In an ink
drawing of 1770 by Jean le Prince, entitled Les Lavandières
(fig. 365) there is shown in the center of the bridge that
crosses a stream an old rectangular house with an opening
in the ridge which is shielded by a raised portion of the
main roof above the spot where in the period of construction
of this house there must have burned an open fire.
Together with the saddle-shaped superstructures over the
ridge of the halls of New College and Magdalen College at
Oxford, this drawing of Jean le Prince may retain the most
truthful visual record of the device which in the guest and
service buildings of the Plan is referred to as testu.
