42 FEDERAL nmronrnn.
side of a roof is used, and then Hlling the space or ridge near the top
of the roof in such manner as ingenuity or taste may dictate. By
the invention described in the hrst claim, the space between the roof-
stones is filled by a single massive cap-stone, the edges of which
lapped over the roof-stones, and which rested upon the gables. The
device seems to be a simple one, and easily conceived, if the vault-
owner possesses the pecuniary ability to provide granite of the requi-
site length. But the description of the tomb of the family of Bil-
land, which is contained in volume 13 of the French work entitled
"Revue Generale do l’Architecture et des Travaux Publics," shows that,
in view of the existing knowledge in regard to structures of this kind,
there was no invention in the patented device. The article says:
"Above this ordonnance extends an entablature, on which is supported the
two sloping sides of the roof, which finish the edifice. The entablature is
composed of three stones, hollowed out so as to form a species of vault, which
marks the size; and these stones, jointed together by rebates, are bound, and,
as it were, tied together by the two thick (hard) slabs of stone, which cover
their sloping sides, by means of the hollow made on the lower sides of the
former, (the slabs,) in order to clamp the projections retained on the stones
of the vault. These stones are, in their turn. tied together by the ridge which
surmounts the building."
The plates which are attached to the description show that the
Billand roof consists of two sloping roof-stones, each being a single
piece, fastened by projections and cavities to gable-stones, each being
in one piece, and a single ridge-stone, covering the joint where the
upper edges of the roof-stones meet, and not resting on the gable-
stones. The difference between the Billand roof and the roof of the
patent is that the roof-stones of the former are so wide that only a
ridge-stone is needed to cover the joint, while roof-stones of the latter
are narrower, and a wider ridge-stone or cap-stone is needed, which
must, of course, be interposed between the roof-stones, and must rest
upon the gable. The ridge-stone of the Billand tomb is a small cap-
stone, which bound the roof-stones together, and which covered the
joint made by their edges. The cap-stone of the patent is a larger
and wider ridge-stone than that of Billand, and, by its great weight,
is more eihcient in holding the structure together. In order to pro-
duce the patented device, the customary skill of the worker in stone
neither needed nor received any aid from the inventive faculty.
The bill should be dismissed.