problem, to follow minutely his directions, and to build the actual
chalice described in the eleventh century. To apply the gems and
pearls Theophilus directs us to "cut pieces like straps," which
you "bend together to make small settings of them, by which the
stones may be enclosed." These little settings, with their stones,
are to be fixed with flour paste in their places and then warmed
over the coals until they adhere. This sounds a little risky, but
we fancy he must have succeeded, and, indeed, it seems to have been
the usual way of setting stones in the early centuries. Filigree
flowers are then to be added, and the whole soldered into place in
a most primitive manner, banking the coals in the shape of a small
furnace, so that the coals may lie thickly around the circumference,
and when the solder "flows about as if undulating," the artist is
to sprinkle it quickly with water, and take it out of the fire.
Niello, with which the chalice of Theophilus is also to be enriched,
stands in relation to the more beautiful art of enamel, as drawing
does to painting, and it is well to consider it here. Both the
Romans and the Anglo-Saxons understood its use. It has been employed
as an art ever since the sixth and seventh centuries. The term
"niello" probably is an abbreviation of the Italian word "nigellus"
(black); the art is that of inlaying an engraved surface with a
black paste, which is thoroughly durable and hard as the metal
itself in most cases, the only difference being in flexibility;
if the metal plate is bent, the niello will crack and flake off.
[Illustration: FINIGUERRA'S PAX, FLORENCE]
Niello is more than simply a drawing on metal. That would come
under the head of engraving. A graver is used to cut out the design
on the surface of the silver, which is simply a polished plane. When
the drawing has been thus incised, a black enamel, made of lead,
lamp black, and other substances, is filled into the interstices,
and rubbed in; when quite dry and hard, this is polished. The result
is a black enamel which is then fused into the silver, so that
the whole is one surface, and the decoration becomes part of the
original plate. The process as described by Theophilus is as follows:
"Compose the niello in this manner; take pure silver and divide
it into equal parts, adding to it a third part of pure copper,
and taking yellow sulphur, break it very small... and when you
have liquefied the silver with the copper, s
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