Mechanical and Technical Processes. Materials 133
nets. Netting needles are common, especially in the New
Kingdom and Roman times.
Faience was made as early as predynastic times, and by the
Third Dynasty had reached a high degree of excellence (see
Fig. 5, facing p. 127). It consists of a body material of very fine,
clean, angular grains of quartz without any visible admixture of
clay or other ingredient. The quartz has the appearance of
having been artificially powdered. The adhesive most probably
used was natron from the Wady Natrun. In the experiments
conducted by Mr. Lucas a mixture of quartz powder strongly
fired with 10 per cent, of natron produced a mass closely resem-
bling ancient faience. After heating, only about 3 per cent, of
the natron remained in combination, the rest having volatilized.
Since the number of analyses of ancient faience are still com-
paratively few, this may account for the adhesive not having
been recorded. The usual method of making faience objects
was by casting them in pottery moulds, of which thousands
have been discovered of all periods. It is possible, however, that
in certain cases the fused mass of quartz and natron was carved
as if it were stone. Faience was used for vases, statuettes,
amulets and inlay. It can take a high glaze, but the method
of its application is still uncertain; in fact, although most careful
experiments are now being carried out, we are still only able
to give the broad lines of the process of faience manufacture.
The chemical composition of glass and glaze is identical (Fig.
10, facing p. 134), namely the result of a complete fusion of
quartz sand containing calcium carbonate with natron or plant
ashes and colouring matter. The term glaze is used when the
substance is applied to some material such as stone or faience,
while glass is applied to objects made entirely of this substance.
Glazed beads are known from the predynastic period, but the
specimens of glass ascribed to periods earlier than the beginning
of the Eighteenth Dynasty are all of somewhat dubious date.
Blown glass is not known until the Roman period; the Egyptian