Page 491 - Oriental Series Japan and China, Brinkly

MANUFACTURING PROCESSES

colour au grandfeu, sometimes pale, sometimes deep.
According to the quantities added and the cobalti-
ferous richness of the mineral employed, blues of a
character more or less violet are obtained.

" When one examines attentively the manner in

which black glazes were produced on Chinese porce-
lain, one sees that all are not simularly manufactured.
In some cases the black results from the thickness of

the coloured glaze ; in others the superposition of
various colours of different shades produces a tint
of such intensity that it appears black. Sometimes
the black is obtained by superposing brun de laque on
a blue ground : sometimes, again, it is produced by
the inverse process of superposing blue on brun de

laque.

" I conclude here my examination of the principal

fonds de grand feu which characterise Chinese porce-

lains. Evidently the manufacture comprises pro-

cesses which give products very interesting, original,
and beautiful. But these processes are often only
modifications of those in more general use. At the
same time, it is to be observed, inasmuch as the fact

establishes another point of divergence between
European and Oriental manufacturing methods, that

among the colours peculiar to China, some have

evidently been applied to biscuit, that is to say, to
porcelain already stoved. Looking closely at these
colours, they are seen to be cracked, and the crackle,

which is very fine, forms a net-work with very small

meshes. The analysis of these colours, or the simple

test of touching them with fluor hydric acid, shows

that there is a considerable proportion of oxide of
lead in their composition. This naturally places

them in the catalogue of colours used for decorative

VOL. IX. 26