Letters of Mr. Brongniart, with remarks. 21% 
undergo, in arriving at the condition of Porcelain. ‘The cat- 
alogue which is in the box will give you an idea of the order 
of these processe 
Mr. rongniart, as is well known, is director of the great 
National manufactory of Porcelain, at Sevres, near Paris, and 
therefore, authentic specimens, of this kind received from = 
must be regarded as particularly valuable. A mere translat 
of the catalogue, (which is however, fulland detailed) ident 
an exhibition of the specimens, would probably not be very 
useful. We will content ourselves with saying, that the 
Specimens are very instructive, and conduct the observer, 
gradually, from the crude natural ¢ clay, sand, white feldspars, 
decomposed graphic granite, &c. through the regular series 
and delicate translucence, which are among the qualities that 
characterize one of the most perfect and beautiful produc- 
tions of human skill. The tablets that illustrate the paint- 
ing of the porcelain, are particularly elegant, and embrace 
most of the colours that are applied for the purposes of dec- 
oration. 
Gold and platina are applied in the metallic state, and bur- 
a ee and colour of those 
But, in most —- eel cesieepiind 
the icil, are incorporate t, an 
by of sep eien of the porcelain, so that the colours 
cannot be discharged, and are scarcely liable to fade even 
by the action of light. . Thus, cobalt gives an intense blue- 
chrome—a grass-green, and gold-rich purples and violets. 
‘The principle of their ‘application i is the same with that of 
glass and enamel staini ng, and | the superb painted glass win- 
artoctign of the art, an du f th 1 from 
ts entury to century, in "ie splendor.f ‘These iopaie 
finely Sastre by Mr. Brongniart’s specimens, which will 
be freely submitted to the view of those whom either curi- 
osity or interest may allure to this subject. Before return- 
ee reat 
almost unnecessary to colours of 
: iis our common dyes are inapplicable in 
ne ea cor they would of course be 
Vou. IIL.....No. 2. 28 
