A) 
. $16 . GLASS. 
Stainng of ence base, add the above colouring powder, but dimi- dark as to the effect of his picture, because the colours St 
Glass." nished a fourth part: or, 2. To 20 ounces of the base 
made with flints, add the same colouring powder, but 
with a fourth less of the manganese. 
For the Brazil Topaz.—To 2 ounces of the second 
or third base, add, for colour, 1 ounce 24 grains of the 
glass of antimony, and 8 grains of the precipitate of 
Cassius. 
For the Saxon Topaz.—To 24 ounees of the first or 
third base, add six drachms ofthe glass of antimony. 
For the Emerald.—1. To 15 ounces of either of the 
bases, add, for colour, one drachm of mountain blue 
and six grains of glass of antimony ; or, 2. To an ounce 
of the second base, add, for colour, 20 grains of glass of 
' antimony, and three grains of calx of cobalt. 
For the Common Opal.—To an ounce of the third base, 
add, for colour, 10 grains of horn-silver, two grains of 
ealcined- magnet, and 26 grains of an absorbent earth. 
Sect. VIII. On. the Art of Staining Glass. 
Glass staining is the method of ornamenting glass for 
the windows of churches, or other edifices, by pictures 
or designs painted in colours, which are made to oa 
netrate into the substancé of the glass, by means of fire. 
Stained glass is frequently called painted ‘glass, but the 
distinction should always be preserved between the paint 
ing with transparent colours upon a surface of glass, an 
the staining or tinging of the glass itself, with the colours 
which produce the picture. As pictures in coloured glass 
are always placed between the spectator and the light, 
they have an effect altogether different from any other 
species of painting ; and, from the transparent brilliance 
of the colouring, the spectator is often struck with admi- 
ration, independent»of any excellence in the subject of 
the picture. 
Transparent colours painted on glass, either in water 
or varnish, can never attain the brilliancy of the colour- 
ed glass, but from the great difficulty of staining ¢er- 
tain colours, it is very common to find, in modern win- 
dows, part of the colours painted on the surface, whilst 
the large tints are stained. 
~ It-was not until the 15th century that the stained 
glass was made to produce the effect of strong lights and 
shades ; but respecting the methods employed by the 
painters of those superb specimens which we find in 
cathedrals, we are wholly uninformed ; and our infor- 
mation is now chiefly drawn from a Memoir of M. Leviel, 
published in the Description des Arts et Metiers, vol. 
xiii. This gentleman was himself a painter on glass, and 
the only one of eminence who has written upon the art. 
The glass upon which it is intended to paint should 
be very hard, without spots, or any colour. Crown 
window glass is the best ; for cast or plate glass -has bo- 
rax in its composition, which would make the colours 
to run or spread. When the design is too large to be 
contained on a single piece of glass, several must be fit- 
ted to ee a oo bed of some resinous cement 
prepared, upon which t can be readil tt er, 
and held on one flat tentie whilst sore part cana 
spaces for the lead frames, and yet be readily separated, 
to subject the pieces separately to the fire. 
~ In arranging the pieces of glass which are to be paint- 
» care must be taken to dispose the joints so that 
' may do the least injury to the design by the opacity of 
the lead frames, by-which the pieces must be joined to~ 
gether, in order to form a large window. 
The design which is intended to be painted upon the 
glass, must be accurately drawn upon a sheet ‘of paper 
in outline ; or, if necessary, in its proper colours. In 
this. species of painting, the artist works quite in the 
they: slit. By working this upon 
are laid on the glass, they‘are either colourless, or pe r= 
‘he upper side of the glass is the 
over with a fine clear gum-wa~ 
ectly dry, forms a surface proper 
to receive the colours, without a of their rannin 
or spreading beyond their intended limits, as wou! 
do if laid upon the smooth surface of the giass, ‘The first 
ration, is to draw upon the glass with a fine pencil, 
I the lines. which are n to produce the shades, 
and to mark the outlines. This is usually done in a 
black colour, orat least'in some deep colours, such as 
brown, blue, or n, and sometimes red. In laying 
on these, the artist is guided’ by the same principles as 
the engraver, when he produces the effect of light and 
shade, by dots, lines, or hatches ; and he employs that 
colour to produce the shades, which will best accord 
with.the colour which is intended afterwards to be laid 
on; but; in general; black is used in the outline for all 
the deeper shades. When this is finished, the whole 
icture will appear represented in lines or hatches simi- 
to an engraving, finished’ up to the highest’ effect 
pessible ; and afterwaiils, when it is perfectly dry, 
9 are laid on by — meee oe ee 
colour is spread upon t the design which ‘re 
quires it ; sn diudeclictheer inane faces of the fis 
gures the green for trees, blue for the sky, &e.; butin 
ing this, the artist labours under the disadvantage of 
being unable to see the effect of his work, until it has 
been subjected to the fire. He therefore avails himself 
of a numberof trials made upon sma poe a glass, 
which he keeps as specimens of the of the diffe- 
the preperation cone iain easpaoye a loring ne 
e Ww em ‘or co - 
must, amt search among these specimens for the 
tint, and apply the proper preparation. i 
In reels the colours, it must be observed, that 
some preparations which produce beautiful colours, are 
liable to run or mix with those which are adjacent to 
them, so as to confound the outlines of each ive 
colour, by producing a mixture of the two. This is a 
serious difficulty ; the artist must refer himself to his 
trials ; and when he finds it nece to lay two ad~ 
joining colours which will run er, he must lay 
one of them on the back of the glass. The few princi~ 
pal colours, of which we shall presently give the prepara- 
tion, are all fast colours such as will not run, except the 
yellow, which must therefore be laid upon the opposite 
side. It should be observed, that those colours which 
will mix or run, are equally useful with the others when 
applied to produce compound tints ; but the artist should 
not attempt to use them without being well acquainted 
with their properties, otherwise he may by a very smalb 
tint of improper colour destroy all his work. 
After colouring, the artist proceeds to uce the 
very light parts of his subject, by taking off the ‘colour 
from them by a goose quill, cut like a pen without @ 
the glass, he removes the . 
colour from the parts where the lights should be the 
strongest ; such as the-hair, eyes, the reflection of bright 
surfaces, and light parts of draperies. The blank pen 
may be either employed te make the by lines, or 
hatches and dots, as will be most. sui ‘to the sube 
ject, and the part where they are required, in the same 
manner as the black was used to ce the shades.. 
