£52 
GLASS. 
Binning of glass vessels. The furnace for j the neck cl with a wet iron, cracks the glass, 
this (fig. 5. Plate Manufacture of Glass) has j so that a slight blow upon the rod with the 
•several mouths, according to the number of : hand will separate it at d, from the blowing- 
workmen. Each mouth consists of three holes, j pipe M. The glass has by this time become 
ABD ; D is a hole through which the work- j too cold to work without heating again, 
man takes his metal from the melting-pot ; j which is done before the fire A, fig. 5 ; the 
A is the hole at which he afterwards heats his 
metal; and B is a small hole at which he 
heats the ends of his blowing-pipe and iron 
rods an, which are supported by an iron bar 
across the mouth of the furnace. The fur- 
nace is built of fire-bricks, and has three 
adorned chambers, one above another, within 
it ; the fire is made upon a large grate in the 
middle of the lower one, to which the air is 
admitted by an arch underground ; the flame 
goes through an opening in the dome of this 
chamber, and strikes against the top of the 
next chamber, and is thereby reverberated 
upon the pots, which stand upon the floor, 
just within the hole D ; the smoke goes 
through the floor and roof of the next chain- 
workman then returns to the stool, fig. (5, 
and again rolls the rod round with his left 
hand as before, and with the point of one of 
the blades n of the shears opens the end d, 
fig. 8, of the glass; after which he inserts 
both points, and finally works it into the form 
of fig, id. It is now separated from the rod 
N, and "is carried on a shovel like a baker’s 
peel by the bey to the annealing furnace, or 
oven in the upper part of the furnace, where 
it remains ru a low red-heat for many hours, 
bv which its former extreme brittleness is re- 
moved. 
W inflow-glass is made in a similar manner, 
except that the liquid mass at the end of the 
tnbe is formed into a cylindrical shape, which 
ber, which is used as an annealing oven. This j being cut longitudinally by scissors or shears 
furnace is inclosed w ithin a large building, 
like an inverted funnel, with a chimney at 
tire top. 
The principal implements used by the 
glass-blower, are, a blowing-pipe, fig. 1, 
whieh is an iron pipe about two feet Tong, 
with rope-yarn wrapped round it at A, where 
the workman takes, hold of it; two or three 
fron rods, rig. 2, of the same length; a pair 
of blunt shears, fig. 3 ; and several different 
sized ladles, shovels, pokers, See. He has 
also two stools, figs. 6 and 7, to be hereafter 
described. 
For explaining the operation, we shall de- 
scribe the method of making a goblet. 'The 
workman dips the end D of his blowing-pipe, 
fig. 1, which is hot, through the hole D, %. 
A, into the melting-pot, which contains the 
glass in a state of fusion; and by turning it 
about, a small quantity of the glass, which is 
called metal, sticks to the iron: this he re- 
peats three or four times (between each dip 
rolling it on an iron plate, fixed on the stool, 
fig. 7, to bring it into form) till he lias got 
metal enough : he then blows at the end B 
of the pipe, which expands the metal into a 
is gradually bent back until it becomes a flat 
plate. 
Large plate-glass for looking-glasses, &c. 
is made by suffering the mass in a state of 
complete fusion to flow upon a table, with 
iron ledges to confine the melted matter, and 
as it cools a metallic roller is passed over it, 
to reduce it to an uniform thickness. 
Good glass ware is often ornamented by 
the glass-cutter before it is offered for sale 
(see fig. 12.); this is generally performed bv 
a machine, fig. 14, wherein A A is a large wheel 
to be turned by a man at the winch B. The 
band of this wheel passes round a pulley a. 
on the axle of a wheel or cutter G, and there- 
by turns it with a great velocity : beneath 
the cutter a cistern D is placed, and above it 
a small cask E to contain water, the cock b 
of which is so placed and adjusted as to drop 
very slowly on the circumference of the cut- 
ter. The glass-grinder sits down on the stool 
F, and after dressing the edge of the cutter 
with emery paste, he applies successively the 
parts of the glass which are to be cut, as 
shewn in fig. 11, and dexterously moves the 
glass, as the parts intended to be cut are suf- 
hol low globular form ; and then by swinging iiciently ground away: after this another 
it round his head, it lengthens out in the similar cutter is applied instead of C, or the 
same is dressed with liner emery paste, or 
mixture of tripoli and other polishing pow- 
ders, in order to polish the parts which have 
shape of a bladder. The workman then sits 
down on the stool, fig. 6, between the two 
bars H and I, across which he lays the blow- 
ing-iron, and rolls it along under iiis left hand, 
following it at the same time with the shears, 
fig. 3, in his right hand, the blades nn of 
been cut; such parts as are intended to have 
a white appearance are left rough. The cut- 
ters c are formed of hard wood or soft me- 
which embrace it, and by gently putting ! tal, and the workman is provided with seve- 
tliem in the proper place, he brings the glass ! ral, of different sizes and thicknesses, particu- 
into tne form shewn in fig. 10; meanwhile, Marly at the edge, according to the device 
the boy who attends him brings a lump of 
metal from the furnace on the end of one of 
the iron rods fig. 2, which he sticks on the 
bottom, or part a, fig- 10, and by twisting 
the rod round, lie separates the metal from 
the rod, and leaves it on the glass vessel ; 
the workman then rolls the rod and vessel as 
before, and with his shears, as shewn in fig. 9, 
brings the lump of glass into the form of a 
stem and foot, as there described. The boy 
then holds the tool, fig. 4, against the bottom 
of the foot b, while it is turning, to flatten it. 
The boy next takes another iron rod, fig. 2, 
and o-ets a very small piece of metal on its 
end Ahis he applies to the centre of the bot- 
tom of the foot, so as to connect it to the 
rod; when the workman, by touching it at 
which is to be cut on the glass. It is by the 
fine edge of these cutters that letters, flowers, 
&c. are cut on glasses by dexterous workmen. 
Glass, painting on. A few years since, 
Mr. Earrant obtained a patent for painting, 
spangling, gilding, and silvering glass, which 
was performed on the back of the crystal or 
glass, so as when finished to appear on the 
front; the colours prepared in oil or varnish 
as in other works. 'I he parts of ornament 
which are gold must be first shadowed on the 
glass, and when dry the gold leaf must be 
laid on. Silver ornament is to be done in 
the same manner. For the spangling, leave 
the parts to be spangled to the last; then 
shadow them, and when dry varnish- the- parts 
with copal varnish, and strew the spangles 
b 
on while it is wet ; when they are dry, var- 
nish them two or three times. 
The antient manner of painting in glass was 
very simple, and consequently very easy : it 
consisted in the mere arrangement of pieces 
of glass of different colours in some sort of 
symmetry, and constituted what is now call- 
ed mosaic work. 
In process of time they came to attempt 
more regular designs, and also to represent 
figures heightened with all their shades: yet 
they proceeded no farther than the contours 
of "the figures in black with water-colours, 
and hatching the draperies after the same 
manner on glasses of the colour of the object 
they designed to paint. For the carnation, 
they used glass of a bright-red colour, and 
upon this they drew the principal lineaments 
of the face, &rc. with black. 
But in time, the taste for this sort of paint- 
ing improving considerably, and the art 
being found applicable to the adorning of 
churches, &c. they found out means of incor- 
porating the colours in the glass itself, by 
heating them in the fire to a proper degree,, 
having first laid on the colours. The co- 
lours used in painting or staining of glass are 
very different from those used in painting 
either in water or oil colours. 
For black, take scales of iron one ounce, 
scales of copper one ounce, jet half an ounce \ 
reduce them to powder, and mix them. For 
blue, take powder of blue one pound, sal 
nitre half a pound ; mix them, and grind 
them well together. For carnation, take red 
chalk eight ounces, iron scales and litharge of 
silver of each two ounces, gum-arabic half an 
ounce; dissolve in water ; grind all together 
for half an hour as stiff as you can; then put 
it in a glass and stir it well, and let it stand 
to settle 14 days. For green, take red-lead 
one pound, scales of copper one pound-, and 
flint five pounds ; divide them into three 
parts, and add to them as much nitre; put 
them into a crucible, and melt them with a 
strong fire ; and when it is cold, powder it,, 
and grind it to a porphyry. For gold-colour, 
take silver an ounce, antimony half an ounce • 
melt them in a crucible ; then pound the 
mass to powder, and grind it on a copper 
plate; add to it yellow ochre, or brick-dust 
calcined again, 15 ounces, and grind them, 
well together with water. For purple, take 
minium one pound, brown stone one pound 
white flint five pounds ;. divide them into 
three parts, and add to them as much nitre 
as one of these parts; calcine, melt, and 
grind it as you did the green. For red, take 
jet four ounces, litharge of silver two ounces, 
red chalk one ounce ; powder them fine, and 
mix them. For white, take jet two parts, 
white flint, ground on a glass very fine, one 
part, mix them. For yellow, take Spanish 
brown ten parts, leaf silver one- part, anti- 
mony half a part ; put all into a crucible,, 
and calcine them well. 
In the windows of antient churches, Stc. 
there are to be seen the most beautiful and 
vivid colours imaginable, which far exceed 
any of those used by the moderns, not so 
much because the secret of making those 
colours is entirely lost, as that the moderns 
will not go to the charge of them, nor be at 
the necessary pains. Those beautiful works 
which were made in the glass-houses were of 
two kinds. 
In some, the colour was diffused through 
