» of the building, and at both ends, when the vessel 
rises till the recess 4c receives the end of the Pipe fi 
that the lower end of p will be above the water. e 
will therefore rise through p, and pass forward 
zh f into the open air, and hus prevent its escape 
into the room. ' 
In carrying on the process, the water in the vessel 
AB will frequently require to be changed, as well from 
being contaminated with the remaining impurities of 
the gas, as from becoming warm by the pipes from 
the retort ing through it. Where water is very 
plentiful, it would be advisable to have a constant cur- 
rent of warm water from the of the vessel, and a 
cold current in at the bottom, The lime-water in the 
lime-vesse) L, Fig. 7, will require changing much of- 
tener than in the vessel AB. The sulphureous acid, 
carbonic acid, and sulphuretted hydrogen, which come 
with the carburetted hydrogen, are all taken up b 
the lime, forming sulphate, carbonate, and hydrosul- 
sare of lime. From this it will be obvious, that the 
ime will ultimately be all consumed ; but it should be 
removed long before it arrives at complete saturation. 
The mixture of lime and water in the vessel m should be 
about the thickness of cream, and hence has been call- 
ed the cream of lime. When the liquid in the vessel 
L requires to be changed, the plug & is taken out, 
while the plug s is kept secure. When the vessel L is 
emptied, the plug k is replaced, and the plug s taken 
out, The fresh lime and water in m is now transferred 
to L; the proper quantity being as much as will ran 
in till m remains full, It must be here observed, that 
the vessel m is rather a measure with which to fill the 
vessel L to a proper height, -than a reservoir. It is 
hence Free to be supplied from a large-eistern, in 
which the cream of lime is prepared in considerable 
‘quantity. — 
eon- When the gas has been carried through the pipe 
of zgy, and its different ramifications, to the places where 
it is to be burnt, the passage terminates in a small ap- 
paratus, called a burner, perforated with one or more 
small holes, about one-thirtieth of an inch in diameter: 
The most simple of these terminates in a spherical sur- 
face, as seen in Fig. 9. There is one hole in the cen- 
tre, and several others around it. The surrounding 
_ holes, if it were not for the upward current of air, 
_ would give flames, radiating in straight lines from the 
centre of the spherical burner ; but the upward motion 
of the heated air causes the flame to curve upwards, 
like the spur of a game cock, and hence they have been 
Leohentcally called cockspur burners. Fig. 10. is a 
bracket, at the end of which is a burner, terminatin 
in the face of a cylinder, near the outer edge of whieh 
is a circular series of holes, from which the flame rises 
perpendicularly. These are surrounded by a glass like 
the Argand lamp. In its general appearance it is so 
like this lamp, as to have acquired the name of the Ar- 
gand burner, Figs. 11. and 12. are a plan and section 
of this burner upon a larger scale. The holes in the 
inner circle, Fig. 11. are supplied with gas from the 
cavity C, Fig. 12: The same holes appear in section at 
ab, Fig. 12. holes in the outer circle, Fig. 11. com- 
municate with the cavity e f, Fig, 12. which also com- 
municates with the atmosphere by the openings ik; gh, 
is an ornamented rim for the reception of the glass. The 
air from the glass becoming heated by, the flame, rises, 
and a current takes place from ik, through the cavity ef, 
and between the burner and the¥glass, This current 
in the Argand lamp is both within and without the 
circular flame, and serves to supply the lamp with oxy- 
| 
‘ 
GAS LIGHTS. 117 
for burning the smoke, as well’ as to keep the Gas Light# 
data steady. In the gas lights there is no smoke to ““\—" 
burn: the current of air, therefore, is not so essential, Prare 
It has the good effect, however, of keeping the flame CCLXIV. 
steady, which otherwise would be agitated by the "is: 10. 
slightest motion of the surrounding air. Fig, 10. shews 
the manner of bringing the gas to stypply a bracket~ 
lamp fixed to the wall: The stop-cock a is connected 
with the pipe behind the board ¢d, which also commu- 
nicates with the pipe leading to the burner. Tig. 9. 
is provided with a similar plate to screw to the wall. 
These brackets are capable of moving in a horizontal 
direction. The end of ‘the tube 5 is ground into the 
little globe s, so that it will turn round without allow- 
ing the air to escape. Fig. 9. is similarly constructed. 
A great variety of these ornamental brackets, chande- 
liers, candelabras, &c. will be found in Mr Accum’s 
work upon gas-lights. 
\ The apparatus above described, is upon a small 
scale compared with what would be required for 
lighting a large manufactory, or. upon the scale prac- 
tised for lighting the streets and shops in the me-+ 
tropolis. The gazometer, lime-vessel, and tar vessel, 
are all made of cast and wrought iron, precisely in 
the same way that would be recommended upon the 
largest scale. It would be found impracticable to in- 
crease the fire and the retort to the same extent to which 
the other apparatus may be increased. It would be im- 
proper to make a fire to heat a greater length than from 
six to eight feet. And if the cavity of the retort were 
more than 12 inches wide, .the coal would not be com- 
pletely decomposed in the centre. it is found, there- 
fore, more advantageous»when a greater supply of gas 
is wanted, than would be afforded-by. a vessel of* the 
above dimensions, to use additional retorts and fires, 
all communicating with the same gazometer, lime-ves- 
sel, &c. ‘In Fig. 7. there is but ‘one furnace, but it 
may easily be supposed that a series of furnaces may 
join this on the left hand. Each retort having a tube 
n, they may all be corinected with one common pipe c, 
which is the condensér: to show this, the pipe cin 
this figure is broken off on the left hand. 
When the vessel D ismade very large, it requires to 
be first formed in a skeleton of wrought.or cast iron, 
and afterwards covered with iron plate. 
It is strongly advised, where it is practicable, that 
the retorts should be kept in constant action night and 
day for the season, or at least never allowed to go be- 
low a red heat. The-first portion of oxide which forms: 
upon the surface, when allowed to cool, cracks and falls 
off, leaving a new’ surface to be acted upon the next 
time it is heated, By thus being every day heated and 
cooled, a retort will be destroyed in a few months. When 
they are kept continually red hot, they frequently last 
three winters. The writer of this article is indebted 
to Mr Lee of Manchester for this fact. 
In discharging the retort at a red heat, the coak 
may drop through an-opening into a cellar.below, the 
hole being afterwards closed ; without this contrivance, 
the operation would be much annoyed. In applying 
the gas lights to the streets and shops, pipes of cast 
iron are employed running along each side of the street, 
of different sizes, from two to four inches in diameter, 
according to the supply. The main streets have larger 
pipes, called mains, from which smaller pipes proceed 
to light the cross streets, alleys, and courts. The 
pipes are perforated opposite to the shop to be light- 
ed, and an iron pipe ground air tight into the hole. 
With this, other iron pipes are connected to convey, 
