382 C H E M 
New GAZOMETER of the PHILOSOPHICAL 
SOCIETY of LONDON. 
This improved apparatus* recently conftru£ted for the 
production or formation of water, by the combuftion of 
hydrogen gas in oxygen gas is • accurately delineated in 
the Cheiniftry Plate IX. fig. r, where AB reprefents a 
light globular veflel of flint glals, about twelve inches in 
diameter, in the manner of an adopter, having the nar¬ 
row necks A and B oppofite to ea"ch other. -The lower 
part of this veffel is drawn out at C, to form the tube 
C D, which is provided with a flop cock at its. lower ex¬ 
tremity D.‘ The fquare mahogany frame F G (lands pa¬ 
rallel with the horizon. Near the end K of a mahogany 
board, the brafs rod MN is (crewed fo as to (land up¬ 
right; it is provided with a (houlder, in order that it 
may be firmly fixed into the plate M O, fattened at each 
angle to the board with fcrews. In the fame manner the 
rod PQJs fattened at the otherend of the board K, which 
fattening cannot be feen in this view of the apparatus. 
Tbefe rods pafs through the fquare frame F G at H and 1 , 
fo that it may be tlidden upwards or downwards on the 
rods. At each hole in this frame, through which the 
rodpaffes, a brafs focket Ha, is (crewed to the lower fide 
of the frame, fo that the rod may pafs freely through it; 
and that it may be fixed at any elevation, the focket is 
provided with a fcrew H, by which the rod may be prefix¬ 
ed againfl: the oppofite fide of the focket, and thus kept 
in the pofition required. The oppofite fide of the frame 
near I, is in the fame manner provided with a focket and 
fcrew. 
The veffel Q^, containing water, has a tube fixed in 
the centre of its bottom, which receives the rod, and 
flides on it, fo that the veffel may be (uftained at any re¬ 
quired height. By means of a (lop cock b the water 
rnay be made to trickle more or le(s quickly from the 
veflel Q, upon a piece of muflin c, by which it is diftri- 
buted over the whole furface of the adopter A B, and 
defcends by CD into the lquare trough D, after having 
ferved to cool the adopter; d is a glals funnel, cemented 
into a brafs cap at nr, from which the tranfverfe tube 
22 e, provided with a (lop cock, may deliver the hydro¬ 
gen'gas of the funnel d into the adopter, through the 
(lender extremity e, made of iron, left it fhould be melted 
by the-flame of the hydrogen gas. 
Under the other neck of the adopter (lands the funnel 
g, furnifhed with -a (top cock at f, intended to receive and 
deliver oxygen gas by the courfe g g A into the adopter, 
in order, to maintain the combultion of the hydrogen 
gas. Through a collar of leather, fixed in the tube be¬ 
tween i and A, an iron-wire paffes, bent in the direc¬ 
tion A e: the end of this wire at e is at the diftance of 
one-eighth of an inch fiom the end of the tube which 
Jfupplies the hydrogen gas, when the wire (lands in this 
pofition to deliver the eleftrical fpark, and inflame the 
hydrogen gas as it iffues. The end of the wire at i, is 
(crewed into a fmall brafs ball, by which it receives 
(parks from the larger ball k of the eleftrical conductor. 
"The funnel containing oxygen gas enters water to the 
depth of three or four inches in the veflel R S, the fize 
of which admits a pint bottle of gas to be introduced 
under the funnel and delivered into it. The veflel T U 
ferves in like manner for the fupply of hydrogen gas to 
the funnel d. 
When it is intended to accelerate the combuftion of 
the gafes, the hydrogen funnel mull be kept conftantly 
full, fo that it may be prefled upwards by a column of 
three or four inches of water: at the fame time the oxy¬ 
gen funnel muft be fupplied fo (lowly, that the water may 
rife in it five or lix inches above the common level. In 
the contrary circumftances the combuftion may be re¬ 
tarded at pleafure ; but care muft be taken that the hy¬ 
drogen gas ilfue in a continued dream, and the flame be 
maintained, a 
I S T R Y. 
As it is neceffary that the adopter (hould be firmly 
fcrewed to the fquare frame, and yet eafily feparable 
from it, the following provilion is made : ab as the neck 
of the adopter through which the gas is to be introduced. 
The lip at b (trengthens the mouth of the adopter, d is 
the external projecting part of the glals ltopper, which 
is accurately ground to fit. This (topper being ground 
to a fmaller diameter between d and g is there cemented 
into a brafs capg/l The (lender wire which is to deli¬ 
ver the ele&ric fpark is continued through the glals Hop¬ 
per d to i. The oxygen funnel g communicates by a 
narrow paffege with the cavity of the adopter round the 
wire i e. The neck of the adopter is imbedded in the 
mahogany frame; the brafs clip b (huts upon this neck, 
and preffes it to the frame by the fcrews i i. To keep 
the (topper d firm in the neck of the adopter, a fenticir- 
cular clip embraces the brafs cap g f, and meets the 
(boulder of the (topper d. From this clip two brafs pins 
enter the piece k, which being drawn to the flame by 
the fcrews ll, forces the clip againfl; the glafs (topper d, 
and thus fattens it firmly in the neck ot the adopter. 
By the like mechanifm the other neck of the adopter is 
made faft to the frame. 
The wire ie, being moveable in a well-greafed collar 
of leather, the brals ball i is turned round, when the 
hydrogen gas has been inflamed ; and the wire A e turn¬ 
ing with this ball, the end e is removed to one fide 
from the flame of the hydrogen gas; the fcrew m ferves to 
keep the wire in the pofition required. 
Previous to the ufe of this inftrument the funnels are 
to be fcrewed off: the oxygen funnel at f; the hydrogen 
funnel at the. neck B, of the adopter. The hydrogen 
(topper being removed, the adopter is to be rinfed with 
diftiiled water, and, being again put in its pofition on 
the frame F G, is to be left to drain, the tube C D being 
left open. After this the adopter with its (toppers and 
included air is to be weighed : the hydrogen (topper be¬ 
ing then removed, the adopter is to be filled with diftiiled 
water of a known temperature, and the (topper to be 
again replaced. By the weight of the water in the 
adopter its capacity in cubic inches is afeertained. 
The fame (topper is now to be taken out and dried, 
and oxygen gas, under a preflure of a two-inch column, 
of water, to be introduced till all the water is excluded 
from the adopter: its orifice, being (till under the wa¬ 
ter, is then covered with the finger, and another perlon 
ftands ready to introduce the (topper, which has to ex¬ 
pel its bulk of gas, lo that no air can enter againfl; this 
current of the gas. The adopter is now fattened to its 
frame, and the funnels are fcrewed on. To prevent the 
hydrogen tube from introducing the atmofpheric air 
which it otherwife would hold, oxygen gas is lucked 
through it from the fmall extremity. 
The funnels, the capacities of which are determined 
by meafurement, and marked at the different heights, 
now contain atmofpheric air confined by water, which 
is to be fucked out by means of a (lender fyphon: when 
the oxygen funnel is thus emptied of its air, in order 
that none may remain in the neck, oxygen gas is to be 
introduced and fucked out repeatedly. Then it is to be 
charged with the fame gas, and the flop cock to he open¬ 
ed to'allow a free communication between the gas in 
the funnel and that in the adopter, which is now left to 
drain for twenty-four hours, at the end of which time 
the water which has gathered in the tube CD, is to be 
puffed off by opening the cock D, which mult juft touch 
the furface of the water in D, that the oxygen gas in 
the adopter and funnel may accommodate itfelf to the 
prefent temperature and preflure of the external air, 
which is to be noted, and then the cock to be (lopped. 
The water on the outfide of this funnel is to be kept two 
or three inches lower than in the infide. The hydrogen 
funnel d is to be freed of its contained atmofpheric air 
by the lame means employed for freeing the other funnel. 
