GAZ 
the fecrets of courts, and the manners and cuftoms of all 
uel de Marville recommends a fet of gazettes, well 
oa as the fitteft books for the inftruction of young 
perfons coming into the world. 
The firft gazette pubhithed i in thefe at, is faid to have 
been that of Paris, begun in the year , by Theophraft. 
aaa a phyiician of Mac. in his aie of intelli- 
a 
The firft gazette in ee was eg ale at Oxford, the 
court being there, in a fio half fheet, Noy. 7, 1665. On 
the removal of the t to L ondon, the title was changed 
tothe « ‘London anaes The Oxford gazette was pub- 
lifhed on Tuefdays, and the London on Saturdays ; 
have continued to be the days of publication ever fince 
7 Extnaonprvany. 
GAZNA, in Geography. e GHI 
GA: »‘a town = Te eae in Cag 3 106 
miles FE. of Canda har 
GAZOLDO, a town of Italy, in on ees a of the 
Mincio; 13 miles W.N.W. of Mantu 
GAZOM ETER, _GASOMET ER) ated caehe 
or are 
for 
by fuc- 
ceeding | chemifts according: to the obje&ts they had ee 
avoifier’s gazometer confifted of a _ cylindrical a 
aes, , and inferted into another arger 
The eae veffel is 
s in diameter, an Around the 
bottom of this, onits outfide, is fixed a border a into 
Pee) intended to receive leaden weights, 1 x4 
&c. inorder to increafe the weight of the vetlel nee con. 
fiderable ee is requifite. The top of this veffel is fur- 
nifhed with a tube and ftop p-cock, forming a communication 
between the external oad internal air, alfo with a sl gn 
a 
e ; ; 
within. The veffel is eee by achain 
balance beam ; and to the other end a feale 
and weight are fufpended as a counterpoiie. The external 
veffel is partly filled with water, and has tubes along the 
bottom and rifling up to communicate with the air in the inte- 
rior veflel, the purpote of admitting or difcharging it 
le of inches are attached 
effel, t w the height of the water in the int 
and outer veffel, and the differcnce of the heights, in order 
to correct he preffure. Th artial defcription will 
give an idea of the outline of the flructure, which is much 
too complicated to be exhibited as a model for the prefent 
time. 
In the rath vol. of the Annales de Chimie, 1792, is given 
diate object o 
y the flow combuition of hy drogen i in a large glafs recel ver. 
a frean of hy ydrogen gas, and the other oxygen. The hy 
ogen was foe at the commencement of the e experiment 
ri The apparatus difplays ingenuity ; but it 
ae Ges and expenfive. In the 1 ie vol, of the ae 
GAZ 
a fame purpofe; but it is ae too complex and too partial 
vasa for gerferal u 
r. Watt of Bicmingham publifhed a oi ga 
containing a eee of an apparatus for elaftic fluids. 
this he defcribes two veffels, the one under the name of ri + 
draulic bellows, which is, in fac, 
) 
outer veffel, 
other, ad cbou ils inchafunder. T 
ae le at bottom by a circular ion hike fold 
both; and the inner cylinder is fhu: at top by a cover alfo fol- 
dered on. This inner cylinder is ee two inches fhorter than 
the outer cylinder, and the latter is f{urmounted by a cup, 
TW, about 14 inch dec fu pi one inch-all around more 2 
diameter than the cylinc which it is attached. 
pipe, PQ, spa diametialy aro the veflel H; the end, 0, 
18 open e fo be ftopt — 2 
From ne ae PQ, os eae a pipe V, which paffes : 
bse through the cover of the inner Re hi to which it 
s foldered, and is open at its upper end. The fecond veifel, 
J, of the bellows, is a hollow cylinder ef one foot diameter, 
and eighteen inches long, fhut at top, and o 
it is made fo as to move oon and down eafily : the circular 
interitice between the 
fe cover of moved a 
and down, it will a& the part of a bellows, drawing in and 
blowing out air, by the pipes V and P Q. he bellows 
are made of tinned iron plates japanned, or of tinned copper-~ 
plates not japanne 
The air-holder is ; thus defcribed: Let a cylindrical veffel 
. 2.) be made of ftrong tin plate ; this veffel is to be clofe a 
both ends, which are made concave outwards ; clofe to both 
the botto cover, fhort s, U and V, proceed — the 
ipes 
fide of the veffel ; their dort: fhould be the fame the 
pipe, PQ, of the. bellows. Another pipe, T’, paffes chrcaet 
the audi of the cover or upper end of the veffel, to which 
it is well foldered 5 ; and reaches within half an inch of the 
in. o guard this veffel from ruft it fhould be japanned 
both infide and out ; ; and for the aa convenience of ja- 
ae it within, me afunder at the 
middle of it heat can ohn aah may be cemented 
eee by a mixture of: wax and rofin ye hot. When 
this vetlel 3s con su dake the upper pipe, s to have a fhort 
sted into it, a (aula als ft the pipe, Q, 
The low £ pipe V, is then tg be corked, 
ee the eetel filled with a by the central pipe T. This 
veffel 1s to be placed in an empty tub, the pipe, W, inferted 
into the pipe, Q, of the bellows, and cemented toit. When 
the — are filled with ar nie air, pu cork of the lower 
i ,is to be taken out, and the counterpoife of the 
eens is to be lifted up; the water in idles aan will 
then run out into the tub, and the air defcend fon e bel- 
lows into the former vet, ieee when full, muft ae its 
a clofe corked, To transfer the air from this veffel into 
a 
fe) ack water into 
antity of air will i t; then re-cork your veflel until 
you v . more air fro 
In the sth vol. of os Philofopicl Magazine 1799, Mr. 
Pegs deicribes a new me omet principle 
The 
of it is nearly the fame as ce h draulic ties of Mr, 
Watt. A (fg. 3-) isa reprefentation of the bell of the ga- 
4Z zometery, 
