Account of a CHAMBER LAMP FURNACE. By 
ROBERT PERCEVAL, M.D. and MRL A. 
» 
Sannin Las 
— . 
Dre Jamp furnace, of which a figure is annexed, Read March 
I have found convenient in many chemical experiments. It — 
confifts of a cylindrical body, 4; inches diameter and’ 93 high, 
(a, Fig. 2.) furmounted by a laboratory (or fpace for containing 
veffels) which is a hollow truncated cone, 63 inches wide at top’ 
and 4+ at bottom (4, Fig 2.). Its conical fhape adapts it to veflels: 
t - of different fizes. To the infide of the laboratory are riveted 
. fix tubes 2ths of an inch diameter, (c, c, Fig. 2.) on which the veflel 
refts, fo that {pace fufficient for the paflage of heated air is inter- 
pofed between it and the infide of the laboratory. To three of 
thofe tubes the iron fpikes marked A in figure the fecond, are 
fitted, which may be introduced into them occafionally. The 
converging extremities of thefe form a fupport for veflels, the 
bottoms of which are lefs than 41 inches in diameter. /n 
ene of thefe tubes, whilft the lamp is burning, is placed the {mall 
N2 pipe 
