FURNACE. 141 
fuel may be cafily condudled into adjoining chambers, and 
the foot tolledled for forming iamp-biack ; this is ealily 
facilitated by fluUting ttie correfpondent dan;per at tlie 
furnace top, till nearly all the fmoke has entered the 
chamber. F, the furnace bottom, an arch of fire-bricks 
upon edge, in place of a caft iron plate, defcrlbed in fig. 
9. G, one of the apertures by which the fmoke and va¬ 
pour aril'es from the cavity of the furnace ; the damper is 
kept Unit upon the top of the pipe or chimney H, and the 
fmoke is conduffed along the horizontal pipe I, and en¬ 
ters the cylinder Kj the external cylinder I, L, being 
conflantly kept full of cold water, condenfes the fmoke 
in K, which, falling down the internal fides of the tapered 
cylinder, ilfues out below, and is condutted by meatisof 
a vhone, or pipe, to a general receiver. 'A furnace of the 
prefent lize has eight flues in all, four of which ierve to 
conduct the fmoke of the cavity to the condenfer ; tite 
other four are (imply mounted with dampers, for alter¬ 
nately forcing the fmoke of the fuel into the vault iV], 
and for admitting the free circulation of air neceliary to 
maintain the combuftion on the grates. In operating 
with furnaces of this conftrnclion, I lhall remark upon the 
tvhole, that, when the furnace wiih.out the condenfing 
apparatus is ufed, the cokes preparing in the interior of 
the furnace ought to be expofed fome hours after tlie 
fmoke hasdifappeared ; but the necelfary length of time 
will immediately depend upon the quantity of the coal 
fubmitted to be coaked. The fame precaution is nqcef- 
fary in iifing the condenfing furnace-; for tills end all 
the dampers ouglit to be opened, and retnain fo for 
a conliderable fpace after the Imoke and vapour liave dif¬ 
appeared. 
An improved fmelting furnace has been lately projeft- 
ed by Mr. Birch, of Abeniant, in Giamorganfhire; which 
received the famStion of his majefty’s letters patent, dated 
April 6, 1802; and of which the following is a deferip- 
tion : “ I the faid James Birch, do hereby deferibe and 
afeertain the nature of my invention, and the manner in 
which the fame is to be performed, by the plan and ele¬ 
vation annexed, and exemplified in the Furnace Plate III. 
the different views in which are all marked with the fame 
CGrrefponding letters. 
Fig. I, reprefents a front elevation of the furnace, and 
its two caft-hoiifes. A, the (lack of the furnace. B, B, 
the two caft-houfes. C, the bridge-houfe. a, a, the 
two new-invented tuyeres. 
b'ig. 2, an end view of the fame furnace and caft-houfes. 
A, the ftack of the furnace. B, the caft-houfe. C, the 
bridge-houfe. 
Fig- 3i ground.plan of the furnace and caft-houfes. 
A, the ftack of the furnace. B, B, the two caft-houfes. 
e,a, the two new-invented tuyeres; b,b, the two new- 
invented tymps; c, tlie hearth wherein the metal is con¬ 
tained ; dddvio. dd the two beds of pigs recetitly caft ; f, f\ 
the two new-invented biowing-pipes. 
Fig. 4, gives the ledfion of tiie furnace-ftack, ftiewing 
the two new.invented ty.mps and tuyeres. A, A, the 
outlide walls of the furnace-ftack ; a, a, the two new- 
invented tuyeres; b, b, the two new-iiivented tymps; c, 
the hearth wherein the nietaji is comained ; e, the infide 
■of the fiirnace-llack. Paris of the furnace, as heretofore 
conftrudled, are alfo introduced, for the purpole of more 
accurately explaining the faid invention, which conlifts 
chiefly in the application of two tuyeres on the fame fide, 
and two tymps oppolite each other, as (hewn in the en¬ 
graving. By this invention a nuicii greater unaiitity of 
iron may be made out of one furnace with leis materials 
than heretofore, and with lefs blaft, and a power will 
likewife be obtained of always making tlie iron belter in 
quality.” 
A patent for a Philofophical P'urnace and Boiler, has alfo 
been granted to Mr. William Raley, of Newbald in 
Yorkfhire, which he deferibes thus: “ I William Raley 
do declare, that my invention is defcrlbed in manner fol- 
Voh. VijI. Mo. 490. 
lowing; that is fo fay : The above-mentioned boiler, of 
any (ize, is made of copper, iron, or other metal, as 
thought proper; the form or fliape of which is either cir¬ 
cular, fquare, cfblong, or oilierwife, as may be found ne- 
ceffary, or moft convenient. Tlic dimenfions of the boiler 
may be in the following proportions, viz fuppolc a cir¬ 
cular or round boiler is fix feet high or deep, from its top 
or rim, which refts or hangs on the furnace ; its width or 
diameter at its top or rim, five feet; and its diameter at 
bottom, three feet ; adding about one foot and a half 
more, in height, (above its ritu,) for tlie convex or outer 
}iart of its cover, as in common boilers for fleam-en¬ 
gines. And, v;ith an intent to increafe the quantity or 
force of fleam, the whole, or as much as polfible, of the 
itifide of the boib-r (above the level qf the water in its 
bottom) is to be kept wet with water, by means of cer¬ 
tain ceils, cavities, aquedudts, troughs, tubes, or oilier 
contrivances, being placed in the infide of the boiler, to 
contain a qu.tr.tity of water above the level of tliat in its 
bottom. And, to convey the laid water to the extremity 
of the infide of the boiler, above the level of tliar in its 
bottom, a contrivance with cells is effedted in the follow, 
ing manner, viz. divide the whole circumfeience or imicr 
extremity of tiie boiler, (from its top to ilie bottom,) in¬ 
to a number of equal jiaris or divifions, by narrow pieces 
ofcoppei, ■ (or other metal,) from one to four inches 
broad, or more, according to the (ize of the boiler ; which 
pieces arc to' be fixed ;o its fides: the miniVer of the 
iibove-iuentioned parts or divifions may be from eight to 
fixteen, more or lefs, according to the fize of the boiler. 
In each of tiief'e divifions (beginning near the top or rim 
of the boiler) are placed pieces of thin copper, or other 
metal, each piece reacliihg from one paitition to another ; 
which pieces ftand perpendicular edge-wife round the in¬ 
fide of tlie boiler: the bottom or lower edge of which 
pieces are joined to, of brought into centadt with, tiie in¬ 
fide of the boiler, fo as to form a circle, or kind of hoop, 
round the extremity of the infide of the boiler. Hence, 
tlie above-mentioned thin pieces of copper, or other me¬ 
tal, being thus arranged, form a kind of ceils, fo as to 
contain a portion of water in each cell. The above-men¬ 
tioned circular or hoop-like arrangement of cells, mould 
be continued, at certain diftances, from near the top or 
rim of the boiler, down to its bottom, or nearly fo. At 
the end of each of the above-mentioned cells, clofe to 
each partition, is a frnall liole to let out the water, fo that 
it may fall into another circle or hoop-like arrangement of 
cells, placed below. Thefe holes are at one eiidof tliofe 
cells, contained in one circular or hoop-iike arrangement 
thereof, and at the other end of thofe contained in the 
next circle, &c. Hence tlie water, in its defeent, runs 
firft one way and then the other, thereby forming a kind 
of ferpentine motion in each divifion. The diftance thefe 
circular arrangements of cells are one from the other, may 
be about one foot, more or lefs, according to the fize of 
the boiler. In cafe they are at the diftance of one foot, 
the thin pieces of copper, or other metal, need only be 
about half a foot broad. The above-mentioned cells are 
fupplied with water, either from that within the boiler, 
or from fome refervoir, or other containing veffel, on the 
outfide thereof. They are fupplied with water front 
without the -boiler, by tubes from a clofe refervoir of wa. 
ter, placed a convenieq.t height above the level of the 
boiler; each tube having.a cock, or kind of valve, fo as 
to let a due quantity of water into the cells in each divi- 
fion, within :he boiler. A (team-tube is placed from the 
laid dole refervoir to the boiler, to preferve an equal ba¬ 
lance of power of the (team in each of the two veffels. 
'i'he above-mentioned clofe refervoir may (for a boiler of 
the fame dimenfions) be about one foot aiiu a half itigh or 
deep, three feet in diaiiieter at its top, and two feet and a 
half in diameter at its bottom. The water is thrown 
either into the clofe refervoir, or boiler, by a, pump, 
worked by the force of (team, or otherwife, (from the hof 
Oo well, 
