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r tning. which can be t:1k~n ir or put 00 at r1e;¡ftJIr ; Ly
""llIeh the whole air thJ1 cnr::rs ¡nlU lhe chimney is m,u.J( lO
p ..rs lhlOUgh the (¡re like a furnMe, :.:nd c" fries lhe flUllkc
\~P ir wtth gua! velocl1 )' Tlu fe:: ¡r~ wcll kno\\'n In 1.lfCe
(0\1,.'05 by lhe Iltlmc ¡ind,"" illll.CJ1: hUl as thl'Y occ. fion a
a proJigious waHe of (e\Vd WitlHlUl \\a rming th::: room. ando
"Dlels aHended witll \'ery great CM -':, :are In d. ngl.:r of fe\ –
rinl! (he building on li re. ¡hey oncht to be as mUl..h 2voided
=-s plJffible BUI ir o,ilher this, nor an)' of lhe othcr me·
rhods pro\'c cff"étual, (he \\.all muH eit hcr he takcn down
and rebuilt in a proper manner, Or the chimney ílbandoned
a$ iocl!r:lble. As this is a dcft.é'l more ddncult to be teme·
d:cd than any othcr, we wonld Clrongly'recommcnd ¡tlO enry
btlilder to build his chimnt'}'S of .J. (uClicicnt wit.lth through.
c;>ut ; there is no daugu of en ¡og Oll ,his extremc, as it is
eafy fO rcmedy 30y dde\.'l: Ih"l mif~t arifc froIU jI.
4th,. As the air which af..::cnds through ~he chlmney con·
.ioues neuly of an equal dC'glC~e of heat 10 lhe IOp, lhe
tube lhould be of an equ. 1 decr<e of widlh al lhe lO!, as al
,he bottom, as well as throug,h the \\'hole of iu length .
I I ought nOl therl"rore 10 be n1ade taperín~ gradually IroOl
Ihe 6re· place lO lhe top. bUI lO be (uddenly eontr.tled a·
hove lhe grale, as in fig. 6. {rom which il ousbt to be ~on­
tinued of 20 cqual wident'fs throu~hout iu whole lenglh;
hUI if il is narrower at any one place thAn another, il ought
10 be at lhe under pan, immedi.ltcly above lhe "re, for a
'Yery (hon fpace; b<:c=lufe, as this is within re.lch of the hanJ,
the root cae be·cleaned from it as often as is ncceíf;r,r)'. Co
that when lhe other pJrtS of lhe chimney are fuI! and
clogged ",ilh fOOl, lhey ",ill nOI be narro",:r lhan lhis place
is at that time.
51h, !t fcldom happens lha< a ehimney can be carried
'lulte Clrajcbt upwards : and jt is an advantage that it i.s fo,
os lhey ough, al\Vays lO be bcnl a linle. fur if a ehimney
be fl raigh" and of il propcr wichh to tranfmit the wholt: 01
the fmoke and no more, it will not be fufficien t for th u
purpore, when there i~ a hl!avy f~1I ol' rain. or fnow, or
haiJ, .'¡lh litrle wind ¡ for lhe great rlrops will fall perpen·
dicul:..r1y (.om the (0 0 lO the boltom'of the chimnel; and
as lhey oecupy a e~nfidc,"ble (pace, lhe fmoke will no'
llave room lO afcend, but muí\: ue foreed down with the
fhowcr, and d;fpe!red in lhe aparl ment: whereas, ir che ehim~
n"y is ben" lhe raio f.lls upon (om, of ,he fides , and glide.
g<ndy down wilhou, diOurbing Ihe afecnl o( ,he (moke.
The rame inconvc:nience will be fdt in a flr.lIgh t chimney,
1Vhere it is fo placed as to be expofed tO winds, which
(ometimes enter lhe tOP and blow down with a rudden puff:
for, ir it be Clraight, th\! air meets Wi lh no illtl.rru ption tili
it dc[cendi3 ¡otO lhe chambcr, and ther..: tlirpcrrc:s lhe fOloke;
bUl if il be crooked. ,he defeenl of lhe wind will be ob
fl rutled . ilS force broken, ¡lOd lhe dfd h of il in a
grcat mearure prevented . U pon the wholc:. bl.!nt chimneys
Rje aJways preferable to Ilraight ones. H \Jwever, a perpen
d,eular ehimney may be e.fily cured, by (ome o( lhe con·
trivanee...fter mentioned . .
Thefe are lhe moll gener.1 dcfd h arifill g (rom lhe Orue·
tnre of the chimney ¡t[t lf. which are al! reJucible to the
feAlowing caufes : f. T ol') JíttJe heighl; 2 . T ('J grea[
widenefs of Ihe bottom of the chí,nOl:y ; 3. T oo ¡iuh:
width; 4 Unequ.d wi~cncfs bct\veen lhe tOr and bOllom ;
and, 5. Strlighloers o( ,he tube. \VI.! : po:ntcJ out
L'te bcll ",",hoó, of c" rins eaeh 01" lhefe dcf,(ts ; anJ lO fi·
S ~l O
nini ('ur rcmíll "S on this ~cner:ll lIeao, ancl ~i\'c tlie r{,íldcr
a more pafltt ulca of Ihe: bdl (urm of CO:I!trll(tI'Jn for a
chimnl y. \Ve: llave dr;¡wn n ...o difraent (dlioos uf Ojl\! con.
Ilruét ...u 00 lhe: ¡ulle!! principIe" In f'guJ <'s 6. iino 7. lhe fe.
ver.d p:lTts of whlch . rpcar fo "Llin In,m ,I,e figures. anu
l h~ n:afuns fur ,his cunllruélion have becn aiready ro Clt :H~
Iy :4lTi 6 ned. t1\jU a vc:r)' filMt CX¡,!ilnat:un \ViII be fufficl cllt.
Flg.ure 6. rcprefrnts '" frnnt.view (¡f the fire.plac,,: ; f,.p_
pollng lh: forc.p.\rt of the WJII t",ken down, and th\! chim.
neyJald bare(rom IOp tObotlom¡ AH. and De, rcprcrentinc
the 1\VO (¡des of fhe fire. place; and Be, 'he: nunde, briag
through, lO fhew lhe m;;.nner in whieh the 2pt nun: 1$
fudde:nly cuntr<ttlcd. immedi:ueJy ~bove ,he fi re vút!Jin the
mande . The tube from tht: point E , lO the top, OtlJth l to
be of ao equ~1 wident:r" aud bent in aoy dlre6 ion {hat m<l.y
be convenienL The: 1\YO piAnes, f F, rtprcft nt lhe t'NO (¡des
of the fire_plare, which ought to be as Oluch Cloped inward
IOwards the back as the 101m 01 the grate will admit of ;
(or lhe more lhey :.re inclilled, lhe more: powe:-f~lI y wtll
they refletl the ne<l.t into lhe apartmcnt . Fig. 7. reprcfcnls
a perpeodicllJar [e{lion of the wall, throllgh \h~ middlc of
the chimney, to difcover its fhape. if vtewed (rum a fideo
And here It is lO be obferved , that it ought e"er to be a rúle
to bring lhe building al the unJt:r pHt uf lhe chiOlney im·
Illtdiately behind lhe: grate, as fa r forwHd as pollible,
becaufe this throws more heat the ch:\mbcr than if jt
Wt re pl.\ced farther back: but as lhe fore-pJrt of lhe gra:e
ought never 10 proj,d l bc:yond the inn<:r edge of the m.tntl<:,
care: fhould be taken tO have lhe unde r pan of rhe m:lntle
wrought as thin as lhe nature of the materÍ;ds \VI :! admit
of, m:4king it \hicker lowards the uppe r parto [ti oI.S lO Oope
iDwards ab.lve the fire, as repreCenteu at H. fiJ~. 7. 1'0
throw the heat oUlward, Jet d,e upper pa n or the ba:k of
lhe fire~place be a Htlle inclined oUl\Yard, as al e: bUl, af.
ter ir is carried up iOn t!lis a little higher than 1he
m¡ntle. Jet il be fuddenly turned back, as in lhe (itiure, lhe
projeélion aboYe lhe mande inclining backward in lh~ fame
direélion, being carried up lO the top at an equaJ widcnels
lhe whole way.
Although it is necelfary to I~ave all chimneys prett y
wide; yet this. on many occaGons, is auended with incon.
veniences : fo r as they tranfmit a great quan.i, }' o." heJted
air, too la.rge a portion of that warm air wh:ch ought 10
he.l che chamber is carrlzd off; aud as it is only whcn lhe
6re is fidl kindled t.hal Ihe grcat quantilY of &\'015 vapour
is exhaled which fills lhe chimney, aod makelh el ¡"'ge tubc
nece{f,Hy, if it were fo contriv<:d as 10 contrall. or ¿".He at
pleafurt , \Ve m:ght hJve our chimney of a CulFicient widlh
lO convcy away li,e gr(atd t qu.mlity of fll\(" kc that couhl
ever h:we uccafion to pd(S through ¡t, íit Ihe fimll! tim.!
that \Ve might ncver :1110\'1 more air 10 pafs off at other limes
lhan w"s nccdrúry tO C;lrlY awtty the u·hole.: of the fmokt!'.
by which mcans a Oluch fmaller q'Jlnlity of fewcl \\'oulJ
kecp our apa rtment cqually warm. This we arprehen\l
Olight be accomr1dhe:d by the folJowing fimple api'.tratu3 .
L ::t a fh c..:t of D1dl~d iron be fi xcd.H Ih(' ur rcr rart 01 Ihe
l11J.ntlc, on Ihc infidc, oH B, in fu~h a manner, as lh,u,' by
means of a (m. 1I wire dr, paffing lhrough a fmall hole I<f,
for thu Illlrpofe in the forc:.p.lrt of the: chimncy, jl mig:lt
be let clown at plca(urc tO\'lArds C. or up 10\\'anh
B. fo " 10 apply quile clo(e lO lhe upper cdg< uf lh~.
\..himncy bctwecn U anu e. T h:s le.\\'c t!l'Z :ube ni
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