,,common ,,commodities ,,& ,,indu/ries ,,s]ies ,ea* book 9 cr[n #hvo1 clo?1 ) _m illu/rations1 *>ts1 etc41 #b_/f net ,,tea4 ,by ,a4 ,ibbetson ,,c(fee4 ,by ,b4 ,b4 ,keable ,,sug>4 ,by ,geo4 ,m>t9eau1 ,c4,b4 ,,oils4 ,by ,c4 ,a9swor? ,mit*ell1 ,b4,a41 ,f4,i4,c4 ,,:eat4 ,by ,&rew ,mill> ,,rubb]4 ,by ,c4 ,beadle & ,h4 ,p4 ,/ev5s1 ,m4,a41 ,ph4,d41 ,f4,i4,c4 ,,iron ,,& ,,/eel4 ,by ,c4 ,hood ,,copp]4 ,by ,h4 ,k4 ,pic>d ,,coal4 ,by ,francis ,h4 ,wilson1 ,m4,in/41 ,m4,e4 ,,timb]4 ,by ,w4 ,bullock ,,cotton4 ,by ,r4 ,j4 ,peake ,,silk4 ,by ,lu!r ,hoop] ,,wool4 ,by ,j4 ,a4 ,hunt] ,,l954 ,by ,alfr$ ,s4 ,moore ,,tobacco4 ,by ,a4 ,e4 ,tann] ,,lea!r4 ,by ,k4 ,j4 ,adcock ,,knitt$ ,,fabrics4 ,by ,j4 ,*amb]la9 & ,j4 ,h4 ,quilt] ,,clays4 ,by ,alfr$ ,b4 ,se>le ,,pap]4 ,by ,h>ry ,a4 ,maddox ,,soap4 ,by ,william ,a4 ,simmons1 ,b4,sc4 7,lond471 ,f4,c4,s4 ,,! ,,motor ,,indu/ry4 ,by ,horace ,wyatt1 ,b4,a4 ,,glass ,,& ,,glass ,,mak+4 ,by ,p]cival ,m>son ,,gums ,,& ,,res9s4 ,by ,e4 ,j4 ,p>ry1 ,b4,sc41 ,f4,i4,c41 ,f4,c4,s4 ,,! ,,boot ,,& ,,%oe ,,indu/ry4 ,by ,j4 ,s4 ,h>d+ ,,gas ,,& ,,gas ,,mak+4 ,by ,w4 ,h4 ,y4 ,webb] ,,furniture4 ,by ,h4 ,e4 ,b9/ead ,,coal ,,t>4 ,by ,a4 ,r4 ,w>nes ,,petroleum4 ,by ,a4 ,lidgett ,,salt4 ,by ,a4 ,f4 ,calv]t ,,z9c4 ,by ,t4 ,e4 ,lones1 ,m4,a41 ,,ll4,d41 ,b4,sc4 ,,photography4 ,by ,wm4 ,gamble ,,asbe/os4 ,by ,a4 ,leon>d ,summ]s ,,silv]4 ,by ,b5jam9 ,:ite ,,c>pets4 ,by ,reg9ald ,s4 ,br9ton ,,pa9ts ,,& ,,v>ni%es4 ,by ,a4 ,s4 ,j5n+s ,,cordage ,,& ,,cordage ,,hemp ,,& ,,fibres4 ,by ,t4 ,woodh\se & ,p4 ,kilg\r ,,acids ,,& ,,alkalis4 ,by ,g4 ,h4 ,j4 ,adlam ,,o!rs ,,9 ,,prep>ation ,illu/ration3 ,copyright by ,messrs ,flatt]s ,g>nett1 ,man*e/] ,,bact]ia ,,nodules ,,on ,,! ,,root ,,( ,,lup9 ,,pitman',s ,,common ,,commodities ,,& ,,indu/ries ,,acids1 ,,alkalis ,,& ,,salts ,,by ,g4 ,h4 ,j4 ,,adlam1 ,m4,a41 ,b4,sc41 ,f4,c4,s4 ,editor ( 8,! ,s*ool ,sci5ce ,review0 ,london ,sir ,isaac ,pitman ,sons1 ,ltd41 #a ,am5 ,corn]1 ,e4,c4#d ,ba?1 ,melb\rne & ,new ,york ,pr9t$ by ,sir ,isaac ,pitman ,sons1 ,ltd41 ,london1 ,ba?1 ,melb\rne & ,new ,york ,,preface ,x has (t5 be5 said1 & /ill m (t5 impli$1 t consid]ations ( utility 9 education are incompatible ) its ma9 object1 :i* is ! tra9+ ( ! m9d4 ,extremely div]g5t views h be5 express$ on ?is po9t4 ,s*oolm5 h look$ askance at "s bran*es ( k because !y 7 suppos$ to be ta9t$ ) ! possibility ( usefulness 9 aft] life4 ,on ! o!r h&1 bus9ess m5 & o!rs h compla9$ bitt]ly ( ! pres5t /ate ( education because v little t is consid]$ 8useful0 has up to ! pres5t be5 taught 9 s*ools4 ,x is possible to err 9 bo? directions4 ,a univ]sity pr(essor1 lectur+ on high] ,ma!matics1 is report$ to h told 8 audi5ce t x 0 a s\rce ( great satisfaction to him t ! !orem :i* he 0 demon/rat+ c\ld nev] be appli$ to any?+ 8useful40 ,on ! o!r h&1 we h ! well-au!nticat$ /ory ( ! man :o took 8 son to ! ,royal ,s*ool ( ,m9es to 8le>n copp]10 & n to wa/e 8 "t ov] o!r p>ts ( ,*emi/ry1 because 8!y w\ld be ( no use to him40 ,= n>r[ness ( outlook1 !re is no?+ to *oose betwe5 ! p$ant & ! 8practical0 man4 ,national education w\ld det]iorate if its control %\ld ev] pass into ! h&s ( extremi/s ( ei!r type1 = no?+ wor?y ( ! "n ( education c\ld ev] be giv5 or receiv$ 9 su* an irrational _s4 ,9 deal+ ) ! subject ( 8,acids1 ,alkalis1 & ,salts10 ,i h endeav\r$ to give prom95ce to ! comm]cial & dome/ic importance ( ! sub/ances dealt )4 ,i !reby hope to ga9 ! int]e/ ( ! read]1 s9ce int]e/ /&s 9 ! same relation to education t petrol does to ! motor-c>4 ,x is n education itself1 b x is ! s\rce ( its motive p[]4 ,i h also includ$ "s consid]ations ( a !oretical nature :i* may well be tak5 z a fir/ /ep t[>ds ! cont9uation ( ! /udy ( ,*emi/ry4 ,my s9c]e ?anks are (f]$ to my colleagues1 ,f4 ,w4 ,g4 ,foat1 ,m4,a41 ,d4,litt41 & ,mr4 ,i4 ,s4 ,sc>f1 ,f4,i4,c41 = mu* valuable help & advice2 to ,sir ,edw>d ,?orpe1 ,c4,b41 ,f4,r4,s41 & ,messrs4 ,william ,coll9s ,sons = p]mission to reproduce ,figures #c1 #aa1 & #ad2 to ,messrs4 ,longmans ,co4 = ,figures #d1 #e1 #i1 #ab1 #ac1 #af2 ,messrs4 ,macmillan ,co41 = ,figures #h1 #aj & #ae4 ,i h also avail$ myself ( ! assi/ance ( sev]al /&>d works on ,*emi/ry4 ,my ackn[l$gm5ts 9 ?is direction take ! practical =m ( ! %ort bibliography :i* foll[s-- ,lunge1 ,dr4 ,g4 ,! ,manufacture ( ,sulphuric ,acid & ,alkali4 ,vols4 ,i1 ,,ii1 & ,,iii4 ,roscoe ,s*orlemm] ,treatise on ,*emi/ry4 ,vol4 ,i4 ,! ,non-metallic ,elem5ts 7#aiaa74 ,vol4 ,,ii4 ,! ,metals 7#aiac74 ,brannt1 ,w4 ,t4 ,! ,manufacture ( ,v9eg> & ,acetates4 ,?orp1 ,f4 ,h4 ,outl9es ( ,indu/rial ,*emi/ry 7#aiac74 ,?orpe1 ,t4 ,e4 ,a ,manual ( ,inorganic ,*emi/ry4 ,new?1 ,g4 ,s4 ,a ,text-book ( ,inorganic ,*emi/ry4 ,mellor1 ,j4 ,w4 ,mod]n ,inorganic ,*emi/ry4 ,coh51 ,j4 ,b4 ,!oretical ,organic ,*emi/ry4 ,g4 ,h4 ,j4 ,a4 ,city ( ,london ,s*ool1 ,e4,c4 ,,cont5ts ,,*ap4 ,,page ,,preface v ,i4 ,,introduction #a ,,ii4 ,,sulphuric ,,acid ,,& ,,sulphates #aj ,,iii4 ,,nitric ,,acid ,,& ,,nitrates #bh ,,iv4 ,,! ,,halog5 ,,acids #dc ,v4 ,,c>bonic ,,acid ,,& ,,c>bonates #di ,,vi4 ,,phosphoric1 ,,boric1 ,,& ,,silicic ,,acids #ef ,,vii4 ,,organic ,,acids #fg ,,viii4 ,,mild ,,alkali #hj ,,ix4 ,,cau/ic ,,alkalis #ie ,x4 ,,electrolytic ,,me?ods #aja ,,index #aji ,,illu/rations ,,fig4 ,,page ,,bact]ia ,,nodules ,,on ,,! ,,root ,,( ,,lup9 ,frontispiece #a4 ,,diagram #g #b4 ,,plan ,,( ,,sulphuric ,,acid ,,works #ac #c4 ,,g5]al ,,view ,,( ,,sulphuric ,,acid ,,works #ae #d4 ,,sulphur ,,trioxide--,,! ,,contact ,,process #ai #e4 ,,prep>ation ,,( ,,nitric ,,acid #cj #f4 ,,nitrog5 ,,cycle 7,,diagram7 #ch #g4 ,,nitric ,,acid ,,f ,,air 7,,diagram7 #da #h4 ,,prep>ation ,,( ,,hydro*loric ,,acid #de #i4 ,,boric ,,acid #ei #aj4 ,,quick ,,v9eg> ,,process #ga #aa4 ,,dut* ,,process ,,= ,,:ite ,,lead #gd #ab4 ,,salt ,,cake ,,furnace #hc #ac4 ,,black ,,a% ,,furnace #he #ad4 ,,! ,,solvay ,,process #hi #ae4 ,,! ,,electrolysis ,,( ,,salt ,,solution #ajb #af4 ,,! ,,ca/n] ,,process #aje ,,acids1 ,,alkalis1 ,,& ,,salts ,,*apt] ,i ,,introduction ,acids4 ,a vague h9t f ,nature gave mank9d ! fir/ indication ( ! exi/5ce ( acids4 ,! juice press$ f ripe grapes is a sweeti% liquid4 ,if x is kept = "s "t1 ! sweetness goes1 & ! liquid acquires a burn+ ta/e4 ,if kept /ill long]1 ! burn+ ta/e is lo/1 & 9 its place a %>p acid flav\r1 n entirely displeas+ to ! palate1 is develop$4 ,! liquid obta9$ 9 ?is way is n[ call$ w9e v9eg>2 ! p>ticul> sub/ance :i* gives x its *>act]i/ic ta/e is acetic acid4 ,! /ronge/ v9eg> does n conta9 m ?an #aj p] c5t4 ( acetic acid1 :i* is itself a comp>atively weak acid4 ,x is1 !re=e1 n a v active solv5t4 ,nev]!less1 = metals & = lime/one rock1 & o!r sub/ances ( a calc>e\s nature1 its solv5t p[] is great] ?an t ( any o!r liquid kn[n at ! "t ( its discov]y4 ,x 0 ?is prop]ty :i* seems to h appeal$ mo/ /rongly to ! imag9ation ( ! e>ly *emi/s2 &1 z is v (t5 ! case1 ! description ( its p[]s 0 v mu* exagg]at$4 ,livy & ,plut>*1 :o h giv5 u an acc\nt ( ,hannibal's invasion ( ,italy by way ( ! ,alps1 bo? gravely decl>e t ! ,c>?ag9ian lead] cle>$ a passage = 8 elephants ?r\gh solid rocks by p\r+ v9eg> ov] !m6 ,9 ! ,middle ,ages1 ! /udy ( ,*emi/ry 0 fo/]$ ma9ly z a possible means :]eby long life & untold ri*es might be obta9$4 ,! 8,philosoph]'s ,/one10 by ! ag5cy ( :i* ! base metals 7 to be *ang$ to gold1 & ! 8,elixir ( ,life10 :i* 0 to bani% disease & dea?1 7 eag]ly s\ght =4 ,?\gh ^! 7 va9 imag9+s accord+ to mod]n ideas1 nev]!less !y 7 p[]ful inc5tives t[>ds exp]im5tal "w4 ,_m new sub/ances 7 discov]$ 9 ?is p]iod1 & among ^! 7 nitric acid 7aqua =tis71 hydro*loric acid 7_s ( salt71 & sulphuric acid 7oil ( vitriol74 ,acids 7 !n valu$ above all o!r sub/ances4 ,! m$iaeval *emi/ 7or al*emi/1 z he 0 call$7 cle>ly saw t unless a body c\ld be dissolv$ up !re 0 no hope ( *ang+ x4 ,nitric acid1 !re=e1 :i*1 9 conjunction ) hydro*loric acid1 dissolv$ ev5 gold itself1 0 v highly e/eem$4 ,oil ( vitriol also 0 sc>cely less important1 = x 0 requir$ = ! production ( o!r acids4 ,s f>1 ta/e & solv5t p[] 7 consid]$ to be ! *>act]i/ic feature ( acids4 ,9 ! "t ( ,rob]t ,boyle 7#afbg-afia71 !y 7 fur!r di/+ui%$ f o!r sub/ances by ! *ange :i* !y produc$ 9 ! col\r ( c]ta9 vegetable extracts4 ,t9cture ( r$ cabbage 0 fir/ us$1 b1 z ?is liquid rapidly det]iorates on keep+1 x 0 soon replac$ by a solution ( litmus1 a col\r+ matt] obta9$ f ,roccella t9ctoria & o!r li*5s4 ,x imp>ts to wat] a purple col\r1 :i* is *ang$ to r$ by ! addition ( acids4 ,alkalis4 ,wood a%es 7 valu$ 9 v e>ly times because !y 7 f\nd to be good = remov+ dirt f ! sk94 ,mix$ ) vegetable oil or animal fat1 !y =m$ a v primitive k9d ( soap1 :i* 0 aft]w>ds mu* improv$ by us+ ! aque\s extract in/ead ( ! a%es !mselves1 & also by ! addition ( a little cau/ic lime4 ,:5 plant a%es are treat$ ) wat]1 ab\t #aj p] c5t4 dissolves4 ,if ! insoluble matt] is !n all[$ to settle d[n & ! cle> liquid evaporat$ to dryness1 a :iti% residue is obta9$4 ,! soluble matt] ?us extract$ f ! a%es ( plants :i* gr[ 9 or ne> ! sea is ma9ly soda2 t f l& plants1 ma9ly pota%4 ,=m]ly no di/9ction 0 made1 & ! g5]al t]m 8alkali0 0 appli$ to bo?4 ,9 ord] to br+ ! prop]ties ( alkalis into contra/ ) ^? ( acids1 we _c d bett] ?an make a few simple exp]im5ts ) a weak solution ( wa%+ soda4 ,its ta/e is v diff]5t f t ( an acid2 x is g5]ally describ$ z cau/ic4 ,if a little is rubb$ betwe5 ! f+]s1 x feels smoo?1 almo/ l v ?9 oil4 ,x does n dissolve metals or lime/one4 ,its action on vegetable col\r+ matt] is j z /rik+ z t ( acids4 ,t9cture ( r$ cabbage becomes gre52 ! purple ( litmus is *ang$ to a light blue4 ,?is col\r *ange is *>act]i/ic ( alkalis4 ,neutralization4 ,:5 ! col\r ( litmus solution has be5 *ang$ to r$ by ! addition ( an acid1 ! orig9al col\r c be re/or$ by add+ an alkali4 ,! *ange c be repeat$ z (t5 z desir$ by add+ acid & alkali alt]nately4 ,f ?is we get a di/9ct impression ( anti!sis betwe5 ! two4 ,9 popul> language1 an alkali 8kills0 an acid2 9 ,*emi/ry1 ! same idea is express$ by ! t]m 8neutralization40 ,salts4 ,bo? 8neutralization0 & 8kill+ ! acid0 are modes ( expression :i* describe ! ph5om5on fairly well4 ,:5 an acid is neutraliz$1 its *>act]i/ic ta/e1 its solv5t p[]1 & its action on litmus1 are all *ang$2 9 fact1 ! acid z an acid ceases to exi/1 & s does ! alkali4 ,:5 ! neutral solution is evaporat$ to dryness1 a residue is f\nd :i* on exam9ation proves to be nei!r ! acid nor ! alkali1 b a comp\nd =m$ f ! two4 ,?is sub/ance is call$ a salt4 ,to mo/ p1 salt is ! "n = t p>ticul> sub/ance :i* is tak5 z a condim5t ) food4 ,its use 9 ?is connection dates f "t immemorial4 ,x is di/9ctly un=tunate t ano!r & v mu* wid] usage ( ! t]m has be5 introduc$ into ,*emi/ry4 ,:5 ! e>ly *emi/s recogniz$ t o!r sub/ances1 :i* !y vaguely designat$ z 8sal9e bodies10 7 simil> to common salt 9 composition1 !y took ! "n ( ! individual & appli$ x to ! :ole class4 ,,o!r ,,me?ods ,,( ,,salt ,,=mation ,solution ( ,metals 9 ,acids4 ,alkalis are n ! only sub/ances :i* neutralize acids4 ,speak+ 9 a broad & g5]al s5se1 we may say t an acid is neutraliz$ :5 a metal is dissolv$ 9 x1 because1 :5 ! po9t is rea*$ at :i* no m metal w dissolve1 all ! *>act]i/ic prop]ties ( ! acid are de/roy$4 ,a salt is =m$ 9 ?is case also4 ,an example w n[ be giv5 to illu/rate ?is me?od ( salt =mation4 ,be=e two pieces ( metal c be unit$ by sold]+1 x is necess>y to clean ! surfaces ( ! metal & ! sold]+ iron4 ,! liquid us$ = ?is purpose is made by add+ scraps ( z9c to muriatic acid 7hydro*loric acid74 ,! z9c dissolves ) eff]vesc5ce1 :i* is caus$ by ! escape ( hydrog5 gas4 ,:5 eff]vesc5ce ceases & no m z9c w dissolve1 ! liquid is ready = use4 ,! acid has be5 8kill$0 or neutraliz$ by ! metal4 ,a salt call$ z9c *loride has be5 =m$4 ,?is salt c be recov]$ f ! liquid by evaporation4 ,solution ( ,oxides 9 ,acids4 ,! sub/ances mo/ us$ 9 comm]ce ) ! express purpose ( de/roy+ acidity are quicklime1 wa%+ soda1 & p[d]$ *alk4 ,s9ce quicklime is a comp\nd ( ! metal calcium & ! gas oxyg51 its sy/ematic "n is calcium oxide2 :5 x neutralizes an acid1 x =ms ! correspond+ calcium salt2 = example1 if x neutralizes acetic acid1 calcium acetate is =m$4 ,an in/ance ( ! neutralization ( an acid by an oxide ( a metal is furni%$ by "o me?od ( prep>+ blue vitriol 7copp] sulphate74 ,copp] does n dissolve v quickly 9 dilute sulphuric acid2 h5ce1 to make blue vitriol f scrap copp]1 ! metal is fir/ heat$ v /rongly :ile freely expos$ to air4 ,copp] & oxyg5 ( ! air comb9e to =m ! br[ni% black p[d]1 copp] oxide1 & ?is dissolves v readily 9 sulphuric acid1 mak+ ! salt1 copp] sulphate4 ,solution ( ,c>bonates 9 ,acids4 ,wa%+ soda & *alk belong to a diff]5t class ( *emical sub/ances4 ,!y are c>bonates1 t is1 !y are salts ( c>bonic acid4 ,at fir/ x may seem a little p]plex+ to ! read] to le>n t a salt c neutralize an acid to =m a salt4 ,x mu/ be rememb]$1 h[ev]1 t acids diff] f "o ano!r 9 /r5g?1 t is1 9 *emical activity1 & t c>bonic acid is a weak acid4 ,:5 a salt ( c>bonic acid--sodium c>bonate or wa%+ soda1 = example--is add$ to a /rong] acid su* z sulphuric acid1 sodium sulphate is =m$ & c>bon dioxide lib]at$4 ,z an example ( ! neutralization ( acids by c>bonates1 we may m5tion "h a practical sug> sav+ device4 ,unripe fruit is v s\r because x conta9s c]ta9 vegetable acids dissolv$ 9 ! juice4 ,^! acids are n affect$ by boil+2 &1 !re=e1 to make a di% ( /ew$ fruit palatable1 x is necess>y to add sug> 9 quantity suffici5t to mask ! s\r ta/e4 ,if a p9* ( bic>bonate ( soda is add$ to neutralize ! acid1 f> less sug> w be necess>y = sweet5+4 ,insoluble ,salts4 ,! me?ods giv5 above apply only to ^? salts :i* are soluble 9 wat]4 ,insoluble salts are obta9$ by mix+ two solutions1 ! "o conta9+ a soluble salt ( ! metal1 & ! o!r1 a soluble salt ( ! acid or ! acid itself4 ,! =mation ( an insoluble salt by ! int]action ( two soluble sub/ances is well illu/rat$ 9 ! prep>ation ( ,burgundy mixture1 ! mo/ effectual rem$y yet propos$ = *eck+ ! spread ( potato disease4 ,?is mixture conta9s copp] c>bonate1 t is1 ! copp] salt ( c>bonic acid4 ,= its prep>ation we require copp] sulphate & sodium c>bonate 7wa%+ soda71 a soluble c>bonate4 ,:5 ^! two sub/ances1 dissolv$ 9 sep>ate portions ( wat]1 are mix$1 copp] c>bonate is =m$ z a pale blue solid :i* is 9 su* a /ate ( f9e subdivision t x rema9s susp5d$ 9 ! solution ( sodium sulphate1 ! o!r product ( ! reaction4 ,! *ange is repres5t$ diagrammatically bel[4 ,ea* circle repres5ts ! atom or a gr\p ( atoms nam$ !re94 ,at ! mom5t ( mix+1 ^! gr\ps und]go re-arrangem5t4 ,bordeaux mixture1 :i* "s g>d5]s pref]1 is a simil> prep>ation conta9+ copp] hydroxide in/ead ( copp] c>bonate4 ,x is made by mix+ cle> lime wat] 7a soluble hydroxide7 ) copp] sulphate4 ,illu/ration3 ,fig4 #a ,elem5ts & ,comp\nds4 ,x is sc>cely possible to discuss *emical processes )\t hav+ f "t to "t to use t]ms :i* are n 9 ev]yday use4 ,a few prelim9>y def9itions & explanations ( t]ms :i* w be frequ5tly us$ may s]ve to simplify descriptions1 & r5d] x unnecess>y to encumb] !m ) purely explanatory matt]4 ,among ! _m diff]5t k9ds ( mat]ials kn[n1 :i* 9 ! aggregate am\nt to sev]al hundr$s ( ?\s&s1 !re are ab\t n9ety sub/ances :i* up to ! pres5t "t h n be5 brok5 up into simpl] k9ds4 ,^! prim>y mat]ials are call$ 8elem5ts10 ! rema9d] be+ kn[n z 8comp\nds40 ,! foll[+ is a li/ ( ! commone/ ( ^! elem5ts1 toge!r ) ! symbols by :i* !y are repres5t$ 9 ,*emi/ry4 ,,metals ,alum9ium ,al4 ,antimony 7,/ibium7 ,sb4 ,b>ium ,ba4 ,bismu? ,bi4 ,cadmium ,cd4 ,calcium ,ca4 ,*romium ,cr4 ,copp] 7,cuprum7 ,cu4 ,gold 7,aurum7 ,au4 ,iron 7,f]rum7 ,fe4 ,lead 7,plumbum7 ,pb4 ,li?ium ,li4 ,magnesium ,mg4 ,manganese ,mn4 ,m]cury 7,hydr>gyrum7 ,hg4 ,nickel ,ni4 ,plat9um ,pt4 ,potassium 7,kalium7 ,k4 ,silv] 7,arg5tum7 ,ag4 ,sodium 7,natrium7 ,na4 ,/rontium ,sr4 ,t9 7,/annum7 ,sn4 ,z9c ,zn4 ,,non-,,metals ,boron ,b4 ,brom9e ,br4 ,c>bon ,c4 ,*lor9e ,cl4 ,fluor9e ,f4 ,hydrog5 ,h4 ,iod9e ,i4 ,nitrog5 ,n4 ,oxyg5 ,o4 ,phosphorus ,p4 ,silicon ,si4 ,sulphur ,s4 ,! fir/ /ep 9 ! build+-up process consi/s ( ! union ( a metallic ) a non-metallic elem5t4 ,su* comp\nds are b9>y comp\nds1 & are di/+ui%$ by ! t]m9ation -ide add$ to ! "n ( ! non-metallic elem5t2 = example1 copp] & oxyg5 unite to =m copp] oxide1 sodium & *lor9e =m sodium *loride1 iron & sulphur =m iron sulphide or sulphide ( iron4 ,a comp\nd conta9+ m ?an two elem5ts is di/+ui%$ by ! t]m9ation -ate4 ,mo/ salts fall )9 ?is category2 ?us we speak ( acetate ( lead & *lorate ( pota%1 also ( sodium sulphate & copp] sulphate1 ! latt] =m be+ ! m correct4 ,a difficulty arises :5 two bodies are compos$ ( ! same elem5ts comb9$ 9 diff]5t proportions4 ,!n we h to resort to o!r di/+ui%+ prefixes or suffixes4 ,= ?is reason we meet ) sulphurous acid & sulphuric acid1 ! correspond+ salts be+ sulphites & sulphates4 ,cry/als & ,wat] ( ,cry/allization4 ,:5 a soluble salt is to be recov]$ f its solution1 ! latt] is r$uc$ 9 bulk by evaporation until1 ei!r by exp]i5ce or by trial1 x becomes evid5t t ! solid w be =m$ z ! liquid cools4 ,9 "s cases1 :5 "t is n an important factor1 evaporation is left to take place naturally4 ,"u ei!r set ( conditions1 ! sub/ance g5]ally sep>ates out 9 p>ticles :i* h a def9ite geometrical =m4 ,^! are spok5 ( z cry/als4 ,cry/als (t5 conta9 a def9ite p]c5tage ( wat]1 call$ 8wat] ( cry/allization40 ,9 wa%+ soda1 ?is comb9$ wat] =ms ne>ly #fc p] c5t4 ( ! total weight2 9 blue vitriol1 x is approximately #cf p] c5t4 ,on be+ heat$ to a mod]ate temp]ature1 ! wat] is expell$ f ! solid2 ! sub/ance :i* is left beh9d is call$ ! anhydr\s 7t is1 ! wat]less7 salt4 ,,*apt] ,,ii ,,sulphuric ,,acid ,,& ,,sulphates ,key ,indu/ries4 ,! importance ( ! *emical indu/ries dep5ds ma9ly on ! fact t !y con/itute ! fir/ /ep 9 a s]ies ( op]ations by :i* natural products are adapt$ to our ne$s4 ,! mat]ials :i* are f\nd 9 e>?1 air1 & wat] are bo? v>i$ 9 k9d & abundant 9 quantity1 b 9 _! natural /ate !y are n g5]ally available = imm$iate use4 ,moreov]1 v _m sub/ances n[ deem$ indisp5sable are n f\nd ready =m$ 9 ,nature4 ,! end product ( ! *emical manufactur] is (t5 "o ( ! prim>y mat]ials ( "s o!r indu/ry4 ,soda a% & ,glaub]'s salt are ess5tial = mak+ glass2 soap c\ld n be produc$ )\t cau/ic alkali2 ! textile trade w\ld be s]i\sly h&icapp$ if blea*+ mat]ials1 mordants1 & dye-/uffs 7 n =?com+4 ,consid]$ 9 ?is light1 ! prep>ation ( *emicals is spok5 ( z a 8key indu/ry40 ,fur!rmore1 v few ( ^! indisp5sable sub/ances c be made )\t us+ sulphuric acid4 ,?is acid is1 on t acc\nt1 j z important to *emical indu/ries z ! products ( ^! are to o!r bran*es ( trade4 ,x may1 !re=e1 be look$ ^u z a ma/] key ( indu/rial life4 ,prim>y ,mat]ials4 ,! composition ( sulphuric acid is n difficult to und]/&4 ,air is ma9ly a mixture ( oxyg5 & nitrog52 & :5 a combu/ible body burns1 x is because *emical action betwe5 ! mat]ial & oxyg5 is tak+ place4 ,9 ?is way1 sulphur burns to sulphur dioxide4 ,?is gas1 dissolv$ 9 wat]1 =ms sulphurous acid1 :i* *anges sl[ly to sulphuric acid by comb9ation ) m oxyg54 ,h5ce1 sulphur1 oxyg51 & wat] are ! prim>y mat]ials requir$ = mak+ sulphuric acid4 ,sulphur is ! famili> yell[ solid commonly kn[n z brim/one4 ,x is f\nd native 9 ! e>?1 & is fairly abundant 9 c]ta9 localities1 notably 9 ! neighb\rhood ( active & ext9ct volcanoes4 ,italy1 ,sicily1 ,japan1 ,icel&1 & p>ts ( ! ,unit$ ,/ates are ! pr9cipal sulphur-produc+ c\ntries4 ,?\gh v pl5tiful & consequ5tly *eap1 only a relatively small quantity ( sulphuric acid is made directly f native sulphur1 because at ! "t :5 ?is indu/ry 0 />t$ 9 ,engl&1 re/rictions 7 plac$ on ! export ( sulphur f ,sicily &1 consequ5tly1 ! plant :i* 0 !n e/abli%$ 0 adapt$ to ! use ( iron pyrites4 ,iron pyrites conta9s ab\t #ec p] c5t4 ( sulphur comb9$ ) #dg p] c5t4 ( iron1 & :5 ?is is burnt 9 a good draught1 ne>ly ! :ole ( ! sulphur burns to sulphur dioxide1 leav+ a residue ( oxide ( iron :i* c be us$ = mak+ ca/ iron ( a l[ grade4 ,iron pyrites is (t5 supplem5t$ by ! 8sp5t oxide0 f ! gas works4 ,crude coal gas conta9s sulphur comp\nds :i*1 if n remov$1 w\ld burn ) ! gas & =m sulphur dioxide4 ,! production ( ^! pung5t & suffocat+ fumes w\ld be a s\rce ( great annoyance1 & !re=e x is necess>y to remove ! sulphur comp\nds4 ,to d ?is1 ! gas is pass$ ?r\gh two purifi]s1 ! fir/ conta9+ slak$ lime & ! second f]ric oxide1 bo? 9 a slightly moi/ condition4 ,aft] be+ "s "t 9 use1 ! purify+ mat]ial loses its efficacy2 ! residue f ! lime purifi] is sold z 8gas lime10 b t f ! f]ric oxide purifi] is expos$ to ! air & s 8reviv$40 ,at l5g?1 h[ev]1 x becomes s *>g$ ) sulphur t x is ( no fur!r use = its orig9al "w4 ,x is !n pass$ on to ! sulphuric acid mak]4 ,evolution ( ! ,manufactur+ ,process4 ,9 deal+ ) ! ma9 processes = ! manufacture ( acids & alkalis1 ref]5ce w frequ5tly be made to ! me?ods ( bygone times4 ,al?\gh z an exact sci5ce ,*emi/ry is comp>atively mod]n1 z a bran* ( human k its hi/ory goes back to ! dawn ( intellig5ce 9 man4 ,x is agre$ t ! high] types ( liv+ ?+s are m easily und]/ood :5 ^? ( a simpl] & m primitive "* h be5 /udi$4 ,9 l mann]1 ! highly specializ$ indu/ries ( mod]n times become m intelligible 9 ! light ( ! ef=ts ( pa/ g5]ations to a*ieve ! same object4 ,basil ,val5t9e1 :o liv$ 9 ! fifte5? c5tury1 /ates t ! liquid :i* we n[ call sulphuric acid 0 9 8 day obta9$ by heat+ a mixture ( gre5 vitriol & pebbles4 ,until q rec5t times1 sulphuric acid ( a special grade 0 made by precisely ! same me?od1 except t ! pebbles 7 disp5s$ )4 ,9 pass+1 we may rem>k t ! common "n 8vitriol10 or 8oil ( vitriol10 is acc\nt$ = by ?is connection ) gre5 vitriol4 ,! second me?od1 quot$ by ,basil ,val5t9e1 consi/$ ( ! ignition ( a mixture ( saltpetre & sulphur 9 ! pres5ce ( wat]4 ,?is is actually ! mod]n lead *amb] process 9 embryo4 ,illu/ration3 ,fig4 #b4 ,,plan ,,( ,,sulphuric ,,acid ,,works ,ab\t ! middle ( ! eighte5? c5tury1 8,dr40 ,w>d took out a pat5t = ! manufacture ( sulphuric acid1 to be c>ri$ on at ,ri*mond 9 ,surrey4 ,he us$ l>ge glass bell j>s ( ab\t #dj-ej galls4 capacity1 9 :i* he plac$ a little wat] & a flat /one to support a r$-hot iron ladle4 ,a mixture ( saltpetre & sulphur 0 ?r[n into ! ladle & ! m\? ( ! vessel quickly clos$4 ,aft] ! vigor\s *emical action 0 ov]1 ! ladle 0 re-heat$ & ! process repeat$ until at la/ fairly conc5trat$ sulphuric acid 0 produc$4 ,! l>ge glass vessels us$ by ,w>d 7 co/ly & easily brok54 ,!y 7 soon replac$ by *amb]s ab\t #f ft4 squ>e1 made ( %eet lead1 b o!rwise ! process 0 j ! same4 ,! next advance consi/$ 9 mak+ ! process cont9u\s in/ead ( int]mitt5t4 ,an enorm\sly increas$ output 0 !reby r5d]$ possible1 & ! ma9 features ( ! mod]n process gradually develop$4 ,! ,lead ,*amb] ,process4 ,we c n[ consid] ! actual work+ ( ! lead *amb] process1 aid$ by ! diagrammatic plan ( ! works %[n 9 ,fig4 #b4 ,sulphur dioxide is produc$ 9 a r[ ( kilns 7,a-,a7 by burn+ iron pyrites 9 a c>efully regulat$ curr5t ( air4 ,! mixture ( gases :i* leaves ! pyrites burn]s conta9s sulphur dioxide1 excess ( oxyg51 & a v l>ge quantity ( nitrog54 ,to ?is is add$ ! vap\r ( nitric acid1 g5]at$ f sodium nitrate & conc5trat$ sulphuric acid conta9$ 9 ! 8nitre pots10 :i* are plac$ at ,b4 ,! mixture ( gases !n passes up ! ,glov] t[] 7,c7 & ?r\gh ! ?ree *amb]s 9 succession1 into ! fir/ two ( :i* /eam is also introduc$4 ,sulphuric acid is actually produc$ 9 ! *amb]s1 & collects on ! floors1 f :i* x is drawn (f f "t to "t4 ,! residual gas f ! la/ *amb] is pass$ up ! ,gay ,lussac t[] 7,d71 & aft] t is dis*>g$ into ! air by way ( ! tall *imney 7,j74 ,illu/ration3 ,fig4 #c4 ,,g5]al ,,view ,,( ,,sulphuric ,,acid ,,works ,! ,oxyg5 ,c>ri]4 ,we h se5 t sulphur dioxide1 oxyg51 & wat] are ! only sub/ances requir$ to produce sulphuric acid4 ,:y1 !n1 is ! nitric acid vap\r add$ to ! mixture8 ,z describ$ 9 a =m] p>agraph1 ! comb9+ ( ^! gases 0 repres5t$ z be+ a v simple op]ation4 ,s inde$ x is1 = x ev5 takes place spontane\sly4 ,yet1 z a comm]cial process1 x w\ld be q impracticable )\t ! nitric acid vap\r1 = al?\gh ! gases comb9e spontane\sly1 !y d s v sl[ly1 & x is ! nitric acid vap\r :i* accel]ates ! rate ( comb9ation4 ,x is n kn[n ) any degree ( c]ta9ty h[ ! nitric acid acts 9 br++ ab\t ?is rem>kable *ange4 ,x has be5 sugge/$ t r$uction to nitrog5 p]oxide fir/ takes place1 & t sulphur dioxide takes oxyg5 f ?is body1 r$uc+ x /ill fur!r to nitric oxide1 :i* at once comb9es ) ! free oxyg5 pres5t to =m nitrog5 p]oxide aga94 ,s ! cycle ( *anges goes on1 ! nitrog5 p]oxide play+ ! "p ( oxyg5 c>ri] to ! sulphur dioxide2 & s9ce x is cont9ually reg5]at$1 x rema9s at ! end mix$ ) ! residual gases4 ,recov]y ( ! ,nitrog5 ,p]oxide4 ,if ! gases f ! la/ *amb] pass$ directly into ! *imney %aft1 !re w\ld be a total loss ( ! oxides ( nitrog51 & ! consequ5ce ( ?is w\ld be t m ?an #b cwt4 ( nitre w\ld h to be us$ = ! production ( #a ton ( sulphuric acid4 ,?is w\ld be a s]i\s item 9 ! co/ ( production1 & x is !re=e ess5tial t ?is loss %\ld be prev5t$4 ,! recov]y ( ! oxides ( nitrog5 is effect$ 9 ! ,gay ,lussac t[]1 a /ructure ab\t #ej ft4 9 height1 built ( %eet lead & l9$ ) acid-resi/+ brick4 ,x is fill$ ) fl9ts1 ov] :i* a sl[ /ream ( cold conc5trat$ sulphuric acid is deliv]$ f a tank at ! top4 ,z ! gas f ! la/ *amb] passes up ?is t[]1 x meets ! /ream ( acid com+ d[n4 ,?is dissolves & reta9s ! nitrog5 p]oxide4 ,! acid :i* collects at ! bottom ( ! t[] is kn[n z nitrat$ vitriol4 ,! next /ep is to br+ ! recov]$ nitrog5 p]oxide aga9 into circulation4 ,! nitrat$ vitriol is rais$ by compress$ air to ! top ( ! ,glov] t[]1 & z x trickles d[n ov] ! fl9ts 9 ?is t[] x is dilut$ ) wat]1 :ile at ! same "t x meets ! hot gases com+ f ! pyrites burn]s4 ,"u ^! conditions1 ! nitrog5 p]oxide is lib]at$ & c>ri$ along by ! curr5t ( gas into ! fir/ lead *amb]4 ,! /ream ( cold acid com+ d[n ! ,glov] t[] also s]ves to cool ! hot gases be=e !y ent] ! fir/ *amb]4 ,9 ord] to complete ! description ( ! works1 x is necess>y to add a note on ! lead *amb]s !mselves4 ,! %eet lead us$ 9 _! con/ruction is ( a v sub/antial "*2 x weighs ab\t #g lb4 p] squ>e foot4 ,! sep>ate /rips are jo9$ toge!r by autog5\s sold]+1 t is1 by fus+ ! edges toge!r4 ,9 ?is way ! pres5ce ( ano!r metal is avoid$2 o!rwise ?is w\ld =m a voltaic c\ple ) ! lead1 & rapid corrosion w\ld take place4 ,! size ( ! *amb]s has v>i$ a great deal4 ,9 ! e>ly ye>s ( ! n9ete5? c5tury1 ! capacity ( a s+le *amb] 0 probably n m ?an #a1jjj cu4 ft42 at ! pres5t "t1 #ch1jjj cu4 ft4 is an av]age size1 & !re may be ?ree or five ( ^! *amb]s4 ,! necessity = ?is l>ge am\nt ( cubic space is easily acc\nt$ =4 ,! reaction mat]ials are all gases1 & a gas occupies m ?an "o ?\s& times z mu* space z an equal weight ( a solid or liquid4 ,moreov]1 oxyg5 con/itutes only ab\t "o-fif? ( ! total volume ( air us$ 9 burn+ ! pyrites2 ! o!r f\r-fif?s is ma9ly nitrog51 :i*1 ?\gh x does n ent] into ! reaction at all1 has to pass ?r\gh ! *amb]s4 ,mod]n ,improvem5ts4 ,among ! mod]n innovations 9 ! lead *amb] process1 ! foll[+ are wor?y ( note4 8,atomiz$ wat]10 t is1 wat] "u high pressure deliv]$ f a f9e jet aga9/ a metal plate1 has c]ta9 advantages ov] /eam4 ,9 ord] to br+ ab\t a m rapid mix+ ( ! gases 9 ! *amb]1 x is propos$ to make ^! circul> in/ead ( rectangul>1 & to deliv] ! gases tang5tially to ! sides4 ,ano!r sugge/ion is to replace ! lead *amb]s by t[]s conta9+ p]=at$ /onew>e plates set horizontally4 ,by ?is arrangem5t1 s9ce ! holes are n plac$ opposite "o ano!r1 ! gases pass+ up ! t[] mu/ take a zig-zag c\rse4 ,?is makes = m effici5t mix+4 ,,! ,,contact ,,process ,sulphur ,trioxide4 ,:5 elem5ts are comb9$ 9 diff]5t proportions by weight1 !y produce diff]5t comp\nds4 ,?us1 9 ! case ( sulphur & oxyg51 !re are two well-kn[n comp\nds1 namely1 sulphur dioxide & sulphur trioxide4 ,9 ! =m]1 a giv5 weight ( oxyg5 is comb9$ ) an equal weight ( sulphur2 9 ! latt]1 ?is same weight ( sulphur is comb9$ ) #ej p] c5t4 m oxyg54 ,on ?is acc\nt1 sulphur trioxide is spok5 ( z ! high] oxide4 ,we c n[ /ate 9 g5]al t]ms ano!r me?od by :i* sulphuric acid c be built up f its elem5ts4 ,sulphur1 z we h se51 burns 9 oxyg51 =m+ sulphur dioxide4 ,?is sub/ance c !n be made to unite ) m oxyg5 to give sulphur trioxide1 :i*1 ) wat]1 yields sulphuric acid4 ,!re are ?ree /eps 9 ?is syn!sis4 ,! fir/1 namely1 sulphur to sulphur dioxide1 has already be5 consid]$2 ! la/1 sulphur trioxide to sulphuric acid1 only requires t sulphur trioxide & wat] %all be br\ght toge!r3 we c1 !re=e1 conf9e our att5tion to ! int]m$iate /ep1 namely1 ! conv]sion ( sulphur dioxide into trioxide4 ,?is op]ation1 :5 c>ri$ out 9 a *emical laboratory1 is a v simple "o4 ,fig4 #d %[s ! necess>y app>atus4 ,sulphur dioxide f a siphon ( ! liquefi$ gas & air f a ga%old] are pass$ into ! ,w\lff's bottle ,a1 conta9+ conc5trat$ sulphuric acid2 ?is removes moi/ure f ! gases4 ,! dry+ process is complet$ 9 ! t[] ,b1 :i* conta9s pumice /one soak$ 9 sulphuric acid4 ,! mix$ gases !n pass ?r\gh ! tube ,c1 conta9+ plat9iz$ asbe/os heat$ to ab\t #djj ,c43 ! sulphur trioxide collects 9 ! cool$ receiv] ,d4 ,illu/ration3 ,fig4 #d4 ,,sulphur ,,trioxide--,,! ,,contact ,,process ,plat9iz$ asbe/os is made by soak+ long-fibr$ asbe/os 9 a solution ( plat9um *loride4 ,! mat]ial is !n dri$ & subject$ to a g5tle heat4 ,9 ?is way1 metallic plat9um 9 an exce$+ly f9e /ate ( subdivision is deposit$ on ! asbe/os fibre1 :i* m]ely s]ves z a conv5i5t support4 ,catalytic or ,contact ,action4 ,! influ5ce ( ! f9ely divid$ plat9um is a v important factor 9 ! reaction4 ,x _c1 h[ev]1 be said to cause ! union ( sulphur dioxide ) oxyg51 = ! gases comb9e to a v slight ext5t :5 x is n pres5t4 ,:at ! plat9um actually does is to influ5ce ! rate ( =mation to su* a degree t1 "u fav\rable conditions1 practically ! :ole ( ! sulphur dioxide is *ang$ to sulphur trioxide in/ead ( an exce$+ly small fraction ( x4 ,! mo/ int]e/+1 & at ! same "t ! mo/ p]plex+1 feature ( ! reaction is t ! plat9um itself does n appe> to und]go any *ange4 ,x is n dim9i%$ 9 quantity1 = only a v small am\nt is necess>y = ! conv]sion ( a v l>ge am\nt ( ! mix$ gases4 ,its activity la/s = a v long "t1 & ev5 :5 x does become inactive1 x c be %[n t ?is is due to "s ext]nal cause1 su* z ! pres5ce ( du/ & c]ta9 impurities 9 ! gases4 ,_m o!r simil> cases are kn[n 9 :i* ! pres5ce ( a small quantity ( a ?ird sub/ance greatly influ5ces ! c\rse ( a *emical reaction )\t appe>+ 9 any o!r way to be necess>y to ! reaction4 ,^! sub/ances1 :i* are (t5 metals 9 a v f9e /ate ( subdivision1 are call$ catalytic or contact ag5ts4 ,! ,contact ,process = mak+ sulphuric acid is no?+ m nor less ?an ! simple laboratory op]ation :i* we h describ$ above1 c>ri$ out on a l>g] scale4 ,! sulphur dioxide is produc$ z 9 ! lead *amb] process by roa/+ iron pyrites 9 a curr5t ( air4 ,?is gas1 toge!r ) ! excess ( air1 is pass$ into ! contact furnace1 :i* consi/s ( f\r tubes1 ea* conta9+ plat9iz$ asbe/os1 support$ on p]=at$ plates4 ,! union ( ! two gases is said to be almo/ complete3 an effici5cy ( #ih p] c5t4 ( ! !oretical value is claim$ = ?is process4 ,! sulphur trioxide1 or 8sulphuric anhydride0#a is ei!r cond5s$ 9 t9-l9$ drums or absorb$ 9 ord9>y conc5trat$ sulphuric acid4 ,! proposal to manufacture sulphuric acid by ?is me?od 0 fir/ made 9 #ahca by ,p]egr9e ,phillips1 ( ,bri/ol4 ,! e>ly attempts 7 n successful1 & x 0 n until ab\t =ty-f\r ye>s lat] t ! difficulties aris+ 9 ! work+ ( ! contact process 7 ov]come suffici5tly to enable ! sulphuric acid produc$ 9 ?is way to be sold at ! same price z t made by ! lead *amb] process4 ,s9ce #ahij1 ! total quantity ( acid made by ! contact me?od has increas$ v rapidly1 s t x n[ furni%es ab\t "o-half ( ! _w's supply1 & seems likely 9 "t to displace ! lead *amb] process altoge!r4 ,! hi/ory ( ! rise ( ! contact process is int]e/+ because x illu/rates 9 a /rik+ mann] ! v great diff]5ce t !re is betwe5 a successful laboratory process & a successful manufactur+ process1 ?\gh seem+ly id5tical4 ,! fir/ & possibly ! mo/ s]i\s difficulty enc\nt]$ 9 ! work+ ( ! contact process 0 ! frequ5t int]ruption caus$ by ! loss ( activity ( ! contact sub/ance4 ,iron pyrites always conta9s ars5ic :i* volatilizes on heat+1 & ?is quickly caus$ ! plat9um to lose its activity1 or1 z x 0 sometimes r fancifully express$1 8poison$ ! cataly/40 ,du/ also is inevitable1 & ?is1 c>ri$ =w>d me*anically ) ! /ream ( gas1 settl$ on ! contact sub/ance & caus$ ! action to cease4 ,to get ov] ?is difficulty x is necess>y to purify ! gases4 ,!y are fir/ pass$ sl[ly ?r\gh *annels 9 :i* ! co>s] p>ticles ( du/ settle d[n4 ,/eam is inject$ into ! mixture to wa% out ! f9] p>ticles ( solid1 & also to get rid ( ars5ic1 & !n ! gases are pass$ ?r\gh scrubb]s4 ,be=e be+ admitt$ to ! contact furnace1 ! moi/ gas is submitt$ to an optical te/4 ,x is pass$ ?r\gh a tube1 ! ends ( :i* are transp>5t2 a bright light is plac$ at "o end & view$ f ! o!r ?r\gh a column ( gas ( consid]able l5g?4 ,if ! purification process is work+ satisfactorily1 !re is a complete abs5ce ( fog4 ,! gases are !n dri$ by pass+ ?r\gh conc5trat$ sulphuric acid & admitt$ to ! contact tubes4 ,9 all op]ations c>ri$ out on a l>ge scale1 ! regulation ( temp]ature is a matt] ( "s difficulty4 ,9 ! case :i* we are consid]+1 ! mo/ suitable temp]ature range is a r n>r[ "o1 & ! difficulty ( keep+ )9 ! limits is v mu* increas$ by ! l>ge am\nt ( heat giv5 out :5 ! sulphur dioxide & oxyg5 comb9e4 ,! result ( ! failure to ma9ta9 ! temp]ature at a fairly con/ant level 0 t ! process work$ 9 a v irregul> mann]1 = z soon z x 0 work+ really well & sulphur trioxide 0 be+ =m$ rapidly1 ! heat giv5 out by ! reaction itself 0 also great1 & consequ5tly1 ! high] temp]ature limit 0 exce$$4 ,! me?od ( controll+ ! temp]ature 9 ! contact process is wor? not+1 because x is really +5i\s4 ,! tubes conta9+ ! plat9iz$ asbe/os are surr\nd$ by wid] conc5tric tubes4 ,! gases :i* are ab\t to ent] ! contact furnace pass ?r\gh ! annul> space betwe5 ! two tubes1 & are !reby heat$ to ! requir$ temp]ature1 :ile at ! same "t !y s]ve to cool ! inn] tubes4 ,! mo/ satisfactory temp]ature is ab\t #djj ,c4 ,! tubes are fir/ w>m$ to #cjj ,c4 to />t ! reaction1 & !reaft] ! heat evolv$ by ! reaction itself is suffici5t to keep x go+4 ,! absorption ( ! sulphur trioxide also caus$ "s difficulty at fir/4 ,?is sub/ance reacts mo/ viol5tly ) wat]1 dissolv+ ) a hiss+ s\nd l t produc$ :5 a r$-hot pok] is plung$ into wat]4 ,at ! same "t great heat is develop$1 & consequ5tly1 mu* ( ! sulphur trioxide is vaporiz$1 & 9 t way lo/4 ,?is difficulty 0 got ov] by us+ #ih p] c5t4 sulphuric acid = ! absorption1 ! acid be+ kept at ?is /r5g? by ! simultane\s addition ( wat]4 ,! contact process has "s v di/9ct advantages ov] ! old] lead *amb] process4 ,! plant cov]s a mu* small] area ?an ! bulky lead *amb]s4 ,al?\gh ! prelim9>y purification ( ! gases is some:at t$i\s & co/ly1 ?is is 9 great measure comp5sat$ by ! purity ( ! acid produc$4 ,no sep>ate plant is requir$ = conc5tration & purification1 z 9 ! old] process4 ,f9ally1 sulphuric acid ( any conc5tration c be produc$ at w1 includ+ ! fum+ acid1 :i* is requir$ z a solv5t = indigo1 & 9 ! manufacture ( artificial indigo & o!r organic *emicals4 ,! lead *amb] process produces :at is call$ *amb] sulphuric acid v *eaply4 ,al?\gh ?is is only a #fj-gj p] c5t4 solution & v impure1 nev]!less1 x is q good en\gh = ! heavy *emical trade1 p>ticul>ly = ! fir/ /age ( ! ,leblanc soda process1 & = mak+ sup]phosphate4 ,^! two indu/ries alone consume _m ?\s&s ( tons ( ?is sulphuric acid e ye>4 ,probably = "s ye>s to come ! two processes w cont9ue to exi/ side by side1 b x may be d\bt$ :e!r new works w n[ be in/all$ to make sulphuric acid by ! lead *amb] process4 ,prop]ties ( ,sulphuric ,acid4 ,! pure non-fum+ acid is a col\rless oily liquid ^: d5sity is #ahd4 ,x mixes ) wat] 9 all proportions1 yield+ dilute sulphuric acid1 & x also dissolves sulphur trioxide1 yield+ ! fum+ acid4 ,! mix+ ( sulphuric acid & wat] is accompani$ by an evolution ( heat & by contraction 9 volume4 ,x is an op]ation :i* mu/ be c>ri$ out ) great c>e1 ! acid be+ always p\r$ into ! wat]1 o!rwise ! wat] floats on ! heavi] acid1 & s mu* heat is develop$ at ! surface ( sep>ation t "s ( ! wat] w be sudd5ly conv]t$ into /eam1 & ?is1 escap+ f ! liquid ) explosive viol5ce1 may cause ! cont5ts ( ! vessel to be scatt]$ ab\t4 ,/rong sulphuric acid *>s mo/ organic sub/ances4 ,f sub/ances su* z wood1 sug>1 pap]1 />*1 x )draws ! elem5ts ( wat]1 lib]at+ c>bon4 ,s9ce x acts 9 ! same way ^u human fle%1 x is cle> t ! conc5trat$ acid mu/ be h&l$ ) v great c>e1 = x causes mo/ pa9ful burns4 ,= ?is reason1 vitriol ?r[+ has always be5 reg>d$ z a mo/ s]i\s & da/>dly (f5ce4 ,a simple fir/-aid rem$y = burns produc$ by sulphuric acid is ! lib]al application ( an emulsion ( l9se$ oil & lime wat]4 ,! lime1 be+ an alkali1 neutralizes ! acid1 & ! oil excludes air f ! w\nd4 ,! read9ess ) :i* sulphuric acid comb9es ) wat] is (t5 made use ( bo? 9 ! laboratory & 9 indu/rial ,*emi/ry = ! purpose ( dry+ gases4 ,"o illu/ration ( ?is use has already be5 giv5 9 describ+ ! contact process4 ,ano!r in/ance :i* may be fairly famili> occurs 9 ! case ( liquefy+ air1 :]e ! gas mu/ be ?or\ghly dri$ be=e be+ pass$ into ! refrig]at+ app>atus1 o!rwise ?is w\ld soon become block$ ) ice4 ,! position :i* sulphuric acid occupies 9 ,*emi/ry is due ma9ly to ?ree out/&+ features4 ,9 ! fir/ place1 x is a /rong m9]al acid & displaces all o!r acids f _! salts4 ,secondly1 x has a high boil+ po9t 7#cch ,c471 & consequ5tly1 ! displac$ acid ) ! l[] boil+ po9t c be di/ill$ f ! mixture4 ,la/ly1 sulphuric acid c be made v *eaply f mat]ials :i* are v abundant 9 ,nature1 &1 !re=e1 x meets all ! requirem5ts ( an acid :i* is to be us$ = g5]al purposes4 ,,sulphates ,all ! common metals1 except gold & plat9um1 dissolve ei!r 9 conc5trat$ or 9 dilute sulphuric acid1 =m+ sulphates4 ,^! salts are highly important & int]e/+ sub/ances4 ,!y are all soluble 9 wat]1 ) ! exception ( ! sulphates ( calcium1 /rontium1 b>ium1 & lead4 ,f]r\s ,sulphate1 also call$ gre5 vitriol & copp]as1 is obta9$ by dissolv+ iron 9 dilute sulphuric acid4 ,! solution is gre51 & :5 x is evaporat$1 ! cry/als :i* sep>ate out look l bits ( gre5 glass4 ,x 0 because ( ?is t ! sub/ance 0 fir/ call$ gre5 vitriol 7vitrum glass74 ,x is us$ v l>gely 9 dye+ z a mordant4 ,writ+ ink & ,prussian blue are also made f x4 ,! ,alums are d\ble sulphates4 ,!y are made by cry/alliz+ solutions ( potassium1 sodium1 or ammonium sulphate toge!r ) solutions ( iron 7f]ric71 *romium1 or alum9ium sulphates4 ,9 ?is way1 we may h potassium alum9ium alum1 or iron ammonium alum1 & s on1 b :i*ev] comb9ation ( elem5ts is pres5t1 ! salt :i* is =m$ always cry/allizes 9 octah$ra4 ,! *ief use ( ! alums1 z also ( alum9ium sulphate1 is z mordants 9 dye+4 ,s9ce a great _m metallic salts1 p>ticul>ly acetates & sulphates1 are us$ 9 ! dye indu/ry z mordants1 x may be well to expla9 "h v briefly :at a mordant is4 ,x mu/ be rememb]$ t almo/ all ! dyes are solids :i* dissolve 9 wat]1 yield+ int5sely col\r$ solutions4 ,h5ce1 9 mo/ cases1 if a fabric is m]ely dipp$ 9 ! dye & !n dri$1 ! col\r+ is n p]man5t1 b c be wa%$ out ) wat]4 ,9 ord] to fix ! col\r+ matt]1 ! mat]ial is fir/ dipp$ 9 ! mordant1 usually a ba? ( "s metallic salt1 & !n1 g5]ally aft] exposure to air or aft] /eam+1 into ! dye ba?1 ) ! result t ! col\r becomes fix$4 ,! fir/ "p ( ! process is call$ 8mordant+0 ! mat]ial4 ,! mordant ei!r adh]es to or comb9es ) ! fibres1 & ! dye =ms ) ! mordant a col\r$ comp\nd call$ a 8lake10 :i* resi/s ! action ( wat]4 ,! col\r is !n said to be 8fa/10 t is1 firmly fix$4 ,= pr9t+ on calico1 ! mordant is ?ick5$ ) gum arabic or o!r glut9\s sub/ance4 ,! design is !n /amp$ on ! mat]ial ) ! ?ick5$ mordant liquor4 ,! subsequ5t treatm5t consi/s ( dipp+ ! mat]ial 9 ! dye & aft]w>ds 9 wat]1 :5 ! col\r comes away f ^? p>ts :i* h n receiv$ ! impress ( ! mordant4 ,sodium ,sulphate1 or ,glaub]'s salt1 is made f common salt by ! action ( conc5trat$ sulphuric acid4 ,x is "o ( ! raw mat]ials us$ 9 mak+ glass4 ,ammonium ,sulphate4 7,see p4 #ii47 ,calcium ,sulphate1 or gypsum1 occurs 9 l>ge quantities 9 ,nature4 ,! salt conta9s #bji p] c5t4 ( comb9$ wat]1 & :5 c>efully heat$ to #abj ,c1 x loses ab\t two-?irds ( ?is wat]1 yield+ a :ite p[d] kn[n z pla/] ( ,p>is4 ,?is sub/ance1 :5 made into a pa/e ) wat]1 gradually sets to a h>d mass1 because ! p>tially dehydrat$ gypsum re-comb9es ) ! wat]4 ,lead ,sulphate1 ! *ief impurity ( comm]cial oil ( vitriol1 is a :ite p[d] :i* is v (t5 us$ = mak+ :ite pa9t 9 place ( lead c>bonate 7:ite lead74 ,! sulphate has ! advantage ov] ! c>bonate 9 n be+ s readily discol\r$2 its disadvantage is t x lacks 8body40 ,copp] ,sulphate1 or blue vitriol1 is frequ5tly f\nd 9 ! dra9age ( copp] m9es1 :]e x is =m$ by ! oxidation ( copp] pyrites4 ,x is made on a l>ge scale by roa/+ sulphide ores ( copp] 9 a curr5t ( air4 ,oxyg5 comb9es ) copp] sulphide1 =m+ copp] sulphate1 :i* is extract$ ) wat] & cry/alliz$4 ,x =ms l>ge blue cry/als conta9+ #cf p] c5t4 ( wat]4 ,?is salt is put to _m diff]5t uses4 ,v l>ge quantities are us$ = dye+ & calico pr9t+2 "s ( ! gre5 pigm5ts1 su* z ,s*we9furt gre51 are made f x4 ,,*apt] ,,iii ,,nitric ,,acid ,,& ,,nitrates ,nitric acid1 ! aqua =tis ( ! al*emi/s1 mu/ be plac$ next to sulphuric acid 9 ! scale ( relative importance1 because ( ! v>iety ( its uses4 ,x is indisp5sable = mak+ explosives1 & is us$ = ! prep>ation ( drugs & f9e *emicals1 includ+ ! coal-t> dyes4 ,! acid also dissolves _m metals1 =m+ nitrates1 :i* are put to sev]al uses4 ,silv] nitrate is ! basis ( m>k+ ink1 & x is also ! sub/ance f :i* ! light-s5sitive silv] comp\nds requir$ = ! photographic indu/ry are made4 ,! important pigm5ts1 *rome yell[ & *rome r$1 are prep>$ f lead nitrate4 ,! solv5t action ( nitric acid on copp] is made use ( 9 et*+ designs on copp] plates4 ,ov] & above all ?is1 x mu/ be m5tion$ t an adequate supply ( 8nitrate0 is requir$ = artificial manure4 ,?us x c be said t ) ! uses ( ?is acid & its salts are associat$ our supply ( daily bread1 our fre$om f =eign oppression1 & _m ( ! ref9em5ts & conv5i5ces ( life4 ,we %all beg9 ! /udy ( nitric acid by tak+ /ock1 z x 71 ( ! natural s\rces ( supply4 ,! free acid is n f\nd 9 ,nature except = v small traces 9 ! air aft] ?und]/orms4 ,we h1 !re=e1 to rely entirely on t :i* c be obta9$ artificially4 ,until q rec5tly1 x c\ld be said t !re 0 only "o me?od ( mak+ ! acid1 namely1 by ! di/illation ( a mixture ( potassium or sodium nitrates & conc5trat$ sulphuric acid4 ,n[1 h[ev]1 nitric acid is be+ made f ! air1 ?\gh z yet only 9 small quantity1 not)/&+ ! great developm5t ( ?is me?od ow+ to w> requirem5ts2 h5ce1 we are /ill ma9ly dep5d5t on ! naturally occurr+ nitrates j m5tion$4 ,potassium ,nitrate 7nitre1 saltpetre1 sal prunella7 is f\nd 9 ! soil ( hot c\ntries1 especially 9 ! neighb\rhood ( t[ns & villages :]e ! sanit>y arrangem5ts are primitive4 ,9 v fav\rable circum/ances1 x may ev5 appe> z a :iti%1 mealy effloresc5ce on ! surface ( ! gr\nd4 ,to obta9 ! salt1 x is only necess>y to agitate ! surface soil ) wat] &1 aft] ! insoluble matt] has settl$ d[n1 to evaporate ! cle> solution4 ,potassium nitrate is requir$ = mak+ gunp[d]1 :i*1 until q rec5t times1 0 ! only explosive us$ 9 w>f>e4 ,cont95tal c\ntries t c\ld n af=d to rely entirely on sea-borne nitre _h to make _! own4 ,! refuse ( ! f>my>d1 mix$ ) lime & a%es1 0 made up into a heap ( loose texture1 :i* 0 p]iodically moi/5$ ) ! dra9age f ! /ables4 ,9 ! c\rse ( ye>s1 saltpetre & calcium nitrate 7 =m$ 9 ! surface lay]s1 f :i* !y 7 extract$ f "t to "t4 ,! f>m] 0 !n all[$ to pay "p ( 8 taxes 9 nitrates4 ,sodium ,nitrate1 also call$ cali*e1 ,*ili-saltpetre1 or ,*ili-nitrate1 comes ma9ly f ,s\? ,am]ica4 ,! b$s ext5d = a di/ance ( ab\t #bbj miles 9 ,*ili1 ,p]u1 & ,bolivia1 betwe5 ! ,&es m\nta9s & ! sea4 ,! deposit is ab\t #e ft4 ?ick1 & its av]age bread? #e miles4 ,! crude mat]ial is treat$ ) wat] 9 /eam-heat$ wood5 vats4 ,! cle> solution is evaporat$1 & ! residue obta9$ is wa%$ ) ! "m liquor & dri$4 ,?is product may conta9 z mu* z #ih p] c5t4 ( ! nitrate4 ,illu/ration3 ,fig4 #e4 ,,prep>ation ,,( ,,nitric ,,acid ,nitric ,acid4 ,*ili-nitrate is always us$ = mak+ nitric acid4 ,x is ! m abundant ( ! two naturally occurr+ nitrates1 & !re=e *eap]2 moreov]1 weight = weight1 x yields m nitric acid ?an ! correspond+ potassium comp\nd4 ,a mixture ( sodium nitrate & sulphuric acid is heat$ 9 a l>ge ca/-iron retort 7,c1 ,fig4 #e74 ,! retort is entirely surr\nd$ by flame & hot gases to prev5t ! cond5sation ( ! acid on ! upp] p>ts4 ,if ?is precaution 7 n tak51 ! acid w\ld dissolve ! iron & ! life ( ! retort w\ld n be long2 moreov]1 ! product w\ld conta9 f]ric nitrate z an impurity4 ,! vap\r ( ! acid is l$ away by ! tube ,d into a s]ies ( two-neck$ e>!nw>e receiv]s call$ bonbonnes 7,e71 & !re cond5ses to a liquid4 ,! l[] figure %[s h[ ! lead+ tube ( ! retort is protect$ f corrosion by ! clay tube a1 b2 & h[ x is connect$ to ! fir/ receiv] by ! glass tube e1 :i* is lut$ on at f4 ,! p]c5tage /r5g? ( ! acid :i* di/ils ov] dep5ds ^u t ( ! sulphuric acid us$ & on ! purity ( ! sodium nitrate4 ,pure nitric acid is a col\rless liquid #aeei times z heavy z wat]1 volume = volume4 ,x fumes /rongly 9 air1 & is a v corrosive liquid4 ,! pure acid ( comm]ce is obta9$ by di/illation ( a less conc5trat$ acid4 ,x is #fh p] c5t4 pure4 ,x is r5d]$ free f dissolv$ oxides ( nitrog5 by bl[+ air ?r\gh x4 ,:5 kept expos$ to light1 ! col\r *anges at fir/ to yell[ & !n to br[n1 because light causes a c]ta9 am\nt ( decomposition4 ,r$ fum+ nitric acid owes its col\r to ! great quantity ( oxides ( nitrog5 dissolv$ 9 x4 ,x is made by di/ill+ sodium nitrate t has be5 ?or\ghly dri$ ) ! /ronge/ sulphuric acid2 ! di/illation is c>ri$ out at a high temp]ature1 ) ! express purpose ( decompos+ "s ( ! nitric acid to furni% ! oxides ( nitrog54 ,sometimes a little p[d]$ />* is also add$ to facilitate ! =mation ( ^! oxides4 ,?is v>iety ( nitric acid is p>ticul>ly active & is us$ 9 _m op]ations1 especially 9 mak+ dyes1 explosives1 & o!r organic *emicals4 ,nitric acid has all ! g5]al prop]ties ( an acid1 t is1 x has a s\r ta/e ev5 9 v dilute solution1 x *anges ! col\r ( litmus to r$1 & dissolves c>bonates & _m metals4 ,:5 ! vap\r ( nitric acid is pass$ ?r\gh a r$-hot tube1 & also :5 a nitrate is /rongly heat$1 oxyg5 gas is giv5 (f4 ,analysis %[s t ! oxyg5 comb9$ 9 pure nitric acid am\nts to #gf p] c5t4 ( its weight1 :ile t 9 sodium & potassium nitrates is #ef & #ej p] c5t4 respectively4 ,nitric acid & ! nitrates are1 !re=e1 highly oxyg5at$ comp\nds2 moreov]1 "u fav\rable circum/ances1 !y are r easily brok5 up4 ,pure nitric acid w set fire to w>m1 dry sawdu/1 & a piece ( *>coal or sulphur ?r[n on ! surface ( molt5 nitre takes fire spontane\sly & is quickly consum$1 giv+ out a v vivid light4 ,! explanation ( ?is is t ! supply ( oxyg5 is abundant2 x is also readily available & conc5trat$ 9 a small space4 ,we c v>y ! exp]im5t4 ,:5 a mixture ( #ge p>ts by weight ( f9ely-p[d]$ saltpetre1 ) #ae ( *>coal du/ & #aj ( gr\nd sulphur1 is ignit$1 x burns v vigor\sly1 & is soon consum$4 ,?is mixture is1 inde$1 home-made gunp[d]4 ,explosives4 ,gunp[d] 0 discov]$ 9 v e>ly times by ! ,*9ese1 b = _m ye>s ! secret ( its composition did n get outside ! ,great ,wall4 ,9 ! fif? c5tury ,a4,d41 x 0 app>5tly re-discov]$ at ,con/ant9ople1 & t city 0 = a long "t def5d$ by ! use ( :at is kn[n 9 hi/ory z ,greek ,fire1 an inc5di>y mixture v simil> to1 if n actually ! same z1 gunp[d]4 ,b aga9 ! secret ( its composition 0 jeal\sly gu>d$1 & x 0 n until ! ?irte5? c5tury t x 0 discov]$1 app>5tly = ! ?ird "t1 & introduc$ to ,we/]n ,europe by ,rog] ,bacon4 ,x 0 us$ 9 siege cannon e>ly 9 ! f\rte5? c5tury & 9 field guns at ,crcy2 b x 0 app>5tly n employ$ = bla/+ until ab\t #afbg1 al?\gh 9 #afje1 ,guy ,fawkes & 8 fell[-conspirators 7 able to obta9 x 9 l>ge quantity4 ,f ! battle ( ,crcy 9 #acdf to ! beg9n+ ( ! ,s\? ,african campaign 9 #ahhi1 gunp[d] 0 ! only explosive us$ 9 w>f>e4 8,villa9\s saltpetre0 has !re=e play$ a v important "p 9 %ap+ ! c\rse ( ev5ts 9 ! _w's hi/ory4 ,at ! pres5t day1 gunp[d] has become 8old-fa%ion$40 ,9 w>f>e1 x has be5 sup]s$$ by 8smokeless0 p[d]s ( mu* great] p[]2 :ile = m9+ op]ations1 explosives ) a mu* great] %att]+ effect h long s9ce tak5 its place4 ,! composition ( gunp[d] may v>y1 b on ! av]age x conta9s #ge p>ts by weight ( saltpetre to #ae ( *>coal & #aj ( sulphur4 ,x is1 !re=e1 a mixture ( two combu/ible sub/ances1 ) a l>ge quantity ( a ?ird v ri* 9 oxyg54 ,! sep>ate con/itu5ts are v f9ely gr\nd & aft]w>ds ?or\ghly incorporat$4 ,:5 ! mixture is ignit$1 *>coal & sulphur burn v fi]cely 9 ! oxyg5 suppli$ by ! saltpetre4 ,! secret ( ! action ( gunp[d] lies 9 ! extraord9>y rapidity ) :i* combu/ion1 />t$ at "o po9t1 is propagat$ ?r\gh ! :ole mass4 ,moreov]1 ! products ( combu/ion are ma9ly gases1 & ^! occupy sev]al ?\s& times ! volume ( ! solid f :i* !y are produc$4 ,9 a conf9$ space1 a gas may ex]t enorm\s pressure :5 its normal t5d5cy to exp& is resi/$4 ,propellants4 ,al?\gh combu/ion is propagat$ ?r\gh a quantity ( gunp[d] ) v great rapidity1 x is n done in/antane\sly4 ,! "t requir$ is ab\t "o-hundr$? ( a second "u ord9>y conditions1 & ?is int]val1 %ort ?\gh x is1 is v important4 ,:5 ! object is to ?r[ a projectile1 ! in]tia ( ! latt] has to be ov]come1 t is1 a c]ta9 am\nt ( =ce has to be appli$ be=e ! heavy body beg9s to move4 ,9 ord] t ! /ra9 on ! bree* ( ! gun may be z small z possible1 ! pressure mu/ be gradually develop$ & mu/ rea* its maximum j z ! projectile beg9s to move4 ,! "t factor 9 ! explosion con/itutes ! diff]5ce betwe5 :at we n[ call 8propellants0 & 8high explosive40 ,propellants are explosives :i* develop pressure gradually1 & are !re=e us$ to laun* ! projectile2 high explosive develops pressure in/antane\sly1 & is !re=e us$ z ! bur/+ *>ge inside ! %ell1 bomb1 or torp$o1 & also 9 bla/+ op]ations4 ,cordite1 or smokeless p[d]1 is ! propellant n[ mo/ us$4 ,x is made by mac]at+ guncotton & nitroglyc]9e ) _! common solv5t acetone4 ,a pulp is ?us made to :i* #e p] c5t4 ( vasel9e is add$4 ,! mixture is !n =c$ ?r\gh a die1 & 9 ?is way x is =m$ into ?reads or rods1 :i* h>d5 z ! acetone evaporates4 ,cordite produces no smoke1 because all ! products ( its combu/ion are invisible gases4 ,high ,explosive4 ,nitroglyc]9e & ,guncotton are bo? explosives ( ! in/antane\s k9d4 ,! =m] is made by =c+ glyc]9e1 "u pressure 9 a v f9e /ream1 into a mixture ( fum+ nitric & conc5trat$ sulphuric acids2 ! latt] by soak+ cotton-wool 9 a simil> mixture4 ,bo? products are wa%$ ) wat] until q free f acid1 & subsequ5tly dri$4 ,nitroglyc]9e is a col\rless oil ) a burn+ ta/e4 ,! oil itself is v dang]\s to h&le1 = x is liable to explode spontane\sly ev5 :5 ! utmo/ c>e has be5 tak5 9 its prep>ation4 ,a m]e spot on a filt] pap] explodes ) a deaf5+ report :5 g5tly hamm]$ on an anvil2 & "o drop1 :5 heat$ on a /\t iron plate1 bl[s a hole ?r\gh ! plate4 ,no use c\ld be made ( ?is sub/ance = _m ye>s aft] its discov]y because x 0 s liable to explode dur+ transportation2 n[1 h[ev]1 x is made saf] by mix+ ) absorb5t infusorial e>? or kieselguhr4 ,?is mixture is kn[n z dynamite4 ,bla/+ gelat9e1 l cordite1 is a mixture ( nitroglyc]9e & guncotton4 ,tr9itrotolu5e 7,t4,n4,t47 is made f tolu5e & nitric acid1 & is a type ( ! mod]n high explosive4 ,x is a yell[ cry/all9e sub/ance :i* melts at #gi-hae ,c41 & is p\r$ into ! %ell 9 a molt5 condition4 ,x is a rem>kably /able sub/ance1 :i* burns quickly :5 heat$ to #ahj ,c42 x _c be explod$ ev5 by hamm]+4 ,explosion is only br\ght ab\t by t ( a subsidi>y sub/ance call$ ! detonator4 ,! p]c5tage composition ( ,t4,n4,t4 is z foll[s-- ,c>bon #cce ,hydrog5 #bc ,nitrog5 #aie ,oxyg5 #ddg #ajjj ,! oxyg5 pres5t is only j suffici5t to burn ! :ole ( ! c>bon to c>bon monoxide2 b s9ce c>bon dioxide is also =m$1 :i* requires twice z mu* oxyg5 = ! same weight ( c>bon1 & s9ce ! hydrog5 & nitrog5 may also be oxidiz$1 ! combu/ion ( ! c>bon is n complete2 & !re=e ! explosion ( ,t4,n4,t4 is accompani$ by a d5se black smoke1 consi/+ ( f9ely divid$ p>ticles ( c>bon4 ,! explosive kn[n z ammonal is a mixture ( ,t4,n4,t41 alum9ium p[d]1 & ammonium nitrate2 ! function ( ! latt] sub/ance is to supply m oxyg5 to r5d] ! combu/ion ( ! c>bon ( ,t4,n4,t4 complete4 ,nitrates & ! ,food ,supply4 ,*emical analysis %[s t comp\nds ( nitrog5 ent] l>gely into ! composition ( ! liv+ tissues ( all plants & animals2 h5ce1 ei!r nitrog5 itself or "s ( its comp\nds mu/ be assimilat$ by all liv+ organisms to provide = gr[? & developm5t1 & to repair wa/age4 ,air1 s9ce x conta9s approximately f\r-fif?s ( its volume ( free nitrog51 is ! mo/ obvi\s s\rce ( supply4 ,at e brea?1 a mixture ( oxyg5 & nitrog5 is inhal$ by animals1 b only "p ( ! oxyg5 is us$4 ,practically ! :ole ( ! nitrog5 is return$ to ! atmosph]e un*ang$2 x s]ves only to dilute ! oxyg54 ,f ?is x is cle> t animals d n build up _! nitrog5\s con/itu5ts f elem5t>y nitrog54 ,) plants x is v mu* ! same1 =1 al?\gh !y obta9 _! pr9cipal food1 namely1 c>bon1 f ! c>bon dioxide :i* is pres5t 9 air1 x is only 9 a few exceptional cases t free nitrog5 is assimilat$4 ,! exceptions w be consid]$ fir/1 because x 0 ?r\gh ^! t we fir/ began to le>n some?+ def9ite ab\t ! great importance ( nitrog5 9 agriculture4 ,virgil1 :o 0 born 9 #gj ,b4,c41 wrote a poem 9 praise ( agriculture4 ,almo/ 9 ! op5+ l9es he deals ) ! treatm5t ( corn l&4 ,he advises t1 9 alt]nate ye>s1 ?is %\ld ei!r be left fall[ or s[n ) pulse1 vet*1 or lup92 b n ) flax or oats1 because !y exhau/ ! l&4 ,f ?is we le>n t rotation ( crops 0 "o ( ! e/abli%$ pr9ciples ( good husb&ry ev5 at ! beg9n+ ( ! ,*ri/ian era4 ,x 0 n until ! lat] ye>s ( ! n9ete5? c5tury t any explanation z to :y rotation ( crops is b5eficial 0 put =w>d4 ,let u fir/ /ate ! facts m precisely4 ,peas1 beans1 vet*es1 clov]1 & o!r memb]s ( ! natural ord] call$ ,legum9osae1 :i* includes ab\t #g1jjj species1 produce fruits ri* 9 complex nitrog5 comp\nds )\t be+ dep5d5t 9 any way ^u nitrog5 comp\nds 9 ! soil4 ,moreov]1 !y d n exhau/ ! l& z f> z ^! comp\nds are conc]n$2 h5ce :eat & o!r gra9 c be gr[n on ! same l& ! foll[+ ye>4 ,x is n[ kn[n t legum9\s plants assimilate atmosph]ic nitrog5 ) ! help ( c]ta9 bact]ia4 ,if anyone w dig up a lup9 root1 he w obs]ve#b conspicu\s wr9kl$ swell+s or nodules at v>i\s po9ts on ! roots4 ,^!1 :5 exam9$ ) a high-p[] microscope1 are f\nd to conta9 colonies ( bact]ia4 ,x is ^! m9ute vegetable organisms :i* assimilate nitrog5 & pass on nitrog5 comp\nds to ! l>g] plant4 ,o!r plants _c assimilate :at we might call raw nitrog52 !y require soluble nitrates4 ,^! !y build up into complex organic nitrog5 comp\nds suitable = ! fe$+ ( animals :i* c assimilate nei!r free nitrog5 nor nitrates4 ,! ,nitrog5 ,cycle4 ,! supply ( nitrates 9 ! soil ne$s cont9ually to be r5ew$ by ! addition ( decay+ vegetable matt]1 /able or f>my>d manure1 or ,*ili saltpetre4 ,! natural manures conta9 organic nitrog5 comp\nds :i* 7 built up dur+ ! life ( "s animal or plant4 ,!y are n imm$iately available z food = o!r plants1 because !y are1 z x 71 ! end products ( life1 & are n soluble 9 wat]4 ,b ,nature provides = ?is4 ,! manures decay1 =m+ humus1 & ultimately ammonia1 "o ( ! simple/ ( inorganic nitrog5 comp\nds4 ,ammonia is !n trans=m$ to nitrites by c]ta9 bact]ia pres5t 9 ! soil1 :ile o!r bact]ia *ange nitrites into nitrates4 ,bo? ( ^! organisms are q di/9ct f ! root nodule bact]ia ( ! ,legum9osae4 ,! nitrates pass into ! plant 9 solution1 & !n beg9s aga9 t wond]ful cycle ( *anges :i* we h describ$4 ,?is is p]haps made cle>] by ! foll[+ diagram4 ,illu/ration3 ,fig4 #f4 ,,! ,,nitrog5 ,,cycle ,x n[ rema9s to %[ :y artificial manures also are necess>y4 ,let u consid] :at happ5s to a piece ( gr\nd :i* is left uncultivat$4 ,al?\gh no?+ is tak5 f x 9 ! way ( a crop1 yet x v quickly det]iorates1 & ! soil becomes inf]tile ?r\gh ! loss ( nitrog5 comp\nds4 ,?is is expla9$ by ! fact t nitrates are soluble 9 wat]1 & s !y get wa%$ away f ! top soil4 ,9 addition to ?is1 ! nitrog5 :i* is return$ to ! l& =ms q an insignificant fraction ( t :i* is tak5 f x1 = we wa/e a great deal ( organic nitrog54 ,! diff]5ce on bo? ^! acc\nts has1 !re=e1 to be made up by ! addition ( artificial manures conta9+ soluble nitrates4 ,! natural supply ( nitrate is v limit$4 ,accord+ to a report ( ! ,*ilian ,gov]nm5t publi%$ 9 #aiji1 ! nitre b$s ( t c\ntry 7 expect$ to la/ = less ?an a c5tury at ! curr5t rate ( consumption4 ,:eat1 above all ?+s1 w n gr[ to p]fection on soil :i* is defici5t 9 nitrate4 ,9 #aijh1 ,sir ,william ,crookes call$ att5tion to ! difficulty :i* might be exp]i5c$ 9 ! ne> future 9 supply+ ! p ( ! _w ) bread4 ,/ati/ics %[$ t :eat 0 gr[n on #aei1jjj1jjj acres out ( a possible #bfj1jjj1jjj4 ,! av]age yield is #abg bu%els p] acre4 ,by #aica1 x is calculat$ t ! population ( ! _w w be #a1gdf1jjj1jjj2 & to supply ^! ) bread1 :eat w\ld h to be gr[n on #bfd1jjj1jjj acres1 t is1 #d1jjj1jjj acres beyond ! total available :eat l&4 ,! rem$y :i* ,sir ,william ,crookes sugge/$ 9 ord] to avoid fam9e 0 to raise ! av]age yield f #abg to #bj bu%els p] acre by ! application ( an additional #ab1jjj1jjj tons ( ,*ili saltpetre p] annum4 ,9 view ( ! possible exhau/ion ( ! supply ( ?is sub/ance1 ?is w\ld only mean a po/ponem5t ( ! evil day4 ,! position1 h[ev]1 is n[ modifi$ to a great ext5t because undevelop$ deposits ( sodium nitrate are kn[n to exi/ 9 ,upp] ,egypt1 & ! mak+ ( nitric acid f ! air1 :i* 9 #aijh 0 put =w>d z a sugge/ion1 is n[ an accompli%$ fact4 ,nitric ,acid f ,air4 ,! supply ( nitrog5 9 ! air is truly inexhau/ible2 x am\nts to ab\t #g tons = e squ>e y>d ( ! e>?'s surface1 :i* is ab\t #bjj1jjj1jjj squ>e miles4 ,x is q evid5t t any?+ man may d 9 ! way ( tak+ nitrog5 f ! air w make no p]ceptible diff]5ce to its composition4 ,e "t a fla% ( lightn+ passes betwe5 a cl\d & ! e>?1 oxyg5 & nitrog5 comb9e 9 ! pa? ( ! sp>k1 produc+ oxides ( nitrog54 ,^! dissolve 9 wat]1 & are wa%$ into ! e>? z a v dilute solution ( nitric acid4 ,z long ago z #aghe1 ,h4 ,cav5di% imitat$ ?is natural ph5om5on4 ,a ref]5ce to ! diagram 7,fig4 #g7 w %[ h[ nitric acid c be made f ! air on a small scale4 ,! globe conta9s air "u slightly increas$ pressure4 ,! plat9um wires or c>bon rods are connect$ ) ! t]m9als ( an induction coil1 :i* 9 its turn is connect$ to accumulators supply+ ! curr5t requir$4 ,:5 ! coil is put into action1 a sp>k passes across ! gap betwe5 ! ends ( ! c>bon rods4 ,) a l>g] coil & a m p[]ful batt]y1 !re is an ar*+ flame :i* c be bl[n out & re-light$4 ,?is is actually nitrog5 burn+ 9 oxyg54 ,! result 9 ei!r case is ! same2 ! air 9 ! globe soon] or lat] acquires a r$di%-br[n col\r due to oxides ( nitrog51 :i*1 :5 %ak5 ) wat]1 =m a v dilute solution ( nitric acid4 ,! same process is n[ c>ri$ out on a l>ge scale4 ,air is driv5 by fans ?r\gh a v p[]ful electric arc1 :]eby #ae to #b p] c5t4 is conv]t$ into nitric oxide4 ,?is comb9es spontane\sly ) m oxyg5 to =m nitrog5 p]oxide1 :i*1 :5 dissolv$ 9 wat]1 gives a v dilute solution ( nitr\s & nitric acids4 ,illu/ration3 ,fig4 #g4 ,,nitric ,,acid ,,f ,,air ,! absorption ( ! oxides ( nitrog5 is c>ri$ out sy/ematically4 ,! mix$ gases1 aft] pass+ ?r\gh ! arc1 are pass$ ?r\gh a s]ies ( t[]s fill$ ) acid-resi/+ mat]ial ov] :i* a /ream ( wat] is fl[+4 ,! solution ( nitric acid s obta9$ is v dilute1 b by us+ ! liquid ov] & ov] aga91 a mod]ately /rong solution is ultimately produc$4 ,?is is collect$ 9 granite tanks & neutraliz$ ) lime1 =m+ calcium nitrate or ,norwegian saltpetre1 z x is n[ call$4 ,?is is a new indu/ry & a rapidly-gr[+ "o2 9 ! c\rse ( five ye>s 7#aije-aiji7 ! annual output ( ,norwegian or 8air0 saltpetre increas$ f #aae to #i1dbb tons4 ,m\nta9\s c\ntries l ,norway & ,switz]l& are p]haps 9 a specially fav\r$ position ) respect to ?is indu/ry4 ,rapid /reams & wat]falls1 9 conjunction ) turb9es1 are us$ = driv+ ! dynamos1 & 9 ?is way electricity is produc$ at v l[ co/4 ,x is int]e/+1 h[ev]1 to note t a plant = ! manufacture ( nitric acid f air has n[ be5 e/abli%$ 9 ,man*e/]4 ,,*apt] ,,iv ,,! ,,halog5 ,,acids ,a gr\p ( acids1 namely1 hydro*loric1 hydr(luoric1 hydrobromic1 hydriodic1 mu/ n[ be consid]$ toge!r ) _! correspond+ salts4 ,9 appe>ance & 9 o!r physical prop]ties !y resemble "o ano!r v closely2 !y are1 !re=e1 call$ by ! g5]al "n 8halog5 acids40 ,?is "n is d]iv$ f ! ,greek ^w mean+ 8sea-salt10 :i* is a mixture ( ! salts ( ^! acids1 & f :i* ! acids !mselves c be obta9$ by treatm5t ) oil ( vitriol4 ,hydro*loric ,acid4 ,:5 conc5trat$ sulphuric acid is add$ to common salt1 a gas is lib]at$ :i* has a v pung5t acid smell & ta/e4 ,?is is a comp\nd ( ! elem5ts hydrog5 & *lor9e1 & !re=e call$ hydrog5 *loride4 ,x is extremely soluble 9 wat]2 a giv5 volume ( wat] dissolves z mu* z #ejj times its own volume ( ! gas4 ,! solution produc$ 9 ?is way is n[ call$ hydro*loric acid1 b =m]ly x 0 kn[n z spirits ( salt1 or muriatic acid4 ,hydro*loric acid has all ! g5]al prop]ties ( acids4 ,x dissolves _m metals1 su* z z9c1 iron1 alum9ium1 & magnesium2 hydrog5 gas is giv5 (f1 & ! *loride ( ! metal is =m$4 ,x also dissolves lime/one1 m>ble1 & all =ms ( calcium c>bonate2 c>bon dioxide gas is lib]at$1 & a solution ( calcium *loride rema9s4 ,! hydro*loric acid ( comm]ce is obta9$ z a by-product 9 ! manufacture ( wa%+ soda f common salt by ! me?od propos$ by ,ni*olas ,leblanc t[>ds ! end ( ! eighte5? c5tury4 ,9 ! fir/ /age ( ?is process1 salt is mix$ ) sulphuric acid2 ?is causes ! lib]ation ( hydrog5 *loride gas1 :i*1 :5 dissolv$ 9 wat]1 produces hydro*loric acid4 ,! pa/ hi/ory ( ?is bran* ( *emical indu/ry is int]e/+4 ,until ab\t #ahgj1 !re 0 no v great dem& = hydro*loric acid1 & 9 ! e>ly days ( ! work+ ( ! ,leblanc process ! soda manufactur] took no pa9s to recov] m ?an he c\ld actually sell4 ,consequ5tly1 a l>ge quantity ( hydrog5 *loride gas 0 all[$ to escape into ! air1 ) results :i* c well be imag9$4 ,= miles ar\nd1 great damage 0 frequ5tly su/a9$ by ! gr[+ crops2 :5 x ra9$ 9 ! neighb\rhood ( ! works1 ! gas 0 wa%$ out ( ! air &1 speak+ q lit]ally1 x ra9$ dilute hydro*loric acid1 :i* rapidly corrod$ all /one & metal "w4 ,x is n1 !re=e1 surpris+ to le>n t alkali mak]s 7 frequ5tly involv$ 9 litigation1 & *emical works 7 reg>d$ z a great nuisance4 ,by ! ,alkali ,act ( #ahfc1 *emical manufactur]s 7 compell$ to prev5t ! escape ( m ?an #e p] c5t4 ( hydro*loric acid gas2 & by a subsequ5t ,act1 ?is limit 0 l[]$ to #jb gra9 p] cubic foot4 ,! provisions ( ! ,acts 7 n difficult to c>ry out1 because hydrog5 *loride is extremely soluble 9 wat]4 ,! gases com+ f ! pans 9 :i* ! salt 0 decompos$ 7 l$ into t[]s 7see ,fig4 #h7 built ( bricks or ,york%ire flags soak$ 9 t>4 ,^! t[]s 7 fill$ up ) coke or o!r acid-resi/+ mat]ial1 :i* 0 kept moi/ by wat] fl[+ f ! tank ,f4 ,9 ?is way1 hydrog5 *loride gas 0 remov$ & hydro*loric acid collect$ 9 tanks 7n %[n 9 ! figure7 at ! bottom ( ! t[]s4 ,ev5 !n1 !re 0 no m>ket = ! great] "p ( ! recov]$ acid1 consequ5tly mu* ( x f\nd its way into dra9s & /reams1 & s c>ri$ on its "w ( de/ruction 9 a less obtrusive way4 ,illu/ration3 ,fig4 #h4 ,,prep>ation ,,( ,,hydro*loric ,,acid ,by ano!r piece ( legislation1 :i* at fir/ sight seems to be :olly unconnect$ ) ,*emi/ry1 hydro*loric acid acquir$ a greatly enhanc$ value4 ,9 #ahfa1 ! tax on pap] 0 remov$1 & 9 ! next tw5ty ye>s ! dem& = t commodity increas$ s mu* t raw mat]ial bo? *eap] & m abundant ?an rag _h to be f\nd4 ,esp>to grass & ev5tually wood pulp prov$ successful sub/itutes4 ,!re is really v little diff]5ce 9 composition betwe5 cotton & l95 rag on ! "o h& & wood fibre on ! o!r1 = bo? are ma9ly compos$ ( cellulose1 :i* is a def9ite *emical comp\nd4 ,wood fibre is ! less pure1 & x is also col\r$1 & !re=e has to be blea*$ be=e x c be us$ = mak+ :ite pap]4 ,x 0 ?is circum/ance :i* l$ to ! greatly increas$ dem& = hydro*loric acid4 ,at ! beg9n+ ( ?is *apt]1 x 0 m5tion$1 9 pass+1 t hydrog5 *loride gas is a comp\nd ( hydrog5 & *lor9e4 ,! latt] elem5t is a v active blea*+ ag5t1 & is mo/ easily obta9$ by treat+ hydrog5 *loride or its solution 9 wat] ) pyrolusite 7black oxide ( manganese71 :]eby ! hydrog5 is oxidiz$1 =m+ wat]1 & *lor9e gas is set free4 ,be+ a gas1 *lor9e is n conv5i5t to h&le 9 l>ge quantities2 x is1 !re=e1 conv]t$ into blea*+ p[d]1 commonly b wrongly call$ *loride ( lime4 ,blea*+ ,p[d]4 ,! manufacture ( blea*+ p[d] is c>ri$ out 9 ! foll[+ way4 ,slak$ lime to ! dep? ( #c or #d 94 is spread ov] ! floor ( a special *amb] :i* c be made gas-tight4 ,! lime is rak$ up into ridge & furr[1 & ! *amb] is fill$ ) *lor9e4 ,at ! end ( ab\t tw5ty-f\r h\rs1 ! great] "p ( ?is *lor9e w h be5 absorb$ by ! lime4 ,! *amb] is !n op5$1 ! lime is rak$ ov] to expose a fre% surface1 & ! process ( *lor9ation is repeat$4 ,g5]ally ?is is suffici5t2 ! blea*+ p[d] %\ld !n conta9 ab\t #ce p] c5t4 ( available *lor9e4 ,! dem& = blea*+ p[d] is great & /eadily increas+4 ,! price ( #ce p] c5t4 blea*+ p[d] has nev] be5 less ?an ab\t #e a ton1#c s t x is p]haps unnecess>y to add t ! absorption ( hydrog5 *loride gas is n[ made s complete t x is well )9 ! requirem5ts ( ! second ,alkali ,act4 ,*lorides4 ,! salts ( hydro*loric acid are call$ *lorides1 & ! mo/ important ( ^! is sodium *loride or common salt--a body t is s well kn[n t x ne$ n be describ$ "h4 ,al?\gh ! quantity ( ?is sub/ance requir$ = dome/ic purposes is v l>ge1 x is1 nev]!less1 small by comp>ison ) t :i* is us$ = indu/rial purposes4 ,x has already be5 m5tion$ t salt is ! />t+-po9t = ! manufacture ( wa%+ soda by ! ,leblanc process1 &1 9 addition to ?is1 x is employ$ 9 ! glass indu/ry to produce :it5ess & transp>5cy 9 c]ta9 k9ds ( glass2 9 pott]y1 = glaz+ e>!nw>e2 9 soap-mak+1 = salt+ out ! crude soap2 & 9 ! dye trade z a mordant1 & also = improv+ ! quality ( c]ta9 col\rs4 ,a full acc\nt ( ! salt indu/ry is giv5 9 ano!r volume ( ?is s]ies4 ,hydr(luoric ,acid4 ,:5 calcium fluoride 7fluorsp>1 ,d]by%ire sp>1 or blue-john7 is w>m$ ) conc5trat$ sulphuric acid 9 a lead5 di%1 hydrog5 fluoride gas is evolv$1 & ?is1 :5 dissolv$ 9 wat]1 gives hydr(luoric acid4 ,! peculi> prop]ty ( ?is sub/ance is t x has a v m>k$ corrosive action on glass4 ,x _c1 !re=e1 be kept 9 glass vessels1 b mu/ be /or$ 9 bottles made ( h>d5$ ca\t*\c4 ,on ! o!r h&1 x is ?is same prop]ty :i* gives x its place 9 comm]ce4 ,z f> back z #afgj x 0 us$ = et*+ on glass4 ,! process is a v simple "o4 ,! article is fir/ coat$ ) wax1 :i* is !n remov$ 9 places by a %>p po9t$ tool4 ,:5 expos$ to ! action ( ! gas or its solution1 corrosion takes place only :]e ! glass has be5 laid b>e1 ! o!r p>ts be+ protect$ by ! wax4 ,aft] a %ort int]val1 ! wax c be melt$ (f1 & ! design made m di/9ct by rubb+ 9 "s opaque cem5t4 ,= g5]al trade purposes1 su* z ! /amp+ ( lamp *imneys or electric light bulbs1 a quick] me?od is requir$4 ,9 ?is case1 a prep>ation ( hydr(luoric acid :i* c be appli$ ) a rubb] /amp is us$4 ,fluorsp> or calcium fluoride is ! mo/ important salt ( hydr(luoric acid4 ,x is a commonly occurr+ m9]al1 & besides its use = ! prep>ation ( ! acid1 x is employ$ 9 _m metallurgical op]ations to =m a fusible slag4 ,hydrobromic & ,hydriodic ,acids are n mu* us$1 b _! salts1 ! bromides & iodides respectively1 are ( great te*nical importance4 ,silv] *loride1 bromide1 & iodide1 are s5sitive to light1 & mix$ ) gelat9e !y =m ! emulsion :i* is spread ov] photographic plates & pap]s4 ,potassium bromide & iodide are also well kn[n to photograph]s4 ,:5 ! halog5 salts ( silv] are expos$ to light1 an extremely subtle *emical *ange takes place1 :i* is only made app>5t :5 ! plate or pap] is develop$4 ,!n ! silv] salts on :i* ! light has fall5 are r$uc$ to metallic silv]1 & ?is r$uction is greate/ :]e ! light 0 mo/ int5se1 & 9 o!r places is proportional to ! light int5sity4 ,a v fa9t image may appe> on ! plate :ile x is 9 ! develop]1 b g5]ally ! image is only br\ght out cle>ly :5 ! plate1 film1 or pap] is plac$ 9 8hypo0 solution1 :i* dissolves out ! silv] salts :i* h n be5 *ang$1 leav+ ! metallic silv] unaffect$4 ,,*apt] ,v ,,c>bonic ,,acid ,,& ,,c>bonates ,c>bon4 ,:5 any product ( animal or vegetable life is /rongly heat$ 9 a vessel f :i* all air curr5ts are exclud$1 a mixture ( gases & liquids is driv5 (f1 & a *>r$ mass rema9s4 ,?is residue1 f :atev] s\rce obta9$1 is compos$ ma9ly ( ! elem5t c>bon4 ,x sometimes happ5s t a loaf ( bread or a cake is left 9 ! ov5 & =gott54 ,9 popul> language x is !n said to be 8burnt to a c9d]02 9 reality1 ! surface lay]s h be5 conv]t$ into c>bon4 ,c>bonic ,acid4 ,if c>bon is heat$ 9 an op5 vessel provid$ ) a good draught1 x gl[s & 9 "t disappe>s1 because x comb9es ) oxyg5 to =m an invisible gas1 c>bon dioxide or c>bonic acid gas1 :i*1 :5 dissolv$ 9 wat]1 =ms c>bonic acid4 ,comp>$ ) ! acids :i* h be5 describ$ 9 ! =ego+ *apt]s1 ?is is a v feeble acid2 x *anges ! col\r ( litmus to a w9e r$1 n a bright p9k2 its ta/e is j pleasantly acid1 & its solv5t action on metals & lime/one is v small inde$4 ,! solution ( ! acid1 obta9$ by pass+ c>bon dioxide into wat]1 is1 ( c\rse1 v dilute1 & x _c be conc5trat$ by evaporation1 s9ce ?is only results 9 expell+ ! c>bon dioxide f solution1 leav+ pure wat]4 ,soda ,wat]4 ,9 ! case ( mo/ gases1 ! weight :i* dissolves 9 a giv5 quantity ( wat] is proportional to ! pressure4 ,?is is true = c>bonic acid gas4 ,"u a pressure ( #d atmosph]es1 ! weight ( gas :i* dissolves is f\r times z great z "u a pressure ( "o atmosph]e4 ,soda wat] is wat] *>g$ ) c>bon dioxide "u pressure4 ,?is pressure is ma9ta9$ f ! "t x leaves ! manufactur] to ! "t x rea*es ! consum] by ! /rong walls ( ! syphon or bottle4 ,imm$iately ?is pressure is releas$1 ! great] "p ( ! excess gas escapes1 produc+ eff]vesc5ce4 ,x is1 h[ev]1 curi\s to note t all ! gas :i* ought to escape :5 ! pressure is r$uc$ does n d s at once4 ,if soda wat] is all[$ to /& 9 an op5 glass until x becomes 8flat10 a brisk eff]vesc5ce c be />t$ aga9 by dropp+ a lump ( sug> into ! quiesc5t liquid4 ,soda wat] rema9s sup]saturat$ ) gas = "s "t aft] ! pressure has be5 releas$4 ,calcium ,c>bonate4 ,! salts ( c>bonic acid are call$ c>bonates4 ,calcium c>bonate is "o ( ! mo/ abundant sub/ances 9 ,nature4 ,! :ite cliffs ( ! ea/ & s\? coa/s ( ,engl&1 & ^? ( ,france across ! int]v5+ sea1 are ! expos$ p>ts ( enorm\s b$s ( *alk or calcium c>bonate4 ,:ole m\nta9 ranges 9 v>i\s p>ts ( ! _w are compos$ ( lime/one1 :i* 9 "s cases is ma9ly calcium c>bonate1 & 9 o!rs a mixture ( ?is sub/ance ) magnesium c>bonate4 ,m>ble1 :e!r :ite1 black1 or v>iegat$1 is almo/ pure calcium c>bonate1 ! diff]5ces ( col\r be+ due to insignificant traces ( iron & o!r =eign matt]4 ,9 ,icel& sp> & calc sp>1 sometimes call$ dog-too? sp>1 we h two transp>5t cry/all9e =ms ( ?is same sub/ance4 ,connect$ ) ! animal k+dom !re are =ms ( calcium c>bonate no less v>i$ 9 appe>ance4 ,egg %ells are compos$ ( ?is sub/ance1 & s are oy/] %ells & ! h>d ext]nal cov]+s ( "s ( ! l[] animals4 ,! "m-(-pe>l l9+ ( ! oy/] %ell1 & also ! pe>l itself1 are secretions ( calcium c>bonate4 ,! beauty ( ! la/-nam$ v>iety is due to ! ext]nal =m & to m9ute inequalities ( ! surface1 :i* cause ! resolution ( :ite light into col\rs se5 9 ! spectrum or 9 ! ra9b[4 ,! coral reefs or atolls ( ! ,s\!rn oceans1 :i* may be miles 9 bread? & hundr$s ( miles 9 l5g?1 are all compos$ ( calcium c>bonate1 :i* a t9y m>9e animal has =m$ = its own support & protection4 ,x is p]haps some:at surpris+ at fir/ to be told t all ^! =ms are compos$ ( ! same *emical sub/ance1 yet on ?is po9t ! evid5ce is def9ite & unmi/akable4 ,all ! v>ieties dissolve readily 9 dilute hydro*loric acid ) eff]vesc5ce caus$ by ! escape ( c>bon dioxide gas2 moreov]1 if any ( ! pur] =ms1 su* z pe>l1 m>ble1 or ,icel& sp>1 are heat$ to r$ness = "s "t1 !y all lose ab\t #dd p] c5t4 by weight1 leav+ a residue :i* is pure lime4 ,quicklime4 ,! mak+ ( lime f lime/one or *alk is call$ lime burn+4 ,! op]ation is c>ri$ out 9 a /ructure call$ a lime kiln1 :i* is usually a b>rel-%ap$ v]tical %aft surr\nd$ by sub/antial brickwork4 ,!re are two ma9 me?ods ( proc$ure1 ! "o cont9u\s & ! o!r int]mitt5t4 ,9 ! cont9u\s process1 ! kiln is fill$ up ) lime/one & fuel 7g5]ally coke7 9 alt]nate lay]s4 ,combu/ion is />t$ at ! bottom & ma9ta9$ by a regulat$ draught4 ,z ! *>ge works d[n1 ! addition ( lime/one & fuel is cont9u$ f ! top1 :ile ! lime is remov$ f ! bottom ( ! kiln4 ,! lime produc$ by ?is me?od has ! a%es ( ! fuel mix$ ) x4 ,to avoid ?is1 ! m mod]n type ( kiln has f\r lat]al fire grates outside ! actual kiln4 ,= ! int]mitt5t me?od1 a kiln is requir$ :i* has a fireplace at ! bottom4 ,ov] ?is a r\gh ar* is built ( l>ge pieces ( lime/one1 laid dry1 & !n ! kiln is fill$ up ) pieces ( lime/one :i* decrease 9 size f bel[ upw>ds4 ,! fire is k9dl$ b5ea? ! ar* & urg$ by a regulat$ draught4 ,! heat+ is ma9ta9$ = ?ree days & nights1 aft] :i* "t ! *>ge is all[$ to cool d[n4 ,c>bonic ,acid ,gas 9 ,nature4 ,al?\gh ! solv5t action ( c>bonic acid is v small comp>$ ) t ( /rong acids1 x is nev]!less great 9 comp>ison ) t ( wat]4 ,?is is %[n especially 9 its action on lime/one1 an action f :i* sev]al important consequ5ces arise4 ,ra91 z x falls ?r\gh ! air1 dissolves a little c>bon dioxide &1 al?\gh ?is is only an exce$+ly dilute solution ( a v weak acid1 its cumulative effect1 especially 9 lime/one di/ricts1 is v great2 x holl[s out enorm\s caves & causes ! =mation ( ^? fanta/ic creations 9 /one kn[n z /alactites & /alagmites4 ,:5 a drop ( wat] *>g$ ) c>bonic acid gas falls on lime/one1 x dissolves a little ( t sub/ance1 =m+ calcium bic>bonate1 :i* may be reg>d$ z a comp\nd ( calcium c>bonate1 c>bon dioxide1 & wat]4 ,little by little1 ! solid rock is holl[$ out & a cave1 or p]haps an und]gr\nd wat]c\rse1 is =m$4 ,aga91 ! drop ( wat] *>g$ ) calcium bic>bonate may f9d its way to ! ro( ( a cave4 ,z x hangs f ! ro( :ile x ga!rs /r5g? to fall1 a little ( ! c>bon dioxide escapes1 & a m9ute quantity ( calcium c>bonate is deposit$4 ,9 ?is way1 a /alactite look+ l an icicle 9 /one gradually gr[s d[nw>ds4 ,:5 ! drop rea*es ! floor ( ! cave1 a little "t elapses be=e x s9ks into ! gr\nd2 aga9 a little c>bon dioxide escapes1 & a small quantity ( calcium c>bonate is =m$4 ,little is add$ to little1 & 9 ! c\rse ( ages ! /alagmite gr[s upw>d f ! floor & ultimately meets ! /alactite to =m a cont9u\s column ( gli/5+ cry/alliz$ calcium c>bonate4 ,h>d & ,s(t ,wat]4 ,wat] t is us$ = dome/ic or manufactur+ purposes is describ$ z ei!r h>d or s(t4 ,s(t wat] produces a soap la!r almo/ at once2 h>d wat] =ms at fir/ a scum or curd :i* has no det]g5t prop]ties1 & only aft] a "t gives ! soap la!r :i* is requir$4 ,! diff]5ce is due to ! relative am\nt ( dissolv$ solid conta9$ 9 ! wat]4 ,only di/ill$ wat] or ra9 wat] collect$ 9 ! op5 c\ntry is p]fectly s(t1 = ?is is ! only k9d ( wat] :i* on be+ evaporat$ to dryness leaves no solid residue4 ,9 di/ricts :]e ! und]ly+ /rata are compos$ ( h>d insoluble rock1 su* z granite or mill/one grit1 ! wat] conta9s v little dissolv$ matt] & is relatively s(t4 ,9 a lime/one or *alk c\ntry1 wat] is v h>d & 9 _m cases has to be s(t5$ ei!r be=e deliv]y or be=e use4 ,! *ief impurities :i* cause h>dness are ! *lorides1 sulphates1 & bic>bonates ( magnesium & calcium4 ,! *lorides & sulphates are n affect$ 9 any way by boil+1 & ! h>dness :i* is due to !m is said to be 8p]man5t40 ,! bic>bonates1 on ! o!r h&1 are decompos$ :5 ! wat] is boil$1 & !n !y cease to cause ! wat] to be h>d4 ,?is "p ( ! h>dness is spok5 ( z 8tempor>y0 h>dness4 ,let u n[ consid] :at calcium bic>bonate is & h[ x is =m$4 ,x is a comp\nd ( calcium c>bonate & c>bonic acid1 & is =m$ by ! solv5t action ( c>bonic acid on lime/one or *alk4 ,! comp\nd is soluble 9 wat]2 b :5 ! solution is boil$1 ! c>bonic acid is brok5 up1 c>bonic acid gas is expell$ f ! solution1 & calcium c>bonate is =m$4 ,tempor>y h>dness is ! m tr\blesome4 ,9 ! fir/ place1 ! bic>bonates1 especially t ( calcium1 (t5 =m ! great] "p ( ! dissolv$ impurity4 ,moreov]1 :5 ! wat] is boil$1 al?\gh ! h>dness is remov$1 ! insoluble calcium c>bonate is a s\rce ( tr\ble1 = x gradually settles d[n into ! h>d mass kn[n z 8fur0 9 kettles & 8scale0 9 boil]s4 ,x is p]haps necess>y at ?is po9t to emphasize ! fact t matt] susp5d$ 9 wat] does n make x h>d1 & x is only matt] :i* is dissolv$ :i* makes any diff]5ce 9 ?is respect4 ,s9ce ! s(t5+ ( tempor>y h>d wat] by boil+ has ! undesirable feature ( introduc+ solid matt] into ! boil]1 x is cu/om>y n[ to treat ?is wat] *emically4 ,! foll[+ is ! process mo/ g5]ally us$4 ,quicklime or slak$ lime is /irr$ into ! wat] until ! mixture gives a fa9t br[n coloration :5 a drop ( silv] nitrate is add$ to a small te/ portion4 ,uns(t5$ wat] is !n add$ until a sample j ceases to give ?is te/4 ,! tempor>y h>dness has !n be5 remov$1 & x is only necess>y to all[ ! susp5d$ matt] to settle4 ,! explanation ( ! me?od is z foll[s4 ,! lime :i* is add$ neutralizes ! c>bonic acid comb9$ ) ! calcium bic>bonate1 & ! result is ! same z 9 ! =m] case :]e ?is c>bonic acid 0 decompos$ by heat+1 = calcium c>bonate is ?r[n out ( solution4 ,= dome/ic purposes1 wat] is s(t5$ by ! addition ( wa%+ soda4 ,s9ce ?is reacts ) all ! calcium & magnesium comp\nds =m+ ! insoluble c>bonates1 all h>dness1 bo? tempor>y & p]man5t1 is remov$4 ,,*apt] ,,vi ,,phosphoric1 ,,boric1 ,,& ,,silicic ,,acids ,! acids :i* are gr\p$ 9 ?is *apt] are n 9 !mselves ( mu* int]e/1 ?\gh "s ( _! salts are extremely important comp\nds4 ,bone4 ,mu* ( ! refuse bone1 soon] or lat]1 rea*es ! m>9e /ore1 & f t po9t />ts on a c>e] ( usefulness 9 ! indu/rial _w4 8,gre5 bone10 z x is !n call$1 may h fat adh]+ to x or conf9$ 9 its holl[ int]ior z m>r[4 ,?is is recov]$ by treatm5t ) b5z9e1 & aft] t ! bone is subject$ to ! action ( sup]heat$ /eam 9 ord] to conv]t c>tilage into glue4 ,9 "s cases1 ! residue is !n gr\nd up to make bone meal1 :i* is valuable z a manure because ( ! calcium phosphate :i* x conta9s4 ,9 ?is way1 ! phosphate returns aga9 to ! animal k+dom1 = x supplies plants ) ! phosphates t !y require1 & f ! vegetable k+dom x passes to animals & helps to build up bone aga94 ,calcium ,phosphate & ,bone ,black4 ,in/ead ( be+ gr\nd up1 bone may be heat$ 9 a retort 9 mu* ! same way z coal is treat$ = ! manufacture ( coal gas2 bone oil is di/ill$ (f1 & a non-volatile residue1 call$ bone black or animal *>coal1 rema9s4 ,?is conta9s ab\t #ij p] c5t4 ( calcium phosphate & #aj p] c5t4 ( f9ely divid$ c>bon dissem9at$ ?r\gh\t ! mass4 ,x has ! peculi> prop]ty ( absorb+ col\r+ matt]1 & is us$ = ?is purpose 9 ! sug> indu/ry & 9 ! prep>ation ( f9e *emicals4 ,phosphoric ,acid4 ,aft] be+ "s "t 9 use1 bone black loses ! prop]ty ( absorb+ col\r+ matt]2 & ?\gh x c be 8reviv$0 sev]al times by heat+ x /rongly 9 a clos$ retort1 x ultimately becomes sp5t & ( no fur!r use to ! sug> ref9]4 ,x is !n heat$ aga91 ?is "t 9 an op5 vessel1 until all ! c>bon is burnt away4 ,! residue is n[ a greyi% solid consi/+ ma9ly ( calcium phosphate4 ,?is1 supplem5t$ ) native phosphate1 :i* is probably fossiliz$ bone1 is us$ = ! prep>ation ( phosphoric acid4 ,! salt is decompos$ by sulphuric acid 9 wood5 vats2 calcium sulphate is =m$1 & ultimately settles on ! bottom ( ! vat1 leav+ a cle> sup]natant liquid1 :i* is a dilute solution ( phosphoric acid4 ,?is liquid is drawn (f & evaporat$ to a syrup4 ,?is is 8syrupy0 phosphoric acid4 ,on be+ /ill m /rongly heat$1 ! syrup loses /ill m wat]1 & a semi-transp>5t glassy-look+ sub/ance1 call$ metaphosphoric acid1 rema9s4 ,sup]phosphate4 ,all f]tile soils1 especially ^? on :i* :eat is to be gr[n1 mu/ conta9 a c]ta9 am\nt ( phosphate4 ,) ?is1 z ) all o!r plant foods1 ! actual p]c5tage weight requir$ 9 ! soil is v small inde$1 b x is necess>y t x %\ld be dissem9at$ ?r\gh\t ! soil4 ,ev5 di/ribution is v difficult to secure 9 ! case ( a sub/ance l calcium phosphate1 :i* is practically insoluble 9 wat]4 ,to get ov] ?is difficulty1 calcium phosphate is conv]t$ into a mixture kn[n z 8sup]phosphate0 by ! foll[+ process4 ,bone a% or ! m9]al phosphate is f9ely gr\nd & ?or\ghly mix$ by ma*9]y ) two-?irds its weight ( sulphuric acid f ! lead *amb]s4 ,aft] a "t1 ?is mixture sets to a h>d mass1 conta9+ pr9cipally gypsum & calcium tetrahydrog5 phosphate4 ,x is !n gr\nd up f9ely & is ready = use4 ,! special modification ( calcium phosphate conta9$ 9 sup]phosphate is soluble 9 wat]4 ,x is1 !re=e1 c>ri$ into ! soil 9 solution1 & 9 ?is way v ev5ly di/ribut$4 ,9 ! soil x reacts ) ! lime or *alk :i* is pres5t1 & is gradually reconv]t$ into insoluble calcium phosphate4 ,! manufacture ( sup]phosphate is a v important indu/ry4 ,! weight ( ! sub/ance produc$ annually 9 ,great ,brita9 alone is n f> bel[ a million tons4 ,basic ,slag4 ,9 ! ,bessem] process = conv]t+ iron into /eel1 ca/ iron is melt$ up 9 a vessel call$ a conv]t] &1 by ! aid ( a p[]ful bla/ bl[n ?r\gh ! molt5 iron1 mo/ ( ! impurities are burnt (f4 ,if1 h[ev]1 phosphorus & sulphur are pres5t1 !y are n remov$ if ! conv]t] has a silica 7acid7 l9+4 ,! orig9al ,bessem] process 01 !re=e1 modifi$ by ,?omas & ,gil*ri/1 & ! conv]t] = ?is k9d ( iron is l9$ ) dolomite & lime 7basic l9+74 ,phosphorus is !n conv]t$ into phosphate & reta9$ by ! l9+1 :i* is subsequ5tly remov$1 gr\nd up f9ely1 & sold z 8basic slag40 ,boric ,acid1 or boracic acid1 is famili> because x is us$ 9 m$ic9e z a mild antiseptic2 x is also employ$ z a pres]vative = food4 ,x is a :ite cry/all9e comp\nd1 sp>+ly soluble 9 wat]4 ,x has no well-m>k$ ta/e1 & causes only a p>tial *ange 9 ! col\r ( litmus solution2 x is1 !re=e1 "o ( ! weak acids4 ,x does n dissolve metals1 b x displaces c>bon dioxide f c>bonates1 =m+ salts4 ,borax1 ! be/ kn[n salt ( boric acid1 is us$ 9 laundry "w & also = mak+ "s enamels1 = :5 x is /rongly heat$ x loses wat]1 & ultimately melts d[n to a cle> 8glass0 9 :i* ! oxides ( metals w dissolve1 yield+ transp>5t sub/ances :i* are beautifully col\r$ accord+ to ! nature ( ! oxide us$4 ,?is prop]ty is (t5 made use ( 9 *emical analysis 9 :at is kn[n z ! 8borax-bead0 te/4 ,illu/ration3 ,fig4 #i4 ,,boric ,,acid ,boric acid is a natural product2 ! me?od by :i* x is obta9$ is ( "s int]e/1 because x is s simple1 & because x %[s h[ m]e traces c be gradually accumulat$ until a v fair total is ultimately obta9$4 ,moreov]1 ! me?od is copi$ directly f ,nature4 ,9 ! e>ly ye>s ( ! n9ete5? c5tury1 c]ta9 jets ( natural /eam1 call$ suffioni1 :i* issue f ! e>? 9 ,tuscany1 7 f\nd to conta9 ! vap\r ( boric acid4 ,^! jets ( /eam are ( volcanic orig94 ,! quantity ( boric acid 9 ! vap\r is v small inde$2 nev]!less1 by ! me?od :i* is adopt$1 x c be pr(itably recov]$1 & m ?an a ton ( ! solid is daily produc$4 ,9 ! same c\ntry !re are _m lagoons1 ! wat] ( :i* conta9s boric acid4 ,x 0 rightly conjectur$ t ?is boric acid came f jets ( /eam :i* issu$ f ! e>? 9 ! b$ ( ! lagoon4 ,?is sugge/$ ! idea ( build+ up an artificial lagoon ar\nd a gr\p ( jets4 ,s]ies ( ab\t five ( ^! collect+ bas9s 7,fig4 #i7 are =m$1 ea* "o at a slightly l[] level ?an ! "o :i* prec$es x4 ,! fir/ bas9 is fill$ ) wat] f an adjac5t spr+1 & ?is is all[$ to rema9 = tw5ty-f\r h\rs4 ,a sluice is !n op5$ & ! liquid conta9$ 9 ! fir/ bas9 fl[s d[n to ! second1 :]e x rema9s = ano!r day1 & s on until x rea*es ! la/ bas9 ( ! s]ies4 ,! liquid by ?is "t is almo/ fully *>g$ ) boric acid1 b x conta9s only ab\t #b p] c5t41 because ! acid is s sp>+ly soluble 9 wat]4 ,f ! la/ bas9 7,a71 ! liquid runs into l>ge vats 7,b1 ,d71 :]e ! susp5d$ impurities settle d[n4 ,! solution ( boric acid is !n conc5trat$ by caus+ x to fl[ ov] a broad incl9$ plane made ( corrugat$ lead or ?r\gh a s]ies ( %all[ vessels heat$ by jets ( natural /eam4 ,! hot liquid fl[s into ano!r vat 7,c71 &1 z x cools1 boric acid cry/allizes out & is remov$ by p]=at$ ladles4 ,! "m liquor f :i* ! cry/als h be5 )drawn is1 ( c\rse1 a cold saturat$ solution ( ! acid1 & ?is is return$ to ! top ( ! incl9e to fl[ d[n aga9 & lose m wat]4 ,! boric acid is f9ally transf]r$ to dry+ *amb]s1 :i* are also heat$ by ! natural /eam4 ,native borax or 8t9kal0 comes f ,?ibet & also f ,ceylon4 ,9 ,cali=nia1 a l>ge quantity ( borax is obta9$ f a borax lake1 & also f ! mud ( m>%es 9 its neighb\rhood4 ,silica4 ,! elem5t silicon does n occur 9 ! free /ate 9 ,nature1 nei!r has any p>ticul> use be5 f\nd = x1 & !re=e x is n (t5 isolat$ except to provide a lecture specim54 ,! comp\nds ( silicon1 h[ev]1 are bo? pl5tiful & important1 especially silica1 ! oxide1 & ! silicates or salts ( silicic acid4 ,! commone/ =ms ( silica are s&1 fl9t1 & qu>tz4 ,silv] s& is compos$ ( small cry/als ( pure silica1 :ile fl9t is ! amorph\s v>iety ( ! same sub/ance4 ,qu>tz1 or rock cry/al1 is a v h>d & transp>5t m9]al4 ,x =ms six-sid$ prisms end+ 9 pyramids4 ,x is di/+ui%$ f o!r common transp>5t m9]als1 su* z calcsp>1 by ! fact t x _c be scrat*$ ev5 ) a good knife or file1 & t a drop ( hydro*loric acid has no action on x4 ,! melt+ po9t ( silica is v high4 ,sometimes silica is v delicately col\r$ ) m9ute traces ( metallic oxides & o!r sub/ances1 & ^! =ms1 because ( _! r>ity & beauty1 are m highly valu$4 ,smoky qu>tz1 cat's-eye1 & ame?y/ are "s ( ! col\r$ v>ieties ( qu>tz4 ,opal1 agate1 jasp]1 onyx1 & *alc$ony are1 9 ! *emi/'s classification1 m]ely col\r$ fl9ts4 ,9 rec5t ye>s1 *emical app>atus has be5 made f pure fus$ silica4 ,?is c only be work$ 9 ! oxy-hydrog5 bl[-pipe flame or 9 ! electric furnace2 nev]!less1 crucibles1 flasks1 beak]s1 & retorts c be made4 ,silica w>e has sev]al advantages ov] glass1 notably1 t wat] has no action ^u x at all2 moreov]1 its coeffici5t ( expansion is s v small t a piece ( app>atus made ( silica c be sudd5ly heat$ or cool$ )\t risk ( fracture2 inde$1 x c be made r$-hot & cool$ imm$iately by plung+ into cold wat]4 ,qu>tz or silica fibres1 us$ = susp5d+ magnets & o!r bodies 9 v delicate physical app>atus1 are made 9 ! foll[+ way4 ,molt5 silica is atta*$ to ! bolt ( a crossb[1 :i* is !n releas$ above a c>pet ( black velvet4 ,z ! bolt flies =w>d1 x draws out ! silica into a filam5t1 :i* is s f9e t x w\ld be difficult to f9d 7 x n = ! velvet backgr\nd4 ,silicic ,acid itself is only ( !oretical int]e/4 ,x is obta9$ by add+ hydro*loric acid to a solution ( potassium or sodium silicate4 ,x is a gelat9\s sub/ance ( some:at indef9ite composition4 ,x has no effect on litmus1 no ta/e1 & no solv5t action2 9 fact1 x is only recognizable z an acid because x dissolves 9 alkalis1 =m+ salts call$ silicates4 ,x is "o ( ! weake/ acids kn[n4 ,! natural silicates are v abundant & v>i$2 or?oclase or pota% felsp>1 & albite or soda felsp>1 are ^? :i* mo/ commonly occur4 ,! =m] is potassium alum9ium silicate1 & ! latt]1 sodium alum9ium silicate4 ,iron is g5]ally pres5t 9 bo? z an impurity4 ,! wea!r+ ( ! felsp>s1 9 conjunction ) ! action ( wat]1 has produc$ ! clays4 ,9 ?is way1 pure :ite ,*9a clay has be5 =m$ f felsp>s :i* conta9 little or no iron1 & ! co>s] k9ds ( clay f o!rs conta9+ a great] proportion ( =eign sub/ances4 ,mica1 :i* is us$ = mak+ lamp *imneys1 is a potassium alum9ium silicate4 ,asbe/os1 me]s*aum1 b]yl1 g>net1 jade1 & hornbl5de are all silicates ( v>i\s metals4 ,glass is a complex mixture ( insoluble silicates ) excess ( silica4 ,! v>ieties 9 common use are soda glass1 ,bohemian glass1 & lead glass 7:i* is also call$ fl9t glass74 ,soda glass is ma9ly a mixture ( calcium & sodium silicates1 & is di/+ui%$ by its l[ melt+ po9t1 :i* makes x easy to "w at mod]ate temp]atures4 ,x appe>s 9 comm]ce z plate glass1 w9d[ glass1 & common bottles4 ,bohemian glass conta9s calcium & potassium silicates1 & has a high melt+ po9t4 ,x is us$ = mak+ *emical app>atus4 ,lead or fl9t glass conta9s ! silicates ( lead & potassium2 ?is is a d5se glass1 b at ! same "t r s(t4 ,x takes a high poli% & is us$ = mak+ ornam5tal or cut-glass w>e4 ,rememb]+ t glass is compos$ ( ! salts ( silicic acid1 ! read] w readily und]/& t ! mixture f :i* x is made mu/ conta9 acidic & basic con/itu5ts4 ,! acidic or acid-=m+ mat]ial is 9 e case silica or s&4 ,?is mu/ be pure1 & = all b ! commone/ k9d ( bottle or w9d[ glass1 x mu/ be free f iron1 o!rwise ! glass w h a m or less pron\nc$ gre5i% col\r4 ,x mu/ also be f9e & ev5 gra9$4 ,=m]ly1 ! glass s&s us$ 9 ?is c\ntry came f ,holl& & ,belgium1 b n[ supplies f sev]al ,briti% s\rces are be+ successfully us$4 ,! basic portion ( ! glass mixture diff]s accord+ to ! k9d ( glass requir$4 ,an av]age mixture = soda glass conta9s s&1 #bj p>ts2 salt cake 7sodium sulphate71 #aj p>ts2 quicklime1 #e p>ts2 *>coal1 #a "p4 ,= ,bohemian glass1 pe>l a% 7potassium c>bonate7 takes ! place ( salt cake1 & no *>coal is necess>y because ! mat]ials us$ are f9]4 ,= lead glass1 ! mixture is /ill fur!r modifi$ by ! use ( li?>ge1 or m (t5 r$ lead1 9 place ( lime4 ,! +r$i5ts are well mix$ & ?or\ghly dri$4 ,wa/e glass f a previ\s bat* is also add$4 ,! mixture is heat$ to ab\t #abjj ,c4 9 l>ge pots made ( ,/\rbridge clay1 & ! heat+ is cont9u$ = z mu* z sixte5 h\rs1 & until ! :ole ( ! mat]ial 9 ! pot is molt5 & fairly mobile4 ,scum or glass-gall is remov$1 & :5 gas bubbles h disappe>$1 ! temp]ature is all[$ to fall to #gjj-hjj1 :5 ! glass becomes suffici5tly visc\s = subsequ5t work+4 ,! semi-fluid mass is !n bl[n1 m\ld$1 or drawn1 accord+ to ! k9d ( article t is requir$4 ,! physical prop]ties ( glass w n[ be consid]$ 9 ord] t we may be able to acc\nt = its ext5d$ use4 ,su* an inquiry z ?is1 especially 9 ! case ( mat]ials 9 common use1 is (t5 int]e/+1 because x frequ5tly happ5s t ! special prop]ty ^u :i* we set s mu* value is an abnormal "o &1 consequ5tly1 ! feature :i* we take = grant$ is precisely ! "o into :i* we %\ld inquire mo/ closely4 ,! mo/ /rik+ feature ( glass is its transp>5cy4 ,?is prop]ty is abnormal1 if glass is a solid4 ,consid] :at happ5s 9 mo/ cases4 ,a sub/ance l nitre melts easily & 9 ! molt5 /ate is p]fectly transp>5t2 :5 x cools1 cry/als =m &1 ?\gh ^! individually may be transp>5t1 yet ! solid mass is opaque4 ,! reason = ?is is t ! solid is n optically homog5e\s1 & !re=e a ray ( light _c pass ?r\gh x 9 a /raight l9e4 ,at ea* facet ( a cry/al light is deviat$ & reflect$1 & 9 ! end is almo/ :olly scatt]$4 ,consequ5tly1 an object1 ev5 if x c be se5 at all1 c be disc]n$ only 9 a blurr$ & indi/9ct fa%ion ?r\gh su* a m$ium4 ,!re are v good reasons1 h[ev]1 = suppos+ t glass is n a true solid b an extremely visc\s liquid4 ,if glass is heat$1 x s(t5s & beg9s to fl[ v sluggi%ly at fir/1 b aft]w>ds m readily4 ,!re is no abrupt *ange1 z !re g5]ally is 9 pass+ f ! solid to ! liquid /ate4 ,simil>ly 9 cool+1 !re is no po9t at :i* x is possible to say t ! glass is solidify+4 ,! view t ?is sub/ance is really a liquid is p]haps a little />tl+ at fir/1 b x becomes less s :5 we obs]ve t a long glass rod support$ at its ends 9 a horizontal position sags 9 ! middle & is p]man5tly de=m$4 ,to avoid t *ange :i* w\ld be te*nically call$ solidification by a sci5ti/1 ! article :i* has be5 fa%ion$ 9 glass is cool$ d[n v sl[ly & gradually4 ,?is "p ( ! process is call$ anneal+2 x may occupy "s days 9 extreme cases1 & x po9ts to ! fact t exp]i5ce has %[n t x is necess>y to gu>d aga9/ "s *ange :i* w\ld normally take place if ?is precaution 7 neglect$4 ,! *ange 9 glass :i* anneal+ is int5d$ to prev5t is kn[n z devitrification4 ,9 spite ( all precautions1 ?is does occur sometimes1 & specim5s ( old w9d[ glass are (t5 se5 to h lo/ _! transp>5cy completely & to h an opalesc5t %e54 ,9 ^! cases1 ! silicates h cry/alliz$4 ,an extreme case ( badly anneal$ glass is illu/rat$ by ,rup]t's drops1 a sci5tific curiosity ( v old /&+4 ,^! are 8te>s0 ( glass made by dropp+ ! molt5 sub/ance into wat]4 ,:5 ! tail ( ! drop is nipp$ (f1 ! :ole ?+ is %att]$ to p[d] ) some?+ l explosive viol5ce4 ,cle>ly !re is a v great int]nal /ra91 due to ! fact t ! out] p>ts h solidifi$ & contract$1 :ile ! inn] "p is /ill w>m & dilat$4 ,ano!r rem>kable feature ( glass is ! ease & simplicity ) :i* x c be fa%ion$ into articles ( v>i\s %apes4 ,z a pla/ic mat]ial1 molt5 glass almo/ ranks ) clay4 ,?is aga9 is due to ! prop]ty ( pass+ ?r\gh a visc\s /ate1 t is1 "o :i* is int]m$iate betwe5 a solid & a liquid4 ,wat] ,glass1 or soluble glass1 is ma9ly sodium silicate4 ,x is made by fus+ s& or p[d]$ fl9t ) cau/ic or ) mild soda2 sometimes1 by dige/+ cru%$ fl9t or *]t ) cau/ic soda solution "u consid]able pressure 9 autoclaves or specially con/ruct$ boil]s4 ,9 ! latt] case1 no extraction is necess>y2 b 9 ! =m]1 ! residue is treat$ ) wat] & ! solution evaporat$ until x becomes a visc\s transp>5t liquid4 ,?is liquid is us$ 9 v>i\s ways 9 indu/ry4 ,x is add$ to ! *eap] v>ieties ( yell[ soap1 & is employ$ z a mordant 9 dye+ & pr9t+ calico4 ,an artificial s&/one is made by mix+ s&1 calcium *loride1 & sodium silicate2 ! two la/-nam$ sub/ances int]act to =m calcium silicate1 :i* is insoluble 9 wat]4 ,= dome/ic purposes1 wat] glass is be/ kn[n 9 connection ) ! pres]v+ ( eggs4 ,:5 ! film ( wat] glass dries on ! surface ( ! egg %ell1 ! latt] becomes imp]vi\s to air4 ,,*apt] ,,vii ,,organic ,,acids ,organic ,*emi/ry4 ,ab\t a c5tury ago1 :5 ! sci5ce ( ,*emi/ry 0 /ill 9 its infancy1 sev]al sub/ances 7 kn[n :i* c\ld !n only be obta9$ f animals or plants4 ,! composition ( ^! sub/ances 0 n und]/ood1 & !y 7 n classifi$2 moreov]1 s9ce none ( !m _h ev] be5 prep>$ artificially1 x 0 suppos$ t x 0 impossible to d ?is--! reason giv5 0 t 8vital =ce0 0 necess>y = _! production4 ,9 "t1 h[ev]1 "s ( ! mo/ typical animal & vegetable products 7 prep>$ 9 ! laboratory1 & ! belief 9 vital =ce disappe>$4 ,9 lat] times x 0 prov$ t sub/ances l sug>1 />*1 urea1 indigo1 & a great _m m1 all conta9 ! elem5t c>bon4 ,at ! pres5t "t1 m ?an #ajj1jjj comp\nds ( ?is elem5t are kn[n2 & s9ce !y resemble "o ano!r1 & at ! same "t diff] 9 sev]al important respects f ! comp\nds ( o!r elem5ts1 x is bo? natural & conv5i5t t !y %\ld be class$ toge!r & /udi$ sep>ately4 ,?is bran* ( ,*emi/ry is call$ organic4 ,x mu/ n1 h[ev]1 be suppos$ t all organic comp\nds are necess>ily produc$ by "s liv+ organism4 ,a great _m are1 b !re are _m m :i* are purely syn!tic products4 ,inorganic ,*emi/ry includes all ! o!r elem5ts & _! d]ivatives4 ,! elem5t c>bon1 & also "s ( its simpl] comp\nds1 su* z c>bon monoxide1 c>bon dioxide1 c>bonic acid1 & c>bonates1 are m appropriately plac$ 9 ! inorganic section4 ,! acids :i* h be5 consid]$ up to ?is po9t are all inorganic acids1 & ^? :i* foll[ are organic4 ,sulphuric1 nitric1 & hydro*loric acids are (t5 di/+ui%$ z ! m9]al acids 9 contradi/9ction to oxalic1 citric1 t>t>ic1 & "s o!rs :i* 7 fir/ obta9$ f unripe fruits & !re=e call$ vegetable acids4 ,organic acids h all ! g5]al prop]ties ( ! class1 b !y are mu* weak] ?an ! m9]al acids m5tion$ above4 ,?is is %[n by _! solv5t action on metals1 oxides1 & c>bonates1 :i* is 9 all cases slight4 ,v9eg> is ! trade "n = :at is ess5tially a dilute solution ( acetic acid :i* has be5 made by ! acet\s f]m5tation ( sac*>9e fluids conta9+ weak alcohol4 ,9 addition to acetic acid1 v9eg> conta9s m9ute quantities ( a l>ge numb] ( comp\nds4 ,"s ( ^! help to produce t agreeable flav\r & aroma :i* di/+ui%es v9eg> f dilut$ acetic acid4 ,! nature & quantity ( ! flav\r+ con/itu5ts dep5d ma9ly ^u ! nature ( ! alcoholic solution us$4 ,s9ce ! acetic acid 9 v9eg> is always produc$ by f]m5tation1 all processes = ! manufacture ( v9eg> are ess5tially arrangem5ts = promot+ ! vigor\s gr[? & developm5t ( ,mycod]ma aceti1 ! organism :i* produces ! v9eg> f]m5t4 ,l all o!r plants1 ,mycod]ma aceti w fl\ri% only "u c]ta9 fav\rable conditions4 ,9 ! fir/ place1 x requires n\ri%m5t1 & !re=e c]ta9 nitrog5 comp\nds & salts mu/ be pres5t 9 ! alcoholic solution4 ,^! are conta9$ 9 w9es1 be]1 cid]1 & malt liquors1 b n 9 spirits ( w9e1 :i* is pure alcohol di/ill$ f liquids :i* h und]gone v9\s f]m5tation4 ,if ! plant is plac$ 9 dilute spirits ( w9e1 only a v little acetic acid is =m$1 & !n ! action ceases because ! solution does n conta9 ! necess>y food sub/ances4 ,temp]ature also has a v m>k$ effect on gr[?1 ! mo/ fav\rable range be+ betwe5 #fh & #ie ,f4 ,alcohol is *ang$ to acetic acid by ! process ( oxidation1 & !re=e1 9 mak+ v9eg>1 arrangem5ts h to be made to br+ toge!r weak alcohol & air 9 ! pres5ce ( ! plant4 ,! f]m5t :i* is secret$ by ! plant !n causes an accel]ation ( ! reaction4 ,!re is a consid]able am\nt ( simil>ity betwe5 f]m5tation & contact action4 ,9 ?is connection1 x is int]e/+ to note t ! conv]sion ( alcohol into acetic acid c also be br\ght ab\t by expos+ a mixture ( alcohol vap\r & air to ! action ( plat9um black2 9 fact1 !re is "o process = mak+ v9eg> 9 ?is way4 ,fr5* ,v9eg>4 ,new w9e1 especially t :i* conta9s a l[ p]c5tage ( alcohol1 is liable to _m k9ds ( 8sickness40 ,x may turn bitt]1 x may turn s\r1 or x may und]go :at is call$ lactic f]m5tation4 ,9 ei!r case1 x becomes unsaleable z a bev]age4 ,w9e :i* has turn$ s\r is ! be/ mat]ial = mak+ v9eg>1 & :5 ?is is done by ! ,fr5* or sl[ process1 a product ) a v f9e b\quet is obta9$4 ,! me?ods adopt$ are v simple4 ,=m]ly1 ! w9e 0 p\r$ into b>rels leav+ ! top portion empty1 & provid+ = a curr5t ( air ov] ! surface4 ,! b>rels 7 (t5 set up 9 r[s 9 ! op5 air 9 an enclosure :i* 0 !n kn[n z a 8v9eg> field40 ,! process ( s\r+ :i* _h already begun w5t on naturally1 & 9 ! c\rse ( a few mon?s1 ne>ly ! :ole ( ! alcohol 0 conv]t$ into acetic acid4 ,! process n[ 9 use 9 "s ( ! ,fr5* factories is some:at simil>4 ,l>ge casks hold+ ab\t #ajj gallons are set up 9 a room1 & provision is made = keep+ ! temp]ature uni=m4 ,ea* cask is fir/ acidulat$ by all[+ /rong v9eg> to /& 9 x until ! v9eg> plant has develop$ on ! surface4 ,! casks are !n fill$ up v gradually by add+ a few gallons ( w9e e eight or t5 days4 ,:5 ! cask is full1 a fraction ( ! cont5ts is drawn (f & replac$ by w9e4 ,! process !n becomes cont9u\s1 until x is necess>y to clean out ! g5]ator & />t aga94 ,9 rec5t times1 ! manufacture ( w9e v9eg> has be5 c>ri$ out on m sci5tific pr9ciples4 ,! v9eg> plant is actually cultivat$ & exam9$ microscopically be=e be+ us$1 9 ord] to make sure ( ! abs5ce ( m\lds & bact]ia1 :i* set up o!r f]m5tations1 produc+ sub/ances :i* affect adv]sely ! ta/e & aroma ( ! f9i%$ product4 ,! cultivat$ f]m5t is !n add$ to ! w9e 9 %all[ vessels & ! process is c>ri$ on z describ$ above4 ,malt ,v9eg>4 ,a dilute solution ( alcohol :i* is made f malt by f]m5tation ) yea/ conta9s ! nutritive sub/ances necess>y = ! gr[? ( ! v9eg> plant1 & c !re=e be us$ z a />t+-po9t = ! manufacture ( v9eg>4 ,spr\t$ b>ley or malt is mix$ ) oats1 b>ley1 rice1 or o!r />*-conta9+ mat]ial4 ,! mixture is ma%$ ) w>m wat] & !n f]m5t$ ) yea/1 giv+ :at is call$ 8raw _s40 ,?is is conv]t$ into v9eg> by ! 8quick0 process4 ,! v9eg> g5]ator 7,fig4 #aj7 is a l>ge b>rel divid$ into ?ree comp>tm5ts by two p]=at$ p>titions4 ,! l[] disc is fix$ ab\t "o-?ird ( ! way up ! b>rel1 & ne> x holes are bor$ to admit air4 ,! upp] disc1 fix$ ne> ! top ( ! b>rel1 is p]=at$ ) a l>ge numb] ( small holes :i* are p>tially /opp$ up ) %ort ?reads or wicks1 :i* hang f ! "u side4 ,! space betwe5 ! two discs is pack$ ) specially prep>$ bee* %av+s1 :i* h be5 left to /& 9 /rong v9eg> until !y are cov]$ ) ! v9eg> plant4 ,illu/ration3 ,fig4 #aj4 ,,quick ,,v9eg> ,,process ,! weak _s is deliv]$ into ! upp] portion ( ! b>rel & is di/ribut$ 9 v small drops by ! ?reads2 x !n passes sl[ly ov] ! v9eg> plant1 to :i* ! air also has free access4 ,:5 x rea*es ! bottom1 x ov]fl[s into a res]voir & is aga9 pass$ ?r\gh ! g5]ator2 ?is is repeat$ until ! product conta9s ! desir$ am\nt ( acetic acid4 ,! pr9ciple ( ! quick v9eg> process is ! same z t employ$ 9 mak+ w9e v9eg>4 ,! spe$ ( ! reaction is1 h[ev]1 greatly increas$ by hav+ ! f]m5t spread ov] a v l>ge surface & by ! free circulation ( air4 ,x is possible to make w9e v9eg> by ! quick process1 b x is n done1 because ! product is inf]ior 9 ta/e & aroma to t made by ! sl[ process4 ,bo? w9e v9eg> & malt v9eg> :5 fre%ly prep>$ h a /upefy+ & unpleasant od\r4 ,be=e ! product is ready = ! m>ket1 x has to be matur$ 9 b>rels4 ,dur+ ?is process1 a small quantity ( alcohol :i* /ill rema9s 9 ! v9eg> comb9es sl[ly ) "s ( ! acetic acid1 produc+ acetic e/]1 a sub/ance :i* has a pleasant fruity od\r4 ,! col\r ( w9e v9eg> is natural1 b v9eg> :i* is produc$ by ! quick process is col\rless or only fa9tly col\r$4 ,s9ce ! public has a pref]5ce = v9eg> :i* is br[n 9 col\r1 ! product ( ! quick process is col\r$ artificially1 ei!r by add+ c>amel or by prep>+ ! weak _s f malt :i* has be5 slightly *>r$ 9 dry+4 ,indu/rial ,acetic ,acid4 ,! solutions ( acetic acid dealt ) above w\ld be too dilute = any indu/rial purpose2 moreov]1 ! acid c be obta9$ mu* m *eaply by ! di/illation ( wood4 ,:5 wood is subject$ to a high temp]ature1 x is conv]t$ into *>coal &1 at ! same "t1 an inflammable gas1 an acid liquid1 & t> are giv5 (f1 & c be collect$ 9 suitable vessels4 ,! foll[+ table1 on page #gc1 gives ! relative am\nts ( ! v>i\s sub/ances obta9$ f wood by dry di/illation4 ,! quantities are ^? d]iv$ f "o cord1 t is1 #abe cu4 ft4 ,*>coal ,alcohol ,calcium ,t> 9 ,wood oil ,turp5t9e 9 9 acetate gallons4 9 gallons4 bu%els4 gallons4 9 lbs4 gallons4 ,h>d #dj-ej #h-ab #aej-bjj #h-bj woods ,res9\s #be-dj #b-d #ej-ajj #cj-fj #cj-fj ,heavy woods woods #ab-be ,light woods #b-aj ,sawdu/ #be-ce #b-d #de-ge ,! aque\s liquid t di/ils ov] conta9s me?yl alcohol 7wood _s71 acetone1 & acetic acid4 ,! crude mixture is kn[n z pyroligne\s acid4 ,?is is neutraliz$ ) milk ( lime or soda a%1 :i* conv]ts acetic acid into calcium or sodium acetate1 b has no action on ! me?yl alcohol & acetone :i* are also pres5t4 ,! mixture is !n di/ill$1 :5 me?yl alcohol1 acetone1 & wat] pass ov] into ! di/illate1 leav+ ! acetate 9 ! retort4 ,to obta9 ! free acid f ! acetate1 ! latt] is well dri$ & !n di/ill$ ) conc5trat$ sulphuric acid4 ,acetic acid1 be+ ! m volatile ( ! two acids1 di/ils ov]1 & is ne>ly pure4 ,! me?od ( remov+ ! la/ traces ( wat] dep5ds ^u ! fact t acetic acid solidifies at #ag ,c4 ,! acid1 :i* is ne>ly1 b n q1 free f wat]1 is cool$ until a portion solidifies4 ,! "p :i* /ill rema9s liquid is p\r$ away1 & ! process is repeat$ until a residue is obta9$ :i* solidifies z a :ole4 ,?is is glacial acetic acid1 s call$ because x is a mass ( gli/5+ plates :i* look l newly-=m$ ice4 ,! ,acetates ,alum9ium ,acetate1 made by dissolv+ alum9a 9 acetic acid1 is ! 8r$ liquor0 :i* is us$ z a mordant 9 dye+4 ,x is a col\rless liquid1 b is call$ 8r$ liquor0 because x is us$ ) dyes :i* give a r$ col\r4 ,f]r\s ,acetate1 made 9 a simil> way f scrap iron & acetic acid1 is ! 8black liquor0 us$ 9 dye+4 ,v]digris1 or basic copp] acetate1 is a valuable pigm5t4 ,x is made by int]pos+ clo?s soak$ 9 v9eg> betwe5 plates ( copp]4 ,aft] ! action has be5 all[$ to g on = a long "t1 ! plates are wa%$ ) wat] & ! v]digris is scrap$ (f4 ,! f9e/ v]digris is made 9 ,france 9 ! w9e-produc+ di/rict ar\nd ,montpelli]4 ,"h1 in/ead ( clo?s soak$ 9 v9eg>1 ! solid residue f ! w9e presses is spread 9 lay]s betwe5 ! copp] plates4 ,! product made 9 ?is way is call$ v]t de ,montpelli]4 ,illu/ration3 ,fig4 #aa4 ,,dut* ,,process ,,= ,,:ite ,,lead ,v]digris1 l all ! copp] comp\nds1 is extremely poison\s4 ,x is v liable to be =m$ on ! surface ( copp] ut5sils us$ = cook+ purposes4 ,lead ,acetate1 or sug> ( lead1 is us$ 9 l>ge quantities 9 ! col\r indu/ry = mak+ v>i\s r$s & yell[s4 ,x is prep>$ by dissolv+ ! metal or its oxide 7li?>ge7 9 acetic acid4 ,! sl[ action :i* acetic acid vap\r has ^u ! metal lead f9ds a v int]e/+ application 9 :at is kn[n z ! ,dut* process = ! manufacture ( :ite lead#d = pa9t4 ,! metal is ca/ into grids or spirals1 :i* are plac$ on ! %\ld]s ( ! specially made pots sket*$ 9 ,fig4 #aa4 ,a little dilute acetic acid is p\r$ into ea* ( ! pots1 :i* are !n arrang$ side by side on a ?ick lay] ( tan b>k1 /able manure1 or o!r mat]ial :i* w heat by f]m5tation4 ,! fir/ lay] ( pots is !n bo>d$ ov]2 ano!r lay] ( pots is plac$ ^u ?is1 & s on1 ti] ^u ti]1 until ! %$ is q full4 ,! heat develop$ by ! f]m5t+ mat]ial vaporizes ! acetic acid1 & ?is vap\r corrodes ! lead1 =m+ basic lead acetate4 ,! c>bon dioxide :i* is also produc$ dur+ f]m5tation conv]ts ! acetate into ! c>bonate1 :i* falls z a heavy :ite p[d] into ! pots4 ,future ,supply ( ,acetic ,acid4 ,:5 all ! op]ations involv$ 9 ! production ( acetic acid f wood1 f ! fell+ ( ! tree to ! f9al sep>ation ( ! glacial sub/ance1 are tak5 into consid]ation1 x w be readily und]/ood h[ x is t ?is acid has nev] be5 *eap :5 comp>$ ) o!r acids us$ on an equally l>ge scale4 ,9 addition to ?is1 ! competition = wood = pap]-mak+ & = ! v num]\s cellulose indu/ries is rapidly increas+4 ,x is1 !re=e1 n surpris+ to le>n t *emi/s h turn$ _! att5tion t[>ds ! discov]y ( new] & *eap] me?ods ( mak+ acetic acid4 ,su* a process seems to h be5 work$ out 9 ,g]many4 ,! />t+-po9t is acetyl5e gas made by ! action ( wat] on calcium c>bide4 ,:5 ?is gas is pass$ ?r\gh sulphuric acid conta9+ susp5d$ m]curic oxide or dissolv$ m]cury salt1 ! acetyl5e is oxidiz$ fir/ to aldehyde & !n to acetic acid4 ,if ?is process %\ld prove to be successful1 x w =m ! />t+-po9t ( a new & important indu/ry1 =1 ap>t f ! l>ge am\nt ( acetic acid :i* is us$ 9 comm]ce1 !re is ! production ( ! v important solv5t kn[n z acetone1 :i* c be made f acetic acid by a v simple op]ation4 ,t>t>ic ,acid4 ,grape juice conta9s a l>ge quantity ( potassium hydrog5 t>trate dissolv$ 9 x2 :5 ! liquid is f]m5t$ & alcohol is =m$1 ?is salt cry/allizes out because x is n soluble 9 alcohol4 ,aft] ! new w9e has be5 p\r$ (f1 ! salt is f\nd z a br[ni% cry/all9e residue adh]+ to ! sides ( ! vat4 ,also ! salt goes on cry/alliz+ aft] ! w9e is put into b>rels1 & =ms an incru/ation on ! sides4 ,?is is call$ ! lees or s$im5t ( w9e4 ,9 comm]ce1 ! sub/ance is kn[n z argol 7sometimes spelt argal71 & also t>t> ( w9e4 ,crude argol is purifi$ by dissolv+ x 9 wat] & de/roy+ ! col\r by boil+ ) animal *>coal4 ,:5 ! cle> liquid obta9$ f ?is mixture by filtration is evaporat$1 a :ite cry/all9e sub/ance sep>ates out4 ,?is is potassium hydrog5 t>trate or cream ( t>t>4 ,t>t>ic acid is obta9$ f cream ( t>t>4 ,! salt is dissolv$ 9 wat] & ne>ly neutraliz$ ) milk ( lime4 ,insoluble calcium t>trate is precipitat$1 & potassium t>trate rema9s 9 solution4 ,a fur!r quantity ( calcium t>trate is obta9$ by add+ calcium *loride to ! solution j m5tion$4 ,! two precipitates ( calcium t>trate are !n mix$ & decompos$ by dilute sulphuric acid1 & aft] ! calcium sulphate is filt]$ (f1 t>t>ic acid is obta9$ z a solid by evaporat+ ! cle> liquid4 ,! g5]al prop]ties ( t>t>ic acid are well kn[n4 ,x is soluble 9 wat]1 giv+ a solution :i* has a pleasantly acid ta/e4 ,citric ,acid4 ,! %>p flav\r ( _m unripe fruits is due to ! pres5ce ( citric acid2 ! juice ( lemons conta9s #e-f p] c5t4 ( ! acid4 ,! free acid is obta9$ 9 a mann] precisely simil> 9 pr9ciple to t describ$ = t>t>ic acid4 ,oxalic ,acid4 ,oxalic acid & its salts1 ! oxalates1 are v widely di/ribut$ 9 ! vegetable k+dom4 ,^! comp\nds are pres5t 9 wood sorrel 7,oxalis acetosella71 9 rhub>b1 9 dock1 & 9 _m o!r plants4 ,! acid is made on a l>ge scale by mix+ p9e sawdu/ to a /iff pa/e ) a solution conta9+ cau/ic soda & pota%4 ,! pa/e is spread out on iron plates & heat$1 c>e be+ tak5 n to heat ! mixture to ! po9t at :i* x *>s4 ,! mass is !n all[$ to cool1 & is mix$ ) a small quantity ( wat] to dissolve out ! excess ( alkali4 ,?is is recov]$ & us$ aga94 ,sodium oxalate1 :i* is ! ma9 product ( ! reaction describ$ above1 is dissolv$ 9 wat] & treat$ ) milk ( lime1 :]eby insoluble calcium oxalate is obta9$1 :i* is subsequ5tly decompos$ ) sulphuric acid1 yield+ oxalic acid4 ,potassium hydrog5 oxalate is sometimes call$ salts ( sorrel1 & potassium quadroxalate1 salts ( lemon4 ,! mo/ famili> use ( ! latt] sub/ance is 9 ! removal ( ink /a9s4 ,oxalic acid & its salts are poison\s4 ,! free acid has sometimes be5 mi/ak5 = sug> ) fatal results4 ,=mic ,acid 7,l4 =mica1 an ant7 is f\nd bo? 9 ! vegetable & 9 ! animal k+dom4 ,if ! leaf ( a /++ nettle is exam9$ ) a microscope1 x is se5 to be cov]$ ) long po9t$ hairs hav+ a gl& at ! base4 ,?is gl& conta9s =mic acid4 ,:5 ! nettle is t\*$ lightly1 ! f9e po9t ( ! hair punctures ! sk91 & a subcutane\s injection ( =mic acid is made1 :i* quickly raises a bli/]4 ,! inconv5i5ce :i* arises f ! /+s ( bees & wasps1 also f ! fluid eject$ by ants :5 irritat$1 is due to =mic acid4 ,! rem$y 9 ea* case is ! same2 ! acid mu/ be neutraliz$ z quickly z possible ) mild alkali1 su* z wa%+ soda4 ,=mic acid 0 fir/ made by di/ill+ an infusion ( r$ ants4 ,x is n[ made f glyc]9e & oxalic acid4 ,! ,fatty ,acids4 ,animal fats & vegetable oils are simil>ly con/itut$ bodies4 ,!y are compos$ ma9ly ( ?ree *emical comp\nds kn[n z /e>91 palmit91 & olen4 ,( ^!1 /e>9 & palmit9 are solids at ord9>y temp]atures1 :ile olen is a liquid4 ,h>d fats l ^? ( mutton & beef are compos$ ma9ly ( /e>92 fats ( m$ium h>dness conta9 /e>91 palmit91 & "s olen2 :ile oils su* z cod-liv] oil & olive oil are ne>ly pure olen4 ,/e>91 palmit91 & olen are analog\s 9 composition to salts4 ,_! proximate con/itu5ts are glyc]9e & c]ta9 organic acids1 /e>ic1 palmitic1 & olec respectively4 ,9 ord] to obta9 ! fat free f tissue :i* x conta9s 9 its natural /ate1 x is ti$ up 9 a musl9 bag & heat$ 9 boil+ wat]4 ,! fat is squeez$ out ?r\gh ! me%es ( ! fabric & floats on ! surface ( ! wat] z an oil :i* solidifies on cool+4 ,?is cl>ifi$ fat is call$ tall[4 ,all fats & vegetable oils c be resolv$ into _! two con/itu5ts1 ! acid & ! glyc]9e4 ,?is c be br\ght ab\t by heat+ ! fat ) wat] to ab\t #bjj ,c4 ,?is op]ation mu/ be c>ri$ out 9 a vessel capable ( )/&+ pressure & clos$ ) a safety valve2 o!rwise1 ! requisite temp]ature c\ld n be obta9$4 ,aft] ?is treatm5t1 !re is left 9 ! vessel an oily lay] :i* solidifies on cool+ & an aque\s lay] :i* conta9s ! glyc]9e4 ,! solidifi$ oily lay] is ! fatty acid4 ,9 ! case ( mutton or beef tall[1 x w\ld be ma9ly a mixture ( /e>ic & palmitic acids4 ,?is mixture is us$ to make 8/e>90 c&les4 ,! acids !mselves are wax-l solids )\t any di/9ctive ta/e4 ,/e>ic acid melts at #fi ,c4 & palmitic at #fb ,c4 ,!y h no p]ceptible action on ! col\r ( litmus1 nei!r h !y any solv5t action on metals or c>bonates4 ,we %\ld n recognize ^! sub/ances z acids at all 7 x n = ! fact t !y comb9e ) alkalis1 =m+ salts4 ,! salts ( ! fatty acids are call$ soaps4 ,to make soap1 ! fat is boil$ ) cau/ic alkali or cau/ic lye1 z x is m (t5 call$4 ,?is breaks ! fat up prim>ily into ! acid & glyc]9e2 b 9 ?is case1 in/ead ( obta9+ ! acid z ! f9al product z we did above by heat+ ) wat] "u pressure1 we get ! sodium or potassium salt ( ! acid accord+ to ! alkali us$4 ,:5 cau/ic soda is us$1 ! product is a h>d soap2 :5 cau/ic pota% is us$1 x is a s(t soap4 ,! treatm5t ( fats 9 ?is way ) cau/ic alkalis is call$ 8saponification40 ,,*apt] ,,viii ,,mild ,,alkali ,cau/ic & ,mild4 ,!re are two classes ( alkalis di/+ui%$ by ! t]ms cau/ic & mild4 ,if a piece ( all-wool mat]ial is boil$ ) a solution ( cau/ic soda or pota%1 x dissolves completely1 giv+ a yell[ solution4 ,mild alkali w n dissolve flannel1 ?\gh x may h "s slight *emical action caus+ %r9kage4 ,p>tly = ?is reason1 & p>tly because comm]cial wa%+ soda (t5 conta9s a little cau/ic soda1 wooll5 g>m5ts mu/ n be boil$ or ev5 wa%$ 9 hot soda wat]4 ,! dis9tegrat+ action ( ! cau/ic alkalis is also illu/rat$ by ! use ( cau/ic soda 9 ! prep>ation ( wood pulp = pap] mak+4 ,tree trunks are fir/ torn up & %r$d$ by ma*9]y2 b not)/&+ ! p[] ( mod]n ma*9]y1 ! fibre is n ne>ly f9e en\gh = ! purpose until x has be5 8beat50 ) a solution ( cau/ic soda1 :]eby ! pulp is br\ght to a smoo? & uni=m consi/5cy l t ( ?9 cream4 ,mild ,soda & ,pota%4 ,until ! middle ( ! eighte5? c5tury1 x 0 ?\ght t ! soluble matt] extract$ f ! a%es ( all plants 0 ! same4 ,9 #ageb x 0 %[n t ! sub/ance obta9$ 9 ?is way f plants :i* grew 9 or ne> ! sea diff]$ f t f l& vegetation by produc+ a gold5 yell[ col\r :5 introduc$ into ! non-lum9\s flame ( a _s lamp1 :ile t f l& plants gave to ! flame a pale lilac t+e4 ,! =m] sub/ance is n[ kn[n z mild soda1 & ! latt] z mild pota%4 ,at ?is po9t x is well to make x cle> to ! read] t !re are two bodies commonly call$ soda1 & two call$ pota%4 ,"o ( ea* pair is cau/ic & "o mild4 ,by a simple *emical te/ x is easy to di/+ui% a mild f a cau/ic alkali4 ,:5 a little dilute acid is add$ to ! =m]1 !re is a vigor\s eff]vesc5ce caus$ by ! escape ( c>bon dioxide1 b no gas is giv5 (f :5 a cau/ic alkali is treat$ 9 ! same way4 ,! lib]ation ( c>bon dioxide on ! addition ( acids %[s t ! mild alkalis are c>bonates4 ,wa%+ ,soda is s well kn[n1 t v little description ( its ext]nal *>act]i/ics is necess>y4 ,x is a cry/all9e sub/ance1 easily soluble 9 wat]4 ,! cry/als1 :5 fre%ly prep>$1 are semi-transp>5t2 b aft] exposure to air = "s "t1 !y are f\nd to lose _! transp>5cy & to become coat$ ) an opaque :ite solid :i* crumbles easily4 ,?is *ange 9 appe>ance is accompani$ by a loss 9 weight4 ,cry/als ( soda melt v easily on ! application ( heat &1 on cont9u$ heat+1 ! liquid seems to boil4 ,:5 ?is op]ation is c>ri$ out 9 a vessel atta*$ to a cond5s]1 ! vap\r t is giv5 (f f ! melt$ soda cond5ses to a cle> col\rless liquid :i*1 on exam9ation1 proves to be wat]4 ,:5 no m wat] collects 9 ! receiv]1 ! vessel conta9s a dry1 :ite solid1 :i* by any *emical te/ t may be appli$ is %[n to be ! same z wa%+ soda1 b x conta9s no wat] ( cry/allization & has a diff]5t cry/all9e =m4 ,?is sub/ance is anhydr\s sodium c>bonate1 or soda a% z x is call$ 9 comm]ce4 ,:5 soda a% is mix$ ) wat]1 x comb9es ) ab\t twice its own weight ( t liquid1 =m+ soda cry/als aga94 ,wa%+ soda1 !n1 conta9s ne>ly two-?irds ( its weight ( wat]4 ,"s ( ?is wat] is giv5 (f spontane\sly :5 ! soda is expos$ to air2 ! wat] may ev5 be said to evaporate4 ,?is acc\nts = ! loss ( weight obs]v$ & also = ! =mation ( ! :ite lay] ( p>tially dehydrat$ soda ov] ! surface ( ! cry/al4 ,! prop]ty ( los+ wat] 9 ?is way is common to mo/ cry/als conta9+ a high p]c5tage ( wat] ( cry/allization4 ,! ph5om5on is kn[n z 8effloresc5ce40 ,x may "h be obs]v$ t cry/als ( wa%+ soda :i* h become coat$ ov] 9 ?is way conta9 relatively m soda ?an ^? :i* are transp>5t4 ,natural ,soda4 ,9 ,egypt1 ,?ibet1 & ,utah1 !re are tracts ( c\ntry :]e ! soil is s impregnat$ ) soda t ! l& is des]t4 ,! sep>ation ( ! soda f ! e>? is a simple op]ation1 = x is only necess>y to agitate ! soil ) wat] &1 aft] ! insoluble matt] has settl$ d[n1 to evaporate ! cle> solution until ! soda cry/allizes out4 ,9 addition to alkali des]ts1 !re are also alkali lakes4 ,^? 9 ,egypt are small1 nev]!less1 ab\t #cj1jjj tons ( soda p] annum are export$ f ,alex&ria4 ,ow5s ,lake 9 ,cali=nia is said to conta9 suffici5t soda to supply ! ne$s ( ,nor? ,am]ica2 :ile 9 ! ,ea/ ,african ,protectorate1 b5ea? ! %all[ wat]s ( ,lake ,magadi 7discov]$ 9 #aiaj71 !re is a deposit ( soda e/imat$ at #bjj1jjj1jjj tons4 ,! ,leblanc ,process4 ,at ! pres5t "t1 ! great] "p ( ! _w's supply ( soda is made f common salt by two processes4 ,! old] ( ^!1 :i* is kn[n z ! ,leblanc process1 0 introduc$ 9 ,france t[>ds ! end ( ! eighte5? c5tury4 ,9 ^? days soda 0 v de>1 = ! ma9 supply came f ! a%es ( seawe$s2 :]e=e ! ,fr5* ,academy ( ,sci5ces1 9 #agge1 (f]$ a prize = ! mo/ suitable me?od ( conv]t+ salt into soda on a manufactur+ scale4 ,! prize 0 won by ,ni*olas ,leblanc1 :o 9 #agia />t$ ! fir/ soda factory ne> ,p>is4 ,^! 7 ! days ( ! ,fr5* ,revolution2 ! 8,comit de ,sret ,gnral0 aboli%$ monopolies & ord]$ citiz5 ,leblanc to publi% ! details ( 8 process4 ,illu/ration3 ,fig4 #ab4 ,,salt ,,cake ,,furnace ,! fir/ alkali works 7 e/abli%$ 9 ,great ,brita9 9 #ahad4 ,! total am\nt ( soda n[ made 9 ?is c\ntry e ye> is ab\t #a1jjj1jjj tons1 ( :i* ne>ly "o-half is /ill made by ! ,leblanc process4 ,salt ,cake4 ,! fir/ /age ( ! ,leblanc process consi/s 9 mix+ a *>ge ( salt weigh+ "s hundr$weights ) ! requisite am\nt ( 8*amb]0 sulphuric acid4 ,! op]ation is c>ri$ out 9 a circul> ca/-iron pan 7,d1 ,fig4 #ab7 ab\t #i ft4 9 diamet] & #b ft4 deep4 ,! pan is cov]$ ov] ) a dome ( brickwork1 leav+ a c5tral flue 7,e7 = ! escape ( hydro*loric acid gas :i* is produc$4 ,at fir/1 ! reaction takes place )\t ! application ( heat1 b t[>ds ! end ! mass is heat$ = ab\t "o h\r4 ,! cont5ts ( ! pan are !n rak$ out on to ! he>? ( a rev]b]atory furnace 7a1 b7 & m /rongly heat$4 ,m hydro*loric acid gas is giv5 (f1 & ! reaction is complet$4 ,! solid product :i* rema9s is impure ,glaub]'s salt 7sodium sulphate71 & is kn[n 9 ! trade z 8salt cake40 ,black ,a%4 ,9 ! second /age ( ! ,leblanc process1 salt cake is conv]t$ into black a%4 ,! salt cake is cru%$ & mix$ ) an equal weight ( p[d]$ lime/one or *alk & half its weight ( coal du/4 ,?is mixture is introduc$ into a rev]b]atory furnace 7,fig4 #ac7 by ! hopp] ,k1 & heat$ to ab\t #ajjj ,c4 by flames & hot gases f a fire at a4 ,dur+ ?is op]ation1 ! mass is kept well mix$1 & aft] "s "t x is transf]r$ to h :]e ! temp]ature is high]4 ,! mixture !n becomes semi-fluid & c>bon monoxide gas is giv5 (f4 ,illu/ration3 ,fig4 #ac4 ,,black ,,a% ,,furnace ,! =mation ( c>bon monoxide )9 ! semi-solid mass r5d]s x por\s4 ,?is is an advantage1 because x greatly facilitates ! subsequ5t op]ation ( dissolv+ out ! soluble sodium c>bonate4 ,! appe>ance ( ! flames ( c>bon monoxide at ! surface ( ! black a% indicates ! end ( ! process4 ,! product is !n work$ up into balls & remov$ f ! furnace4 ,! *emical *anges :i* take place 9 mak+ black a% are probably z foll[s3 ,c>bon 7coal du/7 removes oxyg5 f sodium sulphate1 :i* is ?us *ang$ to sodium sulphide4 ,?is sub/ance !n reacts ) ! lime/one 7calcium c>bonate71 =m+ sodium c>bonate 7soda7 & calcium sulphide4 ,extraction ( ,soda4 ,x n[ only rema9s to dissolve out ! soda f ! insoluble impurities ) :i* x is mix$ 9 ! black a%4 ,x is evid5t t ! small] ! am\nt ( wat] us$ = ?is purpose ! bett]1 because ! wat] has subsequ5tly to be got rid ( by evaporation4 ,! process ( extraction is1 !re=e1 c>ri$ out sy/ematically4 ,! black a% is treat$ ) wat] 9 a s]ies ( tanks :i* are fitt$ ) p]=at$ false bottoms4 ,! soda solution1 :i* is heavi] ?an wat]1 t5ds to s9k to ! bottom &1 aft] pass+ ?r\gh ! p]=ations1 is c>ri$ away by a pipe to ! second tank1 & s on ?r\gh\t ! s]ies4 ,! fre% wat] is br\ght fir/ into contact ) ! black a% f :i* ne>ly all ! soda has be5 extract$4 ,! me?od ( f9i%+ (f ! black a% liquor diff]s accord+ to ! f9al product :i* ! manufactur] desires to obta91 = ! liquor conta9s cau/ic soda z well z mild soda4 ,= ! pres5t1 we w suppose t ! end product is to be wa%+ soda4 ,9 ?is case1 c>bon dioxide is pass$ into ! liquor to conv]t :at cau/ic soda !re is into mild soda4 ,! cl>ifi$ soda liquor is !n evaporat$ until cry/als ( soda sep>ate out4 ,! fir/ "p ( ?is process is c>ri$ out 9 l>ge %all[ pans 7,p4 ,fig4 #ac71 us+ ! wa/e heat ( ! black a% furnace1 & f9ally 9 vats conta9+ /eam-heat$ coils4 ,z ! cry/als sep>ate out1 !y are remov$1 dra9$1 & dri$4 ,alkali ,wa/e4 ,black a% conta9s less ?an half its weight ( soda1 s t = e ton ( soda produc$ !re is f a ton & a half to two tons ( an insoluble residue :i* collects 9 ! lixiviat+ & settl+ tanks4 ,?is residue is kn[n z alkali wa/e4 ,alkali wa/e is ( no p>ticul> value4 ,x is n ev5 suitable z a dress+ = ! l&1 & s9ce x is n soluble 9 wat] !re is no conv5i5t means ( dispos+ ( x4 ,consequ5tly1 x is j accumulat$ at ! works &1 z ! heap gr[s at an al>m+ rate1 x cumb]s mu* valuable gr\nd4 ,moreov]1 x conta9s sulphides f :i*1 "u ! influ5ce ( air & moi/ure1 sulphurett$ hydrog5 is lib]at$4 ,alkali wa/e1 !re=e1 has a v unpleasant od\r4 ,! :ole ( ! sulphur :i* 0 conta9$ 9 ! sulphuric acid us$ 9 ! fir/ /age ( ! process rema9s 9 ! alkali wa/e1 ma9ly z calcium sulphide4 ,a plant = ! recov]y ( ?is sulphur is e/abli%$ 9 "s ( ! l>g] works4 ,! alkali wa/e is mix$ ) wat] to ! consi/5cy ( a ?9 cream1 9 tall1 v]tical cyl9d]s4 ,c>bon dioxide "u pressure is =c$ into ! mixture1 & ?is conv]ts ! calcium sulphide into calcium c>bonate & sets free hydrog5 sulphide1 :i*1 :5 burnt ) a limit$ supply ( air1 yields sulphur4 ,by ?is process1 ! mo/ unpleasant feature ( alkali wa/e1 namely1 ! smell1 is remov$4 ,! calcium c>bonate :i* rema9s is ( v little value4 ,"s ( x is us$ 9 mak+ up fre% *>ges = ! black a% process & "s = prep>+ ,portl& cem5t1 = :i* f9ely-gr\nd calcium c>bonate is requir$2 ! rema9d] is ?r[n on a heap4 ,bic>bonate ( ,soda4 ,bic>bonate ( soda c be easily di/+ui%$ f wa%+ soda4 ,x is a f9e1 :ite p[d] simil> 9 appe>ance to ! effloresc5ce on soda cry/als4 ,x does n conta9 any wat] ( cry/allization4 ,:5 bic>bonate ( soda is heat$1 x does n melt1 &1 z f> z its ext]nal appe>ance is conc]n$1 x does n seem to und]go any *ange4 ,if1 h[ev]1 suitable arrangem5ts are made1 wat] & c>bon dioxide gas c be collect$1 & ! sodium bic>bonate w be f\nd to h lo/ #cfi p] c5t4 ( its weight4 ,! sub/ance :i* rema9s is id5tical ) t obta9$ by heat+ soda cry/als1 t is1 anhydr\s sodium c>bonate4 ,sodium bic>bonate is1 !re=e1 a comp\nd ( sodium c>bonate & c>bonic acid4 ,! mo/ famili> use ( ?is comp\nd is indicat$ by its common names 8bak+-soda0 & 8bread-soda40 ,x is mix$ ) d\gh or o!r simil> mat]ial 9 ord] to keep ?is f settl+ d[n to a h>d solid mass 9 bak+4 ,! way 9 :i* bic>bonate ( soda prev5ts ?is w be readily und]/ood :5 x is rememb]$ t an ounce ( ?is sub/ance lib]ates m ?an #b1cjj cu4 94 ( c>bon dioxide :5 x is heat$4 ,:5 ! bic>bonate ( soda is well mix$ ) ! +r$i5ts ( ! cake or loaf & dissem9at$ ?r\gh\t ! mass1 ea* p>ticle w furni% 7let u say7 its bubble ( gas4 ,s9ce ^! _c escape1 a honey-comb$ /ructure is produc$4 ,illu/ration3 ,fig4 #ad4 ,,! ,,solvay ,,process ,bak+ p[d] is a mixture ( bic>bonate ( soda & gr\nd rice2 ! latt] sub/ance is m]ely a solid dilu5t4 ,! ,solvay ,process4 ,soda a% is "o ( ! pr9cipal =ms ( mild alkali us$ 9 comm]ce4 ,l>ge quantities ( ?is sub/ance are made by heat+ bic>bonate ( soda4 ,we %all n[ consid] ano!r alkali process 9 :i* ?is sub/ance is ! prim>y product4 ,= ! great] "p ( ! fir/ c5tury ( its exi/5ce1 ! ,leblanc soda process _h no rival1 al?\gh ano!r me?od1 kn[n z ! ammonia-soda process1 0 pat5t$ z e>ly z #ahch4 ,9 ?is case1 h[ev]1 z 9 _m o!rs1 expectations bas$ on ! exp]im5ts c>ri$ out 9 ! laboratory 7 n realiz$ :5 ! me?od came to be tri$ "u manufactur+ conditions4 ,x 0 n until #ahgb t ,erne/ ,solvay1 a ,belgian *emi/1 _h s f> solv$ ! difficulties1 t a new />t c\ld be made4 ,9 t ye>1 ab\t #c1jjj tons ( soda 7 produc$ by ! ammonia-soda or ,solvay process1 z x has n[ come to be kn[n4 ,s9ce !n1 h[ev]1 ! quantity produc$ annually has be5 /eadily increas+1 until at ! pres5t "t x am\nts to m ?an half ( ! _w's supply4 ,! ,solvay process is v simple 9 !ory4 ,purifi$ br9e is saturat$ fir/ ) ammonia gas & !n ) c>bon dioxide4 ,wat]1 ammonia1 & c>bon dioxide comb9e1 =m+ ammonium bic>bonate1 :i* reacts ) salt 7sodium *loride71 produc+ sodium bic>bonate & ammonium *loride4 ,! pr9cipal reaction is c>ri$ out 9 a t[] 7,fig4 #ad 7#a71 a1 a7 f #ej to #fe ft4 9 height & ab\t #f ft4 9 diamet]4 ,at int]vals ( ab\t #c ft4 ?r\gh\t its l5g?1 ! t[] is divid$ into sections by pairs ( transv]se discs1 "o flat ) a l>ge c5tral hole1 & "o hemisph]ical & p]=at$ ) small holes 7,fig4 #ad 7#b774 ,! discs are kept 9 position by a guide rod ,g4 ,fig4 #ad 7#c7 %[s a bett] arrangem5t ( ! guide rods4 ,9 mod]n works1 ! space betwe5 ! discs is kept cool by pipes convey+ runn+ wat]4 ,! ammoniat$ br9e is l$ into ! t[] ne> its middle po9t4 ,! c>bon dioxide is =c$ 9 at ,e 9 ! l[e/ segm5t1 & z x passes up ! t[] x is brok5 up into small bubbles by ! sieve plates4 ,sodium bic>bonate sep>ates out z a f9e p[d]1 :i* makes its way to ! bottom ( ! t[] susp5d$ 9 ! liquid4 ,! p]=at$ plates are necess>y = ! prop] di/ribution ( c>bon dioxide ?r\gh ! br9e4 ,!y are1 h[ev]1 a s\rce ( tr\ble1 because ! holes quickly become block$ up ) sodium bic>bonate1 & e t5 days or s x is necess>y to empty ! t[] & clean x out ) /eam or boil+ wat]4 ,recov]y ( ,ammonia4 ,! production ( #a ton ( soda a% by ! ,solvay process involves ! use ( a quantity ( ammonia :i* co/s ab\t eight times z mu* z ! price realiz$ by sell+ ! soda4 ,x is evid5t t ! success ( ! process z a comm]cial v5ture dep5ds l>gely on ! complet5ess ) :i* ! ammonia c be recov]$4 ,dur+ ! process1 ammonia is conv]t$ into ammonium *loride1 :i* rema9s dissolv$ 9 ! residual liquor4 ,f ?is ammonia gas is set free by add+ quicklime & by bl[+ /eam ?r\gh ! mixture4 ,x is n[ claim$ t #ii p] c5t4 ( ! ammonia us$ 9 "o op]ation is recov]$4 ,soda ,a%4 ,! bic>bonate ( soda produc$ by ! ,solvay process is mod]ately pure4 ,= all ord9>y purposes1 x is only necess>y to wa% x ) cold wat] to remove un*ang$ salt1 & aft] dry+1 x is ready to be plac$ on ! m>ket if x is to be sold z bic>bonate4 ,! great] "p ( ! ,solvay product1 h[ev]1 is conv]t$ into soda a% by ! application ( heat4 ,if soda cry/als are requir$1 ! soda a% is dissolv$ 9 wat] & cry/alliz$4 ,9 _m ways1 ! ,solvay process comp>es v fav\rably ) ! old] me?od4 ,x is an advantage to />t ) br9e1 = t is ! =m 9 :i* salt is v (t5 rais$ f ! m9es4 ,! end product is relatively pure2 moreov]1 x is q free f cau/ic soda1 :i* = "s purposes = :i* soda a% is us$ is a great recomm5dation4 ,!re is no unpleasant smell+ alkali wa/e4 ,on ! o!r h&1 ! effici5cy ( ! ,solvay process is n high1 = only ab\t "o-?ird ( ! salt us$ is conv]t$ into soda4 ,?is w\ld make ! process impossible f ! comm]cial po9t ( view 7 x n = ! *eapness ( salt4 ,! ,leblanc process1 too1 has its advantages4 ,9 ! next *apt] we %all see t x is adaptable = ! production ( cau/ic z well z mild alkali4 ,! *lor9e :i* is recov]$ 9 ! ,leblanc process is a v valuable by-product4 ,9 ! ,solvay process1 *lor9e is lo/1 = hi!rto no practicable me?od has be5 f\nd = its recov]y f calcium *loride4 ,! position ) reg>d to ! future supply ( alkali is v int]e/+4 ,! competition betwe5 ! ,leblanc & ! ,solvay processes = supremacy 9 ! m>ket is v ke54 ,at ! same "t1 bo? processes are 9 "s degree ( dang] ( be+ supplant$ by ! new] electrical me?ods1 :i* w be m5tion$ 9 ! la/ *apt]4 ,! foll[+ table %[s v cle>ly ! rapid progress made by ! ,solvay process 9 t5 ye>s4 ,! quantities are giv5 9 tonnes 7#a tonne #jihdb ton74 #ahhd4 #ahid4 ,leblanc ,solvay ,leblanc ,solvay soda4 soda4 soda4 soda4 ,great ,brita9 #chj1jjj #eb1jjj #cdj1jjj #aha1jjj ,g]many #ef1ejj #dd1jjj #dj1jjj #baj1jjj ,france #gj1jjj #eg1jjj #bj1jjj #aej1jjj ,unit$ ,/ates -- #a1ajj #bj1jjj #hj1jjj ,au/ria-,hung>y #ci1jjj #a1jjj #bj1jjj #ge1jjj ,russia -- -- #aj1jjj #ej1jjj ,belgium -- #h1jjj #f1jjj #cj1jjj #ede1ejj #afc1ajj #def1jjj #ggf1jjj ,mild ,pota%4 ,potassium c>bonate 7mild pota%7 0 =m]ly obta9$ f wood a%es4 ,! cle> aque\s extract 0 evaporat$ to dryness 9 iron pots1 & ! sub/ance 0 on ?is acc\nt call$ pota%es2 lat]1 pota%4 ,a :it] product 0 obta9$ by calc9+ ! residue1 & ?is 0 di/+ui%$ z pe>l-a%4 ,*emically pure potassium c>bonate 0 =m]ly obta9$ by ignit+ cream ( t>t> 7potassium hydrog5 t>trate7 ) an equal weight ( nitre4 ,x is = ?is reason t potassium c>bonate is sometimes call$ 8salt ( t>t>40 ,ab\t ! middle ( la/ c5tury1 natural deposits ( potassium *loride 7 discov]$ 9 ,g]many4 ,! b$s ( rock salt ne> ,/assfurt are cov]$ ov] ) a lay] ( o!r salts1 & = _m ye>s ^! 7 remov$ & ca/ aside z 8wa/e salts0 7abraumsalze74 ,:5 at a lat] date !y 7 exam9$ m c>efully1 !y 7 f\nd to conta9 valuable potassium comp\nds1 notably ! *loride4 ,aft] t discov]y1 mild pota% 0 made by ! ,leblanc process41 & ,g]many controll$ ! _w's m>kets = all potassium comp\nds4 ,at ! outbreak ( w>1 ! ,g]man supplies ( potassium comp\nds ceas$ z f> z ! alli$ nations 7 conc]n$1 & an old] me?od ( mak+ potassium *loride f or?oclase or pota%-felsp> 0 reviv$4 ,?is involves ! heat+ ( ! p[d]$ m9]al to a high temp]ature aft] mix+ x ) calcium *loride1 lime1 & a little fluorsp>4 ,! potassium *loride is !n extract$ f ! fus$ mass ) wat]4 ,?is me?od has be5 work$ ) great success 9 ,am]ica1 & x is claim$ t potassium *loride c be made 9 t c\ntry at a co/ :i* is l[] ?an t =m]ly paid = ! import$ article4 ,mild pota% & soda are s v simil> 9 *emical prop]ties t 9 mo/ cases x is immat]ial :i* comp\nd is us$4 ,9 all cases 9 :i* !re is ?is *oice1 soda is employ$1 bo? because x is *eap] & because x is m economical1 = #ajf p>ts ( soda a% are equival5t to #ach p>ts ( pota%4 ,!re are1 h[ev]1 "s occasions :5 soda _c be sub/itut$1 notably = ! manufacture ( h>d glass & s(t soap1 & = ! prep>ation ( cau/ic pota%1 potassium di*romate1 & o!r potassium salts4 ,potassium ,bic>bonate4 ,?is resembles ! correspond+ sodium salt 9 ne>ly e respect4 ,x is1 h[ev]1 mu* m readily soluble 9 wat]1 s mu* s1 t x is n possible to obta9 ?is sub/ance by ! ,solvay me?od4 ,x is made f potassium c>bonate by saturat+ a /rong aque\s solution ( t sub/ance ) c>bon dioxide4 ,,*apt] ,,ix ,,cau/ic ,,alkalis ,! ,alkali ,metals4 ,! discov]y ( curr5t electricity 9 #agij furni%$ ! *emi/ ) a v p[]ful ag5cy = br++ ab\t ! decomposition ( comp\nds4 ,hydrog5 & oxyg5 7 soon obta9$ by pass+ an electric curr5t ?r\gh acidulat$ wat]2 & 9 #ahjg1 ,sir ,humphry ,davy1 :o is p]haps bett] rememb]$ = 8 inv5tion ( ! m9]s' lamp1 isolat$ ! metals sodium & potassium by subject+ cau/ic soda & cau/ic pota% respectively to ! action ( ! curr5t4 ,sodium & potassium are v rem>kable metals4 ,!y are only a little h>d] ?an putty1 & c easily be cut ) a knife or m\ld$ betwe5 ! f+]s4 ,:5 expos$ to ! air1 !y ru/ or oxidize v rapidly1 s mu* s t !y h to be pres]v$ 9 "s m9]al oil or 9 airtight t9s4 ,!y are light] ?an wat]1 :i* !y decompose ) ! lib]ation ( hydrog51 & "u fav\rable circum/ances ! hydrog5 takes fire s t ! metals appe> to burn on ! surface ( ! wat]4 ,aft] ! reaction is ov] & ! sodium or potassium has disappe>$1 a cle> col\rless liquid rema9s :i* has a /rongly alkal9e reaction1 & :5 ?is is evaporat$ until ! residue solidifies on cool+1 cau/ic soda or pota% is obta9$4 ,= v special purposes1 ! cau/ic alkalis are sometimes made by ! action ( ! metals on wat]1 b = production on a l>ge scale1 less exp5sive me?ods are adopt$4 ,cau/ic ,alkali is obta9$ f ! correspond+ mild alkali 9 ! foll[+ way4 ,! sub/ance--wa%+ soda1 = example--is dissolv$ 9 wat] & ! solution is w>m$4 ,lime is /irr$ into ?is solution1 & f "t to "t a small te/ portion ( ! cle> sup]natant liquid is remov$ & mix$ ) a dilute m9]al acid4 ,:5 ?is ceases to cause eff]vesc5ce1 ! *ange is complete4 ,! cle> liquid is n[ sep>at$ f ! solid matt] 7excess ( lime toge!r ) calcium c>bonate7 & evaporat$ 9 a metal di%4 ,s9ce ! cau/ic alkalis are extremely soluble 9 wat]1 !y d n cry/allize z d mo/ ( ! comp\nds previ\sly describ$4 ,evaporation is1 !re=e1 c>ri$ on until ! liquid :i* rema9s solidifies :5 cold4 ,cau/ic ,soda4 ,to describe ! process by :i* cau/ic soda is manufactur$1 we mu/ return to ! mak+ ( black a%4 ,! mixture f :i* black a% is made conta9s lime/one4 ,x is heat$ to #ajjj ,c41 :i* is a suffici5tly high temp]ature to conv]t lime/one into lime4 ,:5 ! black a% is subsequ5tly treat$ ) wat]1 ! lime :i* is pres5t conv]ts "s ( ! mild alkali to cau/ic2 consequ5tly1 black a% liquor always conta9s bo? alkalis4 ,:5 ! manufactur] int5ds to make cau/ic soda & n soda cry/als1 ! composition ( ! black a% mixture is v>i$ by add+ a l>g] proportion ( lime/one1 s t !re may be an excess ( lime 9 ! black a% produc$4 ,! treatm5t ) wat] is c>ri$ out z describ$ "u wa%+ soda1 & !n m lime is add$ to conv]t ! mild soda into cau/ic soda4 ,aft] ! excess ( lime & o!r susp5d$ matt] has settl$ d[n1 ! cle> cau/ic liquor is evaporat$ 9 iron kettles until x becomes molt5 cau/ic1 :i* w solidify on be+ all[$ to cool4 ,!re are v>i\s grades ( cau/ic soda on ! m>ket diff]+ "o f ano!r 9 purity4 ,! soap manufactur] uses cau/ic liquor or lye conta9+ ab\t #dj p] c5t4 ( cau/ic soda4 ,= o!r purposes1 ! solid conta9+ f #fj to #gh p] c5t4 is us$4 ,sometimes ! product is :it5$ by bl[+ air ?r\gh ! /rong cau/ic liquor or by ! addition ( a little potassium nitrate4 ,f9ally1 = analytical purposes1 cau/ic soda is purifi$ by dissolv+ x 9 alcohol & subsequ5tly evaporat+ ! cle> liquid4 ,cau/ic ,pota%4 ,! me?ods = ! prep>ation ( ! correspond+ potassium comp\nd are precisely ! same z ^? describ$ = cau/ic soda2 9 fact1 :]ev] ! words sodium & soda occur 9 ?is *apt]1 ! read] c always sub/itute potassium & pota% respectively4 ,cau/ic ,lime4 ,ap>t f its use 9 mak+ mort> & cem5t1 lime is v (t5 employ$ to neutralize acids4 ,= ?is purpose1 a susp5sion 9 wat]1 call$ milk ( lime1 is g5]ally us$1 = lime itself is n v soluble4 ,probably x is only ! soluble "p :i* reacts2 nev]!less1 z soon z ?is is us$ up1 m ( ! solid dissolves1 & 9 ?is way ! action goes on z if all ! lime 7 9 solution4 ,lime is also a v valuable sub/ance 9 agriculture1 especially on damp1 boggy l&1 :]e !re is mu* decay+ vegetable matt]1 & on l& :i* has be5 lib]ally manur$4 ,! soil 9 ^! cases is v likely to become acid & is !n unproductive4 ,lime is add$ to 8sweet50 ! soil2 9 o!r words1 to neutralize ! acid4 ,ammonia4 ,! pung5t smell+ liquid popul>ly kn[n z 8spirits ( h>t%orn0 is a solution ( ammonia gas 9 wat]4 ,x is a cau/ic alkali &1 z su*1 is sometimes us$ to remove grease spots4 ,"h1 h[ev]1 we %all consid] ammonia only 9 connection ) ammonium salts1 "s ( :i* are us$ 9 v l>ge quantity z f]tiliz]s4 ,! pr9cipal s\rce ( ammonia at ! pres5t "t is ! ammoniacal liquor obta9$ z a by-product 9 ! manufacture ( gas = heat+ & light+4 ,coal conta9s ab\t #a p] c5t4 ( nitrog51 & :5 x is di/ill$1 "s ( ?is nitrog5 is giv5 (f z ammonia1 :i* dissolves 9 ! wat] produc$ at ! same "t4 ,?is liquid is cond5s$ 9 ! hydraulic ma9 & 9 o!r p>ts ( ! plant :]e ! gas is cool$ d[n4 ,gas liquor conta9s *iefly ! c>bonate1 sulphide1 sulpho-cyanide1 & *loride ( ammonia1 toge!r ) _m o!r sub/ances1 "s ( :i* are ( a t>ry nature4 ,x w\ld n be practicable to evaporate ?is liquid ) a view to obta9+ ! ammonium salts1 because x is only a v dilute solution4 ,h5ce1 aft] ! removal ( t>1 ! liquor is treat$ 9 su* a way t ammonia is set free4 ,9 "s cases ! lib]ation ( ammonia is accompli%$ by bl[+ sup]heat$ /eam into ! liquor1 :i* sets free ! ammonia :i* is comb9$ z c>bonate1 sulphide1 & sulpho-cyanide1 b n t :i* is pres5t z *loride4 ,9 o!r works1 ! gas liquor is mix$ ) milk ( lime1 :i* lib]ates all ! comb9$ ammonia4 ,! ammonia is !n expell$ f ! mixture by a curr5t ( /eam or air & /eam4 ,9 bo? cases1 ! gas :i* is giv5 (f is pass$ into sulphuric acid1 :]eby ammonium sulphate is =m$ 9 solution & aft]w>ds obta9$ z a solid by evaporation4 ,ammonium ,salts ,ammonium ,*loride4 ,l all o!r alkalis1 ammonia solution neutralizes acids1 =m+ salts4 ,) hydro*loric acid1 x produces ! :ite solid kn[n z sal ammoniac or ammonium *loride4 ,?is comp\nd is famili> z ! "o requir$ to make ! liquid us$ 9 a ,leclan* cell1 :i* is g5]ally us$ z ! curr5t g5]ator = electric bells4 ,ammonium ,c>bonate1 :i* is also call$ /one ammonia & salt ( h>t%orn1 is made by sublim+ a mixture conta9+ two p>ts *alk & "o "p ammonium sulphate4 ,x is a :ite solid :i* gives (f ammonia sl[ly & is1 !re=e1 us$ z ! basis = smell+ salts4 ,ammonium ,nitrate is obta9$ by pass+ ammonia gas into nitric acid until x is neutraliz$4 ,x is a :ite solid1 :i* melts easily on be+ heat$1 & breaks up into wat] & nitr\s oxide 7laugh+ gas71 :i* is ! 8gas0 adm9i/]$ by d5ti/s4 ,ammonium nitrate is also us$ 9 ! composition ( "s explosives3 = example1 8ammonite0 is said to conta9 #hj p] c5t4 ( ?is sub/ance4 ,ammonium ,sulphate is us$ *iefly z an artificial manure2 ! am\nt requir$ = ?is purpose ?r\gh\t ! _w is ov] #a1ejj1jjj tons e ye>4 ,syn!tic ,ammonia4 ,?\gh ! soluble comp\nds ( nitrog5 are fairly abundant1 ! supply is by no means equal to ! dem&1 because su* enorm\s quantities are requir$ = agricultural purposes4 ,x has be5 already said t ammonia is obta9$ z a by-product 9 ! di/illation ( coal1 & x has be5 repeat$ly po9t$ out t our coal supplies are f> f inexhau/ible2 moreov]1 coal gas may n always be us$ = light+ & heat+4 ,x1 !re=e1 becomes a v important "q z to h[ ! future supply ( ammonium salts is to be ma9ta9$4 ,ammonia is a v simple comp\nd =m$ f ! elem5ts nitrog5 & hydrog51 &1 z be=e m5tion$1 ! supply ( free nitrog5 9 ! air is lit]ally inexhau/ible4 ,9 rec5t ye>s1 ! ef=ts ( *emi/s h be5 direct$ t[>ds f9d+ a me?od ( conv]t+ ! free nitrog5 ( ! air into "s simple soluble comp\nd4 ,?is problem is usually spok5 ( z ! 8fixation ( nitrog540 ,9 ! ,hab] process1 nitrog5 obta9$ by ! fractional di/illation ( liquid air is mix$ ) ?ree times its volume ( hydrog51 & ?is mixture is heat$ to betwe5 #ejj;,c4 & #gjj;,c4 "u a pressure ( #aej atmosph]es 7ne>ly #a ton to ! squ>e in*7 & 9 ! pres5ce ( a contact ag5t4 ,"u ^! conditions1 nitrog5 & hydrog5 comb9e to =m ammonia1 :i* is cond5s$ by pass+ ! mix$ gases into a vessel cool$ ) liquid air1 any un*ang$ nitrog5 & hydrog5 be+ pass$ back aga9 ov] ! contact sub/ance4 ,! problem ( mak+ ammonia f ! air is closely connect$ ) t ( mak+ nitric acid f ! same s\rce4 ,9 "s exp]im5ts ! two are comb9$1 & ammonium nitrate is produc$ directly4 ,ammonia made by ! ,hab] process1 or "s modification1 is mix$ ) atmosph]ic oxyg5 & pass$ ?r\gh plat9um gauze heat$ to l[ r$ness4 ,?is results 9 ! =mation ( nitric oxide1 :i* is fur!r oxidiz$ by atmosph]ic oxyg52 & f9ally1 f a mixture ( oxides ( nitrog51 wat] vap\r1 & ammonia1 syn!tic ammonium nitrate is obta9$4 ,,*apt] ,x ,,electrolytic ,,me?ods ,"o ( ! mo/ notewor?y developm5ts ( mod]n *emical indu/ry has be5 ! increas+ use ( electricity z an ag5t = br++ ab\t *anges 9 matt]4 ,?is has foll[$ naturally f ! r$uction 9 ! co/ ( electricity1 due 9 great measure to ! utilization ( natural s\rces ( en]gy :i* = untold ages _h be5 all[$ to run to wa/e4 ,?is la/ a*ievem5t is likely to produce su* a *ange 9 economic conditions t x is wor? :ile giv+ a little ?\ght to :at may be call$ a newly-discov]$ asset ( civilization4 ,"o example w make ?is cle>4 ,9 ! b$ ( ! ,niag>a riv]1 :i* fl[s f ,lake ,erie to ,lake ,ont>io1 !re is a sudd5 drop ( #afg ft4 ov] :i* ! wat] ru%es ) trem5d\s =ce & exp5ds its en]gy 9 produc+ heat :i* _c be utiliz$4 ,?is is a wa/e ( en]gy1 b x _c be circumv5t$ because no me?od has yet be5 f\nd to control ! wat]s ( ! ,falls !mselves4 ,nev]!less1 by lead+ ! head wat]s ?r\gh suitable *annels f ! high level to ! l[1 x is possible to use ! en]gy to drive turb9es1 :i*1 9 _! turn1 drive dynamos :i* produce ! curr5t4 ,?is is m]ely ! conv]sion ( ! en]gy ( runn+ wat] into electrical en]gy2 & :ile ! sun rema9s1 ?is supply ( en]gy w be =?com+ 9 undim9i%$ quantity1 because by ! heat ( ! sun ! wat] is lift$ aga9 z vap\r1 :i* desc5ds z ra9 to repl5i% ! s\rces f :i* ! ,niag>a fl[s4 ,electricity is employ$ 9 *emical indu/ry 9 two ways4 ,9 ! fir/ place1 x may be us$ to produce v high temp]atures requir$ = ! r$uction ( "s metallic ores1 = melt+ highly-refractory sub/ances1 & = mak+ /eel4 ,x is1 h[ev]1 r ) ! second me?od1 call$ electrolysis1 t we are "h ma9ly conc]n$4 ,illu/ration3 ,fig4 #ae4 ,,! ,,electrolysis ,,( ,,salt ,,solution ,solutions ( acids1 bases1 & salts1 & 9 "s cases ! fus$ sub/ances !mselves1 conduct ! electric curr5t2 b at ! same "t !y suff] decomposition4 ,?is me?od ( decompos+ a sub/ance is kn[n z electrolysis1 or a break+ up by ! ag5cy ( electricity4 ,! app>atus requir$ 9 a v simple case is %[n 9 ,fig4 #ae4 ,x m]ely consi/s ( "s suitable vessel to conta9 ! liquid2 two plates--"o to lead ! curr5t into ! solution1 ! o!r to lead x away aga9--& wires to connect ! plates to ! poles ( a batt]y1 /orage-cell1 or dynamo4 ,ea* plate is call$ an electrode1 & di/+ui%$ z positive or negative accord+ z x is jo9$ to ! positive or negative pole ( ! curr5t g5]ator4 ,by conv5tion1 electricity is suppos$ to 8fl[0 f ! positive pole ( ! batt]y to ! positive electrode or anode1 & !n ?r\gh ! solution to ! negative electrode or ca?ode1 & s back to ! negative pole ( ! g5]ator1 ?us complet+ ! circuit ext]nal to ! batt]y4 ,:5 acids1 alkalis1 & salts are dissolv$ 9 wat]1 !re is /rong evid5ce to %[ t !y break up to a great] or less ext5t into at lea/ two p>ts call$ ions4 ,^! are atoms1 or gr\ps ( atoms1 :i* h ei!r acquir$ or lo/ "o or m electrons4#e ,!y move ab\t q indep5d5tly ( "o ano!r & 9 any direction until ! electrodes are plac$ 9 ! liquid4 ,!n !y are con/ra9$ to move 9 two oppos+ /reams--^? :i* h acquir$ electrons all move t[>ds ! negative electrode1 & ^? :i* h lo/ electrons t[>ds ! o!r4 ,at ! electrodes !mselves1 ! =m] give up & ! latt] take up electrons1 & become atoms aga94 ,let u n[ consid] a concrete example4 ,common salt is compos$ ( atoms ( sodium & atoms ( *lor9e pair$4 ,:5 a small quantity ( ?is sub/ance is dissolv$ 9 a l>ge quantity ( wat]1 ! pair+ no long] obta9s4 ,! *lor9e atoms move away indep5d5tly accompani$ by an extra satellite or electron1 & ! sodium atoms move away also b ) _! electron /r5g? "o bel[ p>4 ,:5 ! curr5t is introduc$ into ! liquid1 ! sodium ions travel t[>ds ! ca?ode & *lor9e ions t[>ds ! anode1 & :5 !y rea* ! goal1 sodium ions ga9 "o electron & *lor9e ions lose "o1 & bo? become atoms aga94 ,*lor9e atoms comb9e 9 pairs =m+ molecules & escape f ! solution 9 ! gre5i% yell[ cl\d t we call *lor9e gas4 ,! sodium atoms react imm$iately ) wat]1 =m+ cau/ic soda ) ! lib]ation ( hydrog54 ,to return n[ to practical consid]ations4 ,! electrolysis ( salt solution appe>s to be an ideally simple me?od ( obta9+ cau/ic soda & *lor9e f sodium *loride4 ,z a manufactur+ process1 x w\ld seem to be p]fect1 = ! salt is brok5 up directly into its elem5ts & a second>y reaction gives cau/ic soda automatically4 ,!re is no 8wa/e0 z 9 ! ,leblanc process1 & x does n require ! use ( any exp5sive int]m$i>y sub/ance aft]w>ds to be recov]$1 z 9 ! ,solvay process4 ,b1 z v (t5 happ5s :5 work+ on a l>ge scale1 difficulties arise1 & ^! up to ! pres5t h only be5 p>tially ov]come4 ,"s ( ! *lor9e rema9s dissolv$ 9 ! liquid & reacts ) ! cau/ic soda1 =m+ o!r sub/ances :i*1 ?\gh valuable1 are n easy to sep>ate f ! cau/ic soda4 ,x is possible to get ov] ?is difficulty to "s ext5t by plac+ a por\s p>tition betwe5 ! anode & ! ca?ode1 & 9 t way divid+ ! cell into ca?odic & anodic comp>tm5ts4 ,z long z ! p>tition is por\s to liquids1 x w all[ ! curr5t to pass1 b at ! same "t x w greatly ret>d ! mix+ ( ! cont5ts ( ! two comp>tm5ts4 ,por\s p>titions or cells :i* are 9 common use = batt]ies are made ( 8biscuit0 or unglaz$ porcela94 ,x mu/ be rememb]$1 h[ev]1 t por\s p>titions only ret>d ! mix+ ( liquids2 !y d n prev5t x4 ,moreov]1 a fur!r difficulty arises f ! fact t *lor9e is a mo/ active sub/ance1 & !re=e x is difficult to f9d a mat]ial :i* w resi/ its corrosive action = any l5g? ( "t1 & ! same difficulty arises 9 ! case ( ! anode :]e ! *lor9e is giv5 (f4 ,ca/n] ,process = ,cau/ic ,soda4 ,! foll[+ is ! mo/ successful electrical process = ! manufacture ( cau/ic soda yet devis$4 ,x 0 introduc$ 9 #ahib1 & is kn[n z ! ,ca/n] process4 ,x %\ld be not$ t ! use ( ! por\s p>tition has be5 avoid$ 9 a v +5i\s way4 ,illu/ration3 ,fig4 #af4 ,,! ,,ca/n] ,,process ,! cell 7see ,fig4 #af7 is a clos$1 rectangul>-%ap$ tank divid$ into ?ree comp>tm5ts by two non-por\s p>titions fix$ at "o end to ! top ( ! tank1 :ile ! o!r end is free & fits loosely into a *annel runn+ across ! tank4 ,! floor ( ! tank is cov]$ ) a lay] ( m]cury ( suffici5t dep? to seal ! sep>ate comp>tm5ts4 ,! two end comp>tm5ts conta9 ! br9e 9 :i* are ! c>bon anodes2 ! middle comp>tm5t conta9s wat] or v dilute cau/ic soda 9 :i* ! ca/-iron ca?ode is imm]s$4 ,! curr5t ent]s ! end comp>tm5ts by ! c>bon anodes & passes ?r\gh ! salt solution to ! m]cury lay] :i* 9 ^! comp>tm5ts are ! ca?odes4 ,! curr5t !n passes ?r\gh ! m]cury to ! middle comp>tm5t1 & !n ?r\gh ! solution to ! ca?ode1 !nce back to ! dynamo4 ,x is important to note t 9 ! middle comp>tm5t ! m]cury becomes ! anode4 ,*lor9e is lib]at$ at ! c>bon electrodes1 & :5 no m c dissolve 9 ! liquid x escapes & is convey$ away by ! pipe ,p4 ,sodium atoms are =m$ at ! surface ( ! m]cury ca?odes 9 ! outside comp>tm5ts & dissolve in/antly 9 ! m]cury1 =m+ sodium amalgam4 ,:ile ! curr5t is pass+1 a slight rock+ motion is giv5 to ! tank by ! cam ,e4 ,?is is suffici5t to cause ! m]cury conta9+ ! dissolv$ sodium to fl[ alt]nately into ! middle comp>tm5t1 & !re ! sodium amalgam comes into contact ) wat]2 ! sodium is dissolv$ out ( ! m]cury & cau/ic soda is =m$4 ,wat] 9 a regulat$ /ream is con/antly admitt$ to ! middle comp>tm5t1 & a solution ( cau/ic soda ( ab\t #bj p] c5t4 /r5g? ov]fl[s4 ,! production ( cau/ic soda by an electrical me?od /ill rema9s to be fully develop$4 ,a process :i* gives only a #bj p] c5t4 solution _c be look$ ^u z f9al4 ,9 ! meantime1 o!r me?ods h be5 tri$1 9 "s ( :i* fus$ salt is us$ 9 place ( br9e 9 ord] to give cau/ic soda 9 a m conc5trat$ =m4 ,= a description ( ^! me?ods1 ! read] mu/ consult "s ( ! l>g] works m5tion$ 9 ! preface4 ,"h we c only say t v great difficulties h be5 enc\nt]$1 p>ticul>ly 9 ! con/ruction ( a satisfactory por\s diaphragm or1 alt]nately1 9 devis+ me?ods 9 :i* ?is c be disp5s$ )4 ,ano!r int]e/+ application ( electrolysis is furni%$ by ! use ( copp] sulphate 9 indu/ry4 ,:5 ?is salt is dissolv$ 9 wat]1 x breaks up into copp] ions 7positive7 & an equal numb] ( negative ions1 compos$ ( #a atom ( sulphur & #d atoms ( oxyg5 7,,s#d74 ,"u ! influ5ce ( ! curr5t copp] ions travel to ! ca?ode1 & !re by ! ga9 ( two electrons become copp] atoms4 ,n[1 s9ce copp] is n soluble 9 copp] sulphate solution1 & is n volatile except at v high temp]atures1 x is deposit$ on ! ca?ode 9 a p]fectly ev5 & cont9u\s film :5 ! /r5g? ( ! curr5t is suitably adju/$4 ,?is film cont9ues to gr[ 9 ?ickness z long z ! conditions = its deposition are ma9ta9$4 ,if ! curr5t employ$ is n suitable1 ! metallic film is n coh]5t1 & ! copp] may appe> z a r$ p[d] at ! bottom ( ! cell4 ,any o!r metal or impurity :i* might be pres5t 9 ! unref9$ copp] falls to ! bottom ( ! tank4 ,o!r metals are deposit$ electrolytically 9 exactly ! same way4 ,! metal to be deposit$ is jo9$ to ! positive pole & ! article to be plat$ to ! negative pole ( ! batt]y4 ,bo? are susp5d$ 9 a solution ( salt1 g5]ally ! sulphate1 ( ! metal :i* is to be deposit$4 ,?us1 = nickel plat+1 a piece ( %eet nickel w\ld be us$ 9 conjunction ) a solution ( sulphate ( nickel or1 bett]1 a solution ( nickel ammonium sulphate1 made by cry/alliz+ ammonium & nickel sulphates toge!r4 ,! curr5t requir$ is small2 inde$1 if x is too /rong1 ! deposit adh]es loosely to ! article1 & ! result is1 !re=e1 n satisfactory4 ,electrotype blocks are also made by a simil> process4 ,an impression ( ! article to be reproduc$ is made 9 wax1 or "s suitable pla/ic mat]ial1 & poli%$ ) v f9e graphite or black lead1 9 ord] to give a conduct+ surface4 ,x is !n susp5d$ 9 a solution ( copp] sulphate & jo9$ to ! negative pole ( ! batt]y2 a plate ( copp] connect$ ) ! positive pole is susp5d$ 9 ! same solution4 ,:5 a weak curr5t is pass$1 copp] is deposit$ on ! black-lead$ surface & gr[s gradually 9 ?ickness1 until at l5g? x c be /ripp$ (f1 giv+ a positive replica ( ! object4 ,,index ,a ,acetic acid 7glacial71 #gc ,acids1 e>ly notions (1 #a ----1 fatty1 #gh ----1 m9]al1 #fh ----1 vegetable1 #fh ,agate1 #fa ,air-saltpetre1 #db ,alkali ,acts1 #dd ----1 cau/ic1 #if ----1 metals1 #ie ----1 mild1 #hj ---- wa/e1 #hg ,alkalis1 prop]ties1 #c ,alum9ium acetate1 #gc ,alums1 !1 #bf ,ame?y/1 #fa ,ammonal1 #cf ,ammonia1 #ig ----1 syn!tic1 #ii ,ammonite1 #ii ,ammonium c>bonate1 #ii ---- *loride1 #ih ---- nitrate1 #ii ---- sulphate1 #ii ,anhydride1 an1 #ba ,anode1 #ajc ,argol1 #gf ,asbe/os1 #fc ----1 plat9iz$1 #ai ,a%1 black1 #hd ----1 pe>l1 #ic ----1 soda1 #aj1 #ib ,atolls1 #ea ,atomiz$ wat]1 #ah ,b ,bacon1 ,rog]1 #cb ,basic slag1 #eh ,basil ,val5t9e1 #ab ,b]yl1 #fc ,black liquor1 #gd ,bla/+ gelat9e1 #ce ,blea*+ p[d]1 #df ,blue-john1 #dg ,boil] scale1 #ed ,bonbonnes1 #ca ,bone1 #ef ---- a%1 #eg ---- black1 #ef ---- meal1 #ef ,borax1 #ei ,bordeaux mixture1 #g ,boric acid1 #eh ,boyle1 ,rob]t1 #b ,burgundy mixture1 #f ,c ,calcium acetate1 #e ---- bic>bonate1 #ed ---- c>bonate1 #ej ---- fluoride1 #dg ---- nitrate1 #bi ---- phosphate1 #ef ---- sulphate1 #bg ,calc sp>1 #ej ,cali*e1 #bi ,calico pr9t+1 #bf ,c>bon1 #di ,c>bonic acid1 #di ---- ---- gas1 #di ,ca/n] process1 #aje ,catalytic action1 #bj ,ca?ode1 #ajc ,cat's-eye1 #fa ,cav5di%1 ,h41 #dj ,cellulose1 #df ,*alc$ony1 #fa ,*alk1 #ej ,*]t1 #ff ,*ili-saltpetre1 #bi1 #ci ,*9a clay1 #fb ,citric acid1 #gg ,*lorides1 #dg ,*lor9e1 #df ,*rome yell[1 #bh ---- r$1 #bh ,comp\nd1 #g ,comp\nds1 b9>y1 #h ,contact action1 #bj ---- process1 #ah ,copp] ref9+1 #ajg ---- sulphate1 #e1 #bg ,coral reefs1 #ea ,cordite1 #cd ,cream ( t>t>1 #gf ,crops1 rotation (1 #cg ,cry/allization1 wat] (1 #i ,cry/als1 #i ,d ,davy1 ,sir ,humphry1 #ie ,d]by%ire sp>1 #dg ,devitrification1 #fe ,dynamite1 #ce ,e ,effloresc5ce1 #hb ,electrode1 #ajc ,electrolysis1 #ajb ,electrons1 #ajc ,electrotype blocks1 #ajg ,elem5t1 def9ition (1 #g ,elem5ts1 li/ (1 #h ,explosives1 #cb ,f ,felsp>s1 #fb ,f]r\s acetate1 #gd ---- sulphate1 #be ,fl9t1 #fa ,fluorsp>1 #dh ,=mic acid1 #gh ,fur 9 kettles1 #ed ,g ,g>net1 #fc ,gas1 laugh+1 #ii ---- lime1 #ab ---- liquor1 #ih ,gay ,lussac t[]1 #af ,glass1 #fd ----1 anneal+ (1 #fe ----1 ,bohemian1 #fc ----1 et*+ on1 #dg ----1 fl9t1 #fc ----1 lead1 #fc ----1 soda1 #fc ----1 wat]1 #ff ,glaub]'s salt1 #aj ,glov] t[]1 #ag ,glue1 #ef ,graphite1 #ajh ,greek fire1 #cb ,guncotton1 #cd ,gunp[d]1 #cb ,gypsum1 #bg ,h ,hab] process1 #ajj ,halog51 #dc ,h>dness1 p]man5t1 #ec ----1 tempor>y1 #ec ,h>t%orn1 salt (1 #ii ----1 spirits (1 #ig ,hornbl5de1 #fc ,hydriodic acid1 #dh ,hydrobromic acid1 #dh ,hydro*loric acid1 #dc ,hydr(luoric acid1 #dg ,i ,icel& sp>1 #ej ,ions1 #ajc ,iron pyrites1 #aa ,j ,jade1 #fc ,jasp]1 #fa ,k ,key indu/ries1 #aj ,l ,lake1 #bf ,lead acetate1 #ge ---- *amb]s1 #ag ---- *amb] process1 #ad ----1 sug> (1 #ge ---- sulphate1 #bg ----1 :ite1 #ge ,leblanc soda process1 #hb ,legum9osae1 #cg ,lemon1 salts (1 #gg ,lime burn+1 #ea ----1 cau/ic1 #ig ---- kiln1 #ea ,lime/one1 #ej ,litmus1 #b ,lup9 root1 #cg ,m ,m>ble1 #ej ,m>k+ ink1 #bh ,me]s*aum1 #fc ,mica1 #fc ,mordants1 #bf ,mycod]ma aceti1 #fh ,n ,neutralization1 example (1 #d ----1 explanation (1 #c ,niag>a1 #aja ,nitre1 #bi ---- pots1 #ad ,nitric acid1 #cj ---- ----1 f air1 #dj ---- ----1 importance (1 #bh ---- ---- manufacture (1 #cj ---- ----1 prop]ties1 #ca ---- ----1 r$ fum+1 #ca ---- oxide1 #af ,nitrog5 cycle1 #cg ----1 fixation (1 #ajj ---- p]oxide1 #af ,nitroglyc]9e1 #cd ,o ,ole91 #gh ,onyx1 #fa ,opal1 #fa ,or?oclase1 #fb ,oxalic acid1 #gg ,p ,palmit91 #gh ,pe>ls1 #ea ,p]egr9e ,phillips1 #ba ,philosoph]'s /one1 #b ,phosphoric acid1 #eg ,pla/] ( ,p>is1 #bg ,pota%1 cau/ic1 #ig ----1 mild1 #ic ,potassium1 #ie ---- bic>bonate1 #id ---- nitrate1 #bi ,propellants1 #cc ,prussian blue1 #be ,pyrites burn]s1 #ad ,pyroligne\s acid1 #gc ,q ,qu>tz1 #fa ---- fibres1 #fb ----1 smoky1 #fa ,quicklime1 #e1 #ea ,r ,r$ liquor1 #gc ,rock cry/al1 #fa ,rup]t's drops1 #fe ,s ,sal ammoniac1 #ii ---- prunella1 #bi ,salt cake1 #hd ----1 common1 #dg ----1 =mation ( a1 #d ,saltpetre1 #bi ,salts1 f c>bonates1 #e ----1 f oxides1 #e ----1 f metals1 #d ----1 insoluble1 #f ,s&/one1 artificial1 #ff ,saponification1 #gi ,s*we9furt gre51 #bg ,%ells1 egg1 #ea ----1 oy/]1 #ea ,silica1 #fa ---- w>e1 #fb ,silicic acid1 #fb ,silv] bromide1 #dh ---- *loride1 #dh ---- iodide1 #dh ---- nitrate1 #bh ---- s&1 #fa ,soap1 h>d1 #gi ----1 s(t1 #gi ,soda1 bak+1 #hh ----1 bic>bonate (1 #f1 #hh ----1 bread1 #hh ----1 cau/ic1 #if ----1 mild1 #hj ----1 natural1 #hb ----1 wa%+1 #c1 #e1 #ha ---- wat]1 #di ,sodium1 #ie ---- nitrate1 #bi ---- sulphate1 #bg ,soil bact]ia1 #ch ,solvay process1 #ij ,sorrel1 salts (1 #gg ,sp5t oxide1 #aa ,/alactite1 #ec ,/alagmite1 #ec ,/e>91 #gh ---- c&les1 #gi ,/one ammonia1 #ii ,suffioni1 #fj ,sulphur1 #aa ---- dioxide1 #aa ---- trioxide1 prep4 (1 #ai ,sulphuric acid1 prop]ties1 #bj1 #bd ---- anhydride1 #ba ,sulphur\s acid1 #aa ,sup]phosphate1 #eg ,t ,tall[1 #gi ,t>t>ic acid1 #gf ,t9kal1 #fa ,tr9itrotolu5e1 #ce ,v ,v]digris1 #gd ,v]t de ,montpelli]1 #gd ,v9eg>1 #fh ----1 malt1 #gj ----1 w9e1 #gj ,vitriol1 blue1 #e ----1 nitrat$1 #af ----1 oil (1 #ab ,w ,w>d1 ,dr41 #ab ,wat]1 h>d1 #ec ----1 s(t1 #ec ----1 s(t5+ (1 #ed ,wood a%es1 s\rce ( pota%1 #c ---- ----1 us$ z soap1 #b ,z ,z9c *loride1 #e ,,! ,,end ,footnotes #a;,an anhydride is a sub/ance :i* unites ) wat] to =m an acid4 #b,see ,frontispiece4 #c,n[ #ac a ton4 #d;,basic lead c>bonate4 #e;,an electron is probably an 8atom0 ( negative electricity deta*$ f matt]4 ,pr9t$ by ,sir ,isaac ,pitman ,sons1 ,ltd4 ,ba?1 ,engl& 7v--#adfh;c7 ,transcrib]'s ,notes --,sil5tly correct$ sev]al palpable typographical errors4 --,reta9$ publication in=mation f ! orig9al s\rce4 --,9 ! text v]sions1 includ$ italiciz$ text 9 und]scores4