,,contributions ,,f ,,! ,,museum ,,( ,,hi/ory ,,& ,,te*nology3 ,,pap] #ai ,,elevator ,,sy/ems ,,( ,,! ,,eiffel ,,t[]1 #ahhi ,rob]t ,m4 ,vogel ,,prep>atory ,,"w ,,= ,,! ,,t[] #d ,,! ,,t[]',s ,,/ructural ,,rationale #e ,,elevator ,,developm5t ,,be=e ,,! ,,t[] #f ,,! ,,t[]',s ,,elevators #bj ,,epilogue #cg ,,elevator ,,sy/ems ( ! ,,eiffel ,,t[]1 #ahhi ,by ,rob]t ,m4 ,vogel ,?is article traces ! evolution ( ! p[]$ pass5g] elevator f its initial developm5t 9 ! mid-#ai? c5tury to ! in/allation ( ! ?ree sep>ate elevator sy/ems 9 ! ,eiffel ,t[] 9 #ahhi4 ,! design ( ! ,t[]'s elevators involv$ problems ( capacity1 l5g? ( rise1 & safety f> great] ?an any previ\sly enc\nt]$ 9 ! field2 & ! equipm5t t result$ 0 ! fir/ capable ( meet+ ! conditions ( v]tical transportation f\nd 9 ! j em]g+ skyscrap]4 ,,! ,,au?or3 ,rob]t ,m4 ,vogel is associate curator ( me*anical & civil eng9e]+1 ,unit$ ,/ates ,national ,museum1 ,smi?sonian ,in/itution4 ,! #a1jjj-;foot t[] t =m$ ! focal po9t & c5tral feature ( ! ,univ]sal ,exposition ( #ahhi at ,p>is has become "o ( ! be/ kn[n ( man's works4 ,x 0 among ! mo/ out/&+ te*nological a*ievem5ts ( an age :i* 0 itself rem>kable = su* a*ievem5ts4 ,second to ! int]e/ %[n 9 ! t[]'s /ructural aspects 0 ! int]e/ 9 its me*anical organs4 ,( ^!1 ! mo/ exceptional 7 ! ?ree sep>ate elevator sy/ems by :i* ! upp] levels 7 made accessible to ! ,exposition visitors4 ,! design ( ^! sy/ems involv$ problems f> great] ?an _h be5 enc\nt]$ 9 previ\s elevator "w any:]e 9 ! _w4 ,! basis ( ^! difficulties 0 ! amplification ( ! two conditions t 7 ! normal det]m9ants 9 elevator design--pass5g] capacity & height ( rise4 ,9 addition1 !re 0 ! problem1 totally new1 ( fitt+ elevator %afts to ! curvature ( ! ,t[]'s legs4 ,! /udy ( ! v>i\s solutions to ^! problems pres5ts a concise view ( ! capabilities ( ! elevator art j prior to ! beg9n+ ( ! mo/ rec5t phase ( its developm5t1 m>k$ by ! entry ( electricity into ! field4 ,! great confid5ce ( ! ,t[]'s build] 9 8 own eng9e]+ ability c be fully appreciat$1 h[ev]1 only :5 notice is tak5 ( "o exceptional way 9 :i* ! project diff]$ f works ( e>li] p]iods z well z f contempor>y ones4 ,9 almo/ e case1 ^! o!r works _h evolv$1 9 a natural & progressive way1 f a fundam5tal concept firmly bas$ ^u prec$5t4 ,?is 0 true ( su* notable /ructures ( ! "t z ! ,brooklyn ,bridge &1 to a less] ext5t1 ! ,=? ,bridge4 ,= ! design ( 8 t[]1 !re 0 virtually no exp]i5ce 9 /ructural hi/ory f :i* ,eiffel c\ld draw o!r ?an a s]ies ( high pi]s t 8 own firm _h design$ e>li] = railway bridges4 ,x 0 ^! designs t l$ ,eiffel to consid] ! practicality ( iron /ructures ( extreme height4 ,illu/ration3 ,figure #a4--,! ,eiffel ,t[] at ! "t ( ! ,univ]sal ,exposition ( #ahhi at ,p>is4 7,f ,la ,nature1 ,june #bi1 #ahhi1 vol4 #ag1 p4 #gc47 ,illu/ration3 ,figure #b4--;,gu/ave ,eiffel 7#ahcb-aibc74 7,f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 frontispiece47 ,!re 01 x is true1 "s inspiration to be f\nd 9 ! pap] projects ( sev]al e>li] design]s--!mselves inspir$ by t compulsion :i* ?r\gh\t hi/ory seems to h driv5 m5 to attempt ! erection ( magnific5tly high /ructures4 ,"o su* inspiration 0 a proposal made 9 #ahcb by ! celebrat$ b ecc5tric ,wel% eng9e] ,ri*>d ,trevi?ick to erect a #a1jjj-;foot1 conical1 ca/-iron t[] 7fig4 #c7 to celebrate ! pass+ ( ! ,re=m ,bill4 ,( p>ticul> int]e/ 9 light ( ! pres5t discussion 0 ,trevi?ick's plan to raise visitors to ! summit on a pi/on1 driv5 upw>d )9 ! /ructure's holl[ c5tral tube by compress$ air4 ,x probably is =tunate = ,trevi?ick's reputation t 8 plan di$ %ortly aft] ?is & ! project 0 =gott54 ,"o project ( g5u9e promise 0 a t[] propos$ by ! em95t ,am]ican eng9e]+ firm ( ,cl>ke1 ,reeves ,company to be erect$ at ! ,c5t5nial ,exhibition at ,philadelphia 9 #ahgf4 ,at ! "t1 ?is firm 0 p]haps ! lead+ design] & erector ( iron /ructures 9 ! ,unit$ ,/ates1 hav+ execut$ su* works z ! ,gir>d ,av5ue ,bridge ov] ! ,s*uylkill at ,fairm\nt ,p>k1 & mo/ ( ,new ,york's e>ly elevat$ railway sy/em4 ,! company's proposal 7fig4 #d7 = a #a1jjj-;foot %aft ( wr\ght-iron columns brac$ by a cont9u\s web ( diagonals 0 bas$ ^u s\nd !oretical k & practical exp]i5ce4 ,nev]!less1 ! natural hesitation t ! fair's sponsors app>5tly felt 9 ! face ( s h]oic a s*eme c\ld n be ov]come1 & ?is project also rema9$ a vision4 ,prep>atory ,"w = ! ,t[] ,9 ! ye> #ahhe1 ! ,eiffel firm1 :i* also _h an ext5sive backgr\nd ( exp]i5ce 9 /ructural eng9e]+1 und]took a s]ies ( inve/igations ( tall metallic pi]s bas$ ^u its rec5t exp]i5ces ) sev]al l(ty railway viaducts & bridges4 ,! mo/ spectacul> ( ^! 0 ! fam\s ,g>abit ,viaduct 7#ahhj-ahhd71 :i* c>ries a railroad "s #djj feet above ! valley ( ! ,truy]e 9 s\!rn ,france4 ,:ile ! #bjj-;foot height ( ! viaduct's two greate/ pi]s 0 n />tl+ ev5 at t p]iod1 ! /udies prov$ t pi]s ( f> great] height 7 entirely feasible 9 iron con/ruction4 ,?is l$ to ! design ( a #cie-;foot pi]1 :i*1 al?\gh nev] incorporat$ into a bridge1 may be said to h be5 ! direct basis = ! ,eiffel ,t[]4 ,prelim9>y /udies = a #cjj-met] t[] 7 made ) ! #ahhi fair imm$iately 9 m9d4 ,) an assurance born ( positive k1 ,eiffel 9 ,june ( #ahhf approa*$ ! ,exposition commission]s ) ! project4 ,!re c be no d\bt t only ! s+ul> respect ) :i* ,eiffel 0 reg>d$ n only by 8 pr(ession b by ! entire nation motivat$ ! ,commission to approve a plan :i*1 9 ! h&s ( a figure ( less /ature1 w\ld h be5 consid]$ grossly impractical4 ,betwe5 ?is "t & comm5cem5t ( ! ,t[]'s con/ruction at ! end ( ,janu>y #ahhg1 !re arose "o ( ! mo/ p]si/5tly annoy+ ( ! num]\s difficulties1 bo? /ructural & social1 :i* confront$ ,eiffel z ! project advanc$4 ,9 ! wake ( ! initial en?usiasm--on ! "p ( ! fair's ,commission inspir$ by ! desire to create a monum5t to ,fr5* te*nological a*ievem5t1 & on ! "p ( ! majority ( ,fr5*m5 by ! /irr+ ( _! imag9ation at ! magnitude ( ! /ructure--!re grew a ris+ movem5t ( disfavor4 ,! nucleus 01 n surpris+ly1 =m$ ma9ly ( ! intellig5tsia1 b objections 7 made by prom95t ,fr5*m5 9 all walks ( life4 ,! mo/ int]e/+ po9t to be not$ 9 a retrospection ( ?is (t5 viol5t opposition 0 t1 al?\gh ! ,t[]'s e aspect 0 attack$1 !re 0 rem>kably little criticism ( its /ructural feasibility1 ei!r by ! eng9e]+ pr(ession or1 z seems traditionally to be ! case ) bold & unprec$5t$ und]tak+s1 by l>ge numb]s ( ! te*nically un9=m$ laity4 ,true1 !re 0 an und]curr5t ( :at might be *>act]iz$ z unease by _m prop]ty own]s 9 ! /ructure's %ad[1 b ! mo/ ob/9ate elem5t ( resi/ance 0 t :i* deplor$ ! ,t[] z a me*ani/ic intrusion ^u ! ar*itectural & natural beauties ( ,p>is4 ,?is resi/ance voic$ its fury 9 a flood ( special newspap] editions1 petitions1 & manife/os sign$ by su* lights ( ! f9e & lit]>y arts z ,de ,maupassant1 ,g\nod1 ,dumas fils1 & o!rs4 ,! eloqu5ce ( "o article1 :i* appe>$ 9 sev]al ,p>is pap]s 9 ,febru>y #ahhg1 0 typical3 ,we prote/ 9 ! "n ( ,fr5* ta/e & ! national art culture aga9/ ! erection ( a /agg]+ ,t[]1 l a gigantic kit*5 *imney dom9at+ ,p>is1 eclips+ by its b>b>\s mass ,notre ,dame1 ! ,sa9te-,*apelle1 ! t[] ( ,/4 ,jacques1 ! ,dme des ,invalides1 ! ,arc de ,triomphe1 humiliat+ ^! monum5ts by an act ( madness4#a ,fur!r1 a pr$iction 0 made t ! entire city w\ld become di%onor$ by ! odi\s %ad[ ( ! odi\s column ( bolt$ %eet iron4 ,x is impossible to det]m9e :at influ5ce ^! outcries might h _h on ! project _h !y be5 organiz$ soon]4 ,b inasmu* z ! ,commission _h1 9 ,novemb] #ahhf1 provid$ #a1ejj1jjj francs = its comm5cem5t1 ! "w _h be5 fairly laun*$ by ! "t ! prote/ations became l\d en\gh to ?reat5 & !y 7 ineffectual4 ,^u completion1 _m ( ! mo/ vigor\s prote/ants became z vigor\s 9 _! praise ( ! ,t[]1 b a h>d core ( critics cont9u$ = sev]al ye>s to circulate petitions advocat+ its demolition by ! gov]nm5t4 ,"o ( ^! critics1 x 0 said--probably apocryphally--took an (fice on ! fir/ plat=m1 t be+ ! only place 9 ,p>is f :i* ! ,t[] c\ld n be se54 ,illu/ration3 ,figure #c4--,trevi?ick's propos$ ca/-iron t[] 7#ahcb7 w\ld h be5 #a1jjj feet high1 #ajj feet 9 diamet] at ! base1 #ab feet at ! top1 & surm\nt$ by a colossal /atue4 7,f ,f4 ,dye1 ,popul> ,eng9e]+1 ,london1 #ahie1 p4 #bje47 ,! ,t[]'s ,/ructural ,rationale ,dur+ ! previ\sly m5tion$ /udies ( high pi]s und]tak5 by ! ,eiffel firm1 x 0 e/abli%$ t z ! base wid? ( ^! pi]s increas$ 9 proportion to _! height1 ! diagonal brac+ connect+ ! v]tical memb]s1 necess>y = rigidity1 became s long z to be subject to high flexural /resses f w9d & column> load+4 ,to resi/ ^! /resses1 ! brac+ requir$ extremely l>ge sections :i* greatly increas$ ! surface ( ! /ructure expos$ to ! w9d1 & 01 moreov]1 decid$ly uneconomical4 ,to ov]come ?is difficulty1 ! pr9ciple :i* became ! basic design concept ( ! ,t[] 0 develop$4 ,! mat]ial :i* w\ld o!rwise h be5 us$ = ! cont9u\s lattice ( diagonal brac+ 0 conc5trat$ 9 ! f\r corn] columns ( ! ,t[]1 & ^! v]ticals 7 connect$ only at two widely sep>at$ po9ts by ! deep b&s ( truss+ :i* =m$ ! fir/ & second plat=ms4 ,a slight curvature inw>d 0 giv5 to ! ma9 pi]s to fur!r wid5 ! base & increase ! /ability ( ! /ructure4 ,at a po9t slightly above ! second plat=m1 ! f\r memb]s conv]g$ to ! ext5t t conv5tional brac+ became m economical1 & !y 7 jo9$4 ,illu/ration3 ,figure #d4--,! propos$ #a1jjj-;foot iron t[] design$ by ,cl>ke1 ,reeves ,co4 = ! ,c5t5nial ,exhibition ( #ahgf at ,philadelphia4 7,f ,sci5tific ,am]ican1 ,jan4 #bd1 #ahgd1 vol4 #cj1 p4 #dg47 ,t ?is !ory 0 successful n only practically1 b visually1 is evid5t f ! result+ "w4 ,! curve ( ! legs & ! op5+s b5ea? ! two l[] plat=ms are prim>ily responsible = ! ,t[]'s graceful beauty z well z = its /ructural s\ndness4 ,! design ( ! ,t[] 0 n actually ! "w ( ,eiffel himself b ( two ( 8 *ief eng9e]s1 ,emile ,n\gui] 7#ahdj-87 & ,maurice ,koe*l9 7#ahef-aidf7--! m5 :o _h conduct$ ! high pi] /udies--& ! ar*itect ,/ph5 ,sauve/re 7#ahdg-874 ,9 ! plann+ ( ! f\ndations1 extreme c>e 0 us$ to ensure adequate foot+1 b 9 spite ( ! ,t[]'s light weight 9 proportion to its bulk1 & ! l[ e>? pressure x ex]t$1 unev5 pi] settlem5t ) resultant lean+ ( ! ,t[] 0 consid]$ a dang]\s possibility4#b ,to comp5sate = ?is ev5tuality1 a device 0 us$ ^: +5i\s directness ju/ifies a brief description4 ,9 ! base ( ea* ( ! #af columns =m+ ! f\r ma9 legs 0 incorporat$ an op5+ into :i* an #hjj-ton hydraulic press c\ld be plac$1 capable ( rais+ ! memb] slightly4 ,a ?9 /eel %im c\ld !n be ins]t$ to make ! necess>y correction 7fig4 #e74 ,! sy/em 0 us$ only dur+ con/ruction to ov]come m9or erection discrepancies4 ,9 ord] to appreciate fully ! problem :i* confront$ ! ,t[]'s design]s & sponsors :5 !y turn$ to ! problem ( mak+ its obs]vation areas accessible to ! fair's visitors1 x is fir/ necess>y to inve/igate briefly ! contempor>y /ate ( elevator art4 ,elevator ,developm5t be=e ! ,t[] ,:ile p[]-driv5 hoi/s & elevators 9 _m =ms _h be5 us$ s9ce ! e>ly ye>s ( ! #ai? c5tury1 ! ev]-pres5t possibility ( breakage ( ! hoi/+ rope re/rict$ _! use almo/ entirely to ! h&l+ ( goods 9 mills & w>eh\ses4#c ,n until ! inv5tion ( a device :i* w\ld positively prev5t ?is 0 !re mu* basis = "w on o!r elem5ts ( ! sy/em4 ,! fir/ workable me*anism to prev5t ! c> f dropp+ to ! bottom ( ! hoi/way 9 ev5t ( rope failure 0 ! product ( ,eli%a ,g4 ,otis 7#ahaa-ahfa71 a me*anic ( ,yonk]s1 ,new ,york4 ,! inv5tion 0 made m or less z a matt] ( c\rse along ) ! o!r ma*9]y = a new mattress factory ( :i* ,otis 0 ma/] me*anic4 ,illu/ration3 ,figure #e4--;,correct+ erection discrepancies by rais+ pi] memb]--) hydraulic press & h& pump--& ins]t+ %ims4 7,f ,la ,nature1 ,feb4 #ah1 #ahhh1 vol4 #af1 p4 #ahd47 ,illu/ration3 ,figure #f4--,! prom5ade b5ea? ! ,eiffel ,t[]1 #ahhi4 7,f ,la ,nature1 ,nov4 #cj1 #ahhi1 vol4 #ag1 p4 #dbe47 ,illu/ration3 ,figure #g4--,teagle elevator 9 an ,engli% mill ab\t #ahde4 ,p[] 0 tak5 f ! l9e %aft+4 7,f ,pictorial ,gall]y ( ,arts1 ,volume ( ,useful ,arts1 ,london1 n4d4 ca4 #ahde47 ,! importance ( ?is inv5tion soon became evid5t to ,otis1 & he introduc$ 8 device to ! public ?ree ye>s lat] dur+ ! second season ( ! ,new ,york ,cry/al ,palace ,exhibition1 9 #ahed4 ,"h he w\ld demon/rate dramatically ! p]fect safety ( 8 elevator by cutt+ ! hoi/+ rope ( a susp5d$ plat=m on :i* he himself /ood1 utt]+ ! immortal words :i* h come to be insep>ably associat$ ) ! hi/ory ( ! elevator--,all safe1 g5tlem56#d ,! inv5tion a*iev$ popul>ity sl[ly1 b did f9d increas+ favor 9 manufactories ?r\gh\t ! ea/]n ,unit$ ,/ates4 ,! significance ( ,otis' e>ly "w 9 ?is field lay /rictly 9 ! safety features ( 8 elevators r ?an 9 ! hoi/+ equipm5t4 ,8 e>lie/ sy/ems 7 op]at$ by ma*9]y simil> to t ( ! teagle elevator 9 :i* ! hoi/+ drum 0 driv5 f ! mill %aft+ by simple fa/ & loose pulleys ) cross$ & /raight belts to raise1 l[]1 & /op4 ,?is s*eme1 already common at ! "t1 0 itself a direct improvem5t on ! anci5t h&-p[]$ drum hoi/4 ,! fir/ complete elevator ma*9e 9 ! ,unit$ ,/ates1 con/ruct$ 9 #ahee1 0 a complex & ineffici5t contrivance built ar\nd an oscillat+-cyl9d] /eam eng9e4 ,! advantages ( an elevator sy/em indep5d5t ( ! mill drive quickly became app>5t1 & by #ahfj improv$ /eam elevator ma*9es 7 be+ produc$ 9 "s quantity1 b almo/ exclusively = freight s]vice4 ,x is n cle> :5 ! fir/ elevator 0 in/all$ explicitly = pass5g] s]vice1 b x 0 probably 9 #aheg1 :5 ,otis plac$ "o 9 a /ore on ,broadway at ,broome ,/reet 9 ,new ,york4 ,9 ! decade foll[+ ! ,civil ,w>1 tall build+s _h j begun to em]ge2 &1 al?\gh ! skyl9es ( ! _w's great cities 7 /ill dom9at$ by *ur* spires1 !re 0 increas+ activity 9 ! developm5t ( elevator app>atus adapt$ to ! transportation ( p z well z ( m]*&ise4 ,op]ators ( hotels & /ores gradually became aw>e ( ! comm]cial advantages to be ga9$ by elevat+ _! patrons ev5 "o or two floors above ! gr\nd1 by ma*9]y4 ,! /eam eng9e =m$ ! f\ndation ( ! e>ly elevator indu/ry1 b z build+ heights increas$ x 0 gradually replac$ by hydraulic1 & ultimately by electrical1 sy/ems4 ,,! ,,/eam ,,elevator ,! progression f an elevator ma*9e p[]$ by ! l9e %aft+ ( a mill to "o 9 :i* ! p[] s\rce 0 indep5d5t w\ld appe> a simple & direct "o4 ,nev]!less1 x 0 ab\t #dj ye>s aft] ! introduction ( ! p[]$ elevator be=e x became common to c\ple elevator ma*9es directly to sep>ate eng9es4 ,! multiple belt & pulley transmission sy/em 0 at fir/ reta9$1 b x soon became evid5t t a m satisfactory s]vice result$ f /opp+ & rev]s+ ! eng9e itself1 us+ a s+le fix$ belt to connect ! eng9e & w9d+ me*anism4 ,int]e/+ly1 ! same patt]n 0 foll[$ #dj ye>s lat] :5 ! fir/ attempts 7 made to apply ! electric motor to elevator drive4 ,illu/ration3 ,figure #h4--;,9 ! typical /eam elevator ma*9e two v]tical cyl9d]s 7 situat$ ei!r above or bel[ ! crank%aft1 & a small pulley 0 key$ to ! crank%aft4 ,9 a light-duty ma*9e1 ! p[] 0 transmitt$ by flatbelt f ! small pulley to a l>g] "o m\nt$ directly on ! drum4 ,9 heavy-duty ma*9es1 spur ge>+ 0 int]pos$ betwe5 ! l>ge second>y pulley & ! w9d+ drum4 7,photo c\rtesy ( ,otis ,elevator ,company47 ,illu/ration3 ,figure #i4--,sev]al manufactur]s built /eam ma*9es 9 :i* a ge> on ! drum %aft me%$ directly ) a worm on ! crank%aft4 ,?is arrangem5t elim9at$ ! belt1 &1 s9ce ! drum c\ld n drive ! eng9e ?r\gh ! worm ge>+1 no brake 0 necess>y = hold+ ! load4 7,c\rtesy ( ,otis ,elevator ,company47 ,by #ahgj ! /eam elevator ma*9e _h atta9$ its ultimate =m1 :i*1 except = a numb] ( m9or ref9em5ts1 0 to rema9 un*ang$ until ! type became completely obsolete t[>d ! end ( ! c5tury4 ,by ! la/ qu>t] ( ! c5tury1 a cont9u\s s]ies ( improvem5ts 9 ! valv+1 control sy/ems1 & safety features ( ! /eam ma*9e _h made possible an elevator able to compete ) ! subsequ5tly appe>+ hydraulic sy/ems = freight & l[-rise pass5g] s]vice ins(> z smoo?ness1 control1 & lift+ p[] 7 conc]n$4 ,h[ev]1 /eam ma*9]y began to fail 9 ?is competition z ! increas+ height ( build+s rapidly ext5d$ ! dem&s ( spe$ & l5g? ( rise4 ,! limitation 9 rise con/itut$ ! mo/ s]i\s %ortcom+ ( ! /eam elevator 7figs4 #h-aj71 an inh]5t defect t did n exi/ 9 ! v>i\s hydraulic sy/ems4 ,illu/ration3 ,figure #aj4--;,compon5ts ( ! /eam pass5g] elevator at ! "t ( its peak developm5t & use 7#ahgf74 7,f ,! ,fir/ ,"o ,hundr$ ,ye>s1 ,otis ,elevator ,company1 #aiec47 ,s9ce ! only practical way 9 :i* ! p[] ( a /eam eng9e c\ld be appli$ to ! haulage ( elevator cables 0 ?r\gh a rotational sy/em1 ! cables inv>iably 7 w\nd on a drum4 ,! travel or rise ( ! c> 0 !re=e limit$ by ! cable capacity ( ! w9d+ drum4 ,z build+ heights increas$1 drums became necess>ily long] & l>g] until !y grew s cumb]some z to impose a s]i\s limitation ^u fur!r upw>d gr[?4 ,a drum ma*9e r>ely c\ld be us$ = a lift ( m ?an #aej feet4#e ,ano!r organic difficulty exi/+ 9 drum ma*9es 0 ! dang]\s possibility ( ! c>--or ! c\nt]weight1 ^: cables (t5 w\nd on ! drum--be+ drawn pa/ ! normal top limit & into ! upp] support+ works4 ,only safety /ops c\ld prev5t su* an occurr5ce if ! op]ator fail$ to /op ! c> at ! top or bottom ( ! %aft1 & ev5 ^! 7 n always effective4 ,hydraulic ma*9es 7 n susceptible to ?is dang]1 ! pi/on or plung] be+ arre/$ by ! ends ( ! cyl9d] at ! extremes ( travel4 ,,! ,,hydraulic ,,elevator ,! rope-ge>$ hydraulic elevator1 :i* 0 ev5tually to become kn[n z ! /&>d ( ! indu/ry1 is g5]ally ?\ght to h evolv$ directly f an inv5tion ( ! ,engli% eng9e] ,sir ,william ,arm/rong 7#ahaj-aijj7 ( ordnance fame4 ,9 #ahdf he develop$ a wat]-p[]$ crane1 utiliz+ ! hydraulic head available f a res]voir on a hill #bjj feet above4 ,! sy/em 0 n basically diff]5t f ! simple hydraulic press s well kn[n at ! "t4 ,wat]1 admitt$ to a horizontal cyl9d]1 displac$ a pi/on & rod to :i* a %eave 0 atta*$4 ,ar\nd ! %eave pass$ a loop ( *a91 "o end ( :i* 0 fix$1 ! o!r runn+ ov] guide %eaves & t]m9at+ at ! crane arm ) a lift+ hook4 ,z ! pi/on 0 press$ into ! cyl9d]1 ! free end ( ! *a9 0 drawn up at triple ! pi/on spe$1 rais+ ! load4 ,! effect 0 simply t ( a #c-to-#a tackle1 ) ! ef=t & load elem5ts rev]s$4 ,simple valves controll$ admission & exhau/ ( ! wat]4 7,see fig4 #aa47 ,illu/ration3 ,figure #aa4--;,arm/rong's hydraulic crane4 ,! ma9 cyl9d] 0 incl9$1 p]mitt+ gravity to assi/ 9 ov]haul+ ! hook4 ,! small cyl9d] rotat$ ! crane4 7,f ,john ,h4 ,jall+s1 ,elevators1 ,*icago1 #aiaf1 p4 #hb47 ,! success ( ?is sy/em initiat$ a sizable indu/ry 9 ,engl&1 & ! hydraulic crane1 ) _m modifications1 0 9 common use !re = _m ye>s4 ,su* cranes 7 introduc$ 9 ! ,unit$ ,/ates 9 ab\t #ahfg b nev] became popul>2 !y did1 h[ev]1 h a pr(\nd influ5ce on ! elevator art1 =m+ ! basis ( ! ?ird g5]ic type to a*ieve widespread use 9 ?is c\ntry4 ,! ease ( translation f ! ,arm/rong crane to an elevator sy/em c\ld h>dly h be5 m evid5t1 only two alt]ations ( consequ5ce be+ necess>y 9 ! passage4 ,a guid$ plat=m or c> 0 sub/itut$ = ! hook2 & ! control valves 7 connect$ to a /ation>y endless rope t 0 accessible to an op]ator on ! c>4 ,! rope-ge>$ hydraulic sy/em 7fig4 #ac7 appe>$ 9 mature =m 9 ab\t #ahgf4 ,h[ev]1 be=e x _h become ! /&>d elevator ?r\gh a process ( ref9em5t1 ano!r sy/em 0 introduc$ :i* m]its notice if = no o!r reason ?an t its popul>ity = "s ye>s seems rem>kable 9 view ( its prepo/]\sly unsafe design4 ,pat5t$ by ,cyrus ,w4 ,baldw9 ( ,bo/on 9 ,janu>y #ahgj1 ?is sy/em 0 t]m$ ! ,hydro-,atmosph]ic ,elevator1 b m commonly kn[n z ! wat]-balance elevator 7fig4 #ab74 ,x employ$ wat] n "u pressure b simply z mass "u ! influ5ce ( gravity4 ,! elevator c>'s support+ cables ran ov] %eaves at ! top ( ! %aft to a l>ge iron bucket1 :i* travel$ 9 a clos$ tube or well adjac5t to & ! same l5g? z ! %aft4 ,to raise ! c>1 ! op]ator caus$ a valve to op51 fill+ ! bucket ) wat] f a ro( tank4 ,:5 ! weight ( wat] 0 suffici5t to ov]balance ! load$ c>1 ! bucket desc5d$1 rais+ ! c>4 ,on its asc5t ! c> 0 /opp$ at int]m$iate floors by a /rong brake t gripp$ ! guides4 ,^u rea*+ ! top1 ! op]ator 0 able to op5 a valve 9 ! bucket1 n[ at ! bottom ( its travel1 & dis*>ge its cont5ts into a basem5t tank1 to be pump$ back to ! ro(4 ,no long] c\nt]balanc$1 ! c> c\ld desc5d1 its spe$ controll$ solely by ! brake4 ,! great popul>ity ( ?is novel sy/em app>5tly 0 due to its smoo? op]ation1 high spe$1 simplicity1 & economy ( op]ation4 ,manag$ by a skillful op]ator1 x 0 capable ( spe$s f> great] ?an o!r sy/ems c\ld !n a*ieve--up to a fright5+ #a1hjj feet p] m9ute4#f ,illu/ration3 ,figure #ab4--;,f9al developm5t ( ! ,baldw9-,hale wat] balance elevator1 #ahgc4 ,! brake1 kept appli$ by p[]ful spr+s1 0 releas$ only by /eady pressure on a lev]4 ,!re 7 two additional controls--! cont9u\s rope t op5$ ! ci/]n valve to fill ! bucket1 & a second lev] to op5 ! valve ( ! bucket to empty x4 7,f ,unit$ ,/ates ,railroad & ,m9+ ,regi/]1 ,apr4 #ab1 #ahgc1 vol4 #ag1 p4 #c47 ,9 addition to ! elem5t ( pot5tial dang] f c>eless op]ation or failure ( ! brake1 ! ,baldw9 sy/em 0 extremely exp5sive to in/all z a result ( ! second %aft1 :i* ( c\rse 0 requir$ to be m or less wat]tight4 ,mu* ( ! wat]-balance elevator's developm5t & ref9em5t 0 done by ,william ,e4 ,hale ( ,*icago1 :o also made mo/ ( ! in/allations4 ,! sy/em has1 !re=e1 come to be> 8 "n m commonly ?an ,baldw9's4 ,! popul>ity ( ! wat]-balance sy/em wan$ aft] only a few ye>s1 be+ eclips$ by m rational sy/ems4 ,hale ev5tually ab&on$ x & became ! we/]n ag5t = ,otis--by ?is "t prom95t 9 ! field--& subsequ5tly 0 influ5tial 9 developm5t ( ! hydraulic elevator4 ,! rope-ge>$ sy/em ( hydraulic elevator op]ation 0 s basically simple t by #ahhj x _h be5 embrac$ by virtually all manufactur]s4 ,h[ev]1 = ye>s mo/ build]s cont9u$ to ma9ta9 a l9e ( /eam & belt driv5 ma*9es = freight s]vice4 ,inspir$ by ! rapid increase ( tall] & tall] build+s1 !re 0 a conc5trat$ ef=t1 height5$ by sev]e competition1 to ref9e ! basic sy/em4 ,illu/ration3 ,figure #ac4--,v]tical cyl9d]1 rope-ge>$ hydraulic elevator ) #b3a ge> ratio & rope control 7ab\t #ahhj74 ,= high] rises & spe$s1 ratios ( up to #aj3a 7 us$1 & ! endless rope 0 replac$ by a lev]4 7,c\rtesy ( ,otis ,elevator ,company47 ,by ! late #ahhj's a va/ numb] ( improvem5ts 9 detail _h appe>$1 & ?is =m ( elevator 0 consid]$ to be almo/ )\t defect4 ,x 0 safe4 ,abs5ce ( a drum enabl$ ! c> to be c>ri$ by a numb] ( cables r ?an by "o or two1 & r5d]$ ov]travel impossible4 ,x 0 fa/4 ,control devices _h receiv$ probably ! mo/ att5tion by eng9e]s & 7 z p]fect & s5sitive z 0 possible ) me*anical means4 ,c>s ) lev] control c\ld be run at ! high spe$s requir$ = high build+s1 yet !y c\ld be /opp$ ) a smoo?ness & precision unatta9able e>li] ) sy/ems 9 :i* ! valves 7 controll$ by an endless rope1 work$ by ! op]ator4 ,x 0 almo/ completely sil5t1 & :5 ! cyl9d] 0 plac$ v]tically 9 a well ne> ! %aft1 practically no valuable floor space 0 occupi$4 ,b mo/ important1 ! l5g? ( rise 0 unlimit$ because no drum 0 us$4 ,z great] rises 7 requir$1 ! multiplication ( ! ropes & %eaves 0 simply increas$1 rais+ ! pi/on-c> travel ratio & p]mitt+ ! cyl9d] to rema9 ( manageable l5g?4 ,! ratio 0 (t5 z high z #aj or #ab to #a1 ! c> mov+ #aj or #ab feet to ! pi/on's #a4 ,9 addition to its pr9cipal advantages1 ! hydraulic elevator c\ld be op]at$ directly f municipal wat] ma9s 9 ! _m cities :]e !re 0 suffici5t pressure1 ?us elim9at+ a l>ge inve/m5t 9 tanks1 pumps & boil]s 7fig4 #ad74 ,by f> ! greate/ developm5t 9 ?is specializ$ bran* ( me*anical eng9e]+ occurr$ 9 ! ,unit$ ,/ates4 ,! comp>ative position ( ,am]ican practice1 :i* w be demon/rat$ f>!r on1 is indicat$ by ! fact t ,otis ,bro!rs & o!r l>ge elevator conc]ns 9 ! ,unit$ ,/ates 7 able to e/abli% (fices 9 _m ( ! major cities ( ,europe & compete v successfully ) local firms 9 spite ( ! high] co/s due to %ipm5t4 ,?is also demon/rates ! ext5t ( error 9 ! (t-he>d /atem5t t ! skyscrap] 0 ! direct result ( ! elevator's inv5tion4 ,!re is no "q t cont9u$ elevator improvem5t 0 an ess5tial factor 9 ! rapid increase ( build+ heights4 ,h[ev]1 consid]ation ( ! situation 9 ,european cities1 :]e build+s ( ov] #aj /ories 7 7& /ill are7 r>e 9 spite ( ! availability ( simil> elevator te*niques1 po9ts to ! fundam5tal matt] ( tradition4 ,! ,european city simply did n develop ) ! lack ( judicial re/ra9t :i* *>act]iz$ metropolitan gr[? 9 ! ,unit$ ,/ates4 ,! ,am]ican t5d5cy to conf9e m]cantile activity to ! smalle/ possible area result$ 9 excessive l& values1 :i* drove build+s skyw>d4 ,! elevator foll[$1 or1 at mo/1 kept pace )1 ! developm5t ( high] build+s4 ,illu/ration3 ,figure #ad4--;,9 ! v>i\s hydraulic sy/ems1 a pump 0 requir$ if pressure f wat] ma9s 0 insuffici5t to op]ate ! elevator directly4 ,!re 0 ei!r a gravity tank on ! ro( or a pressure tank 9 ! basem5t4 7,f ,?omas ,e4 ,br[n1 ,jr41 ,! ,am]ican ,pass5g] ,elevator1 ,eng9e]+ ,magaz9e 7,new ,york71 ,june #ahic1 vol4 #e1 p4 #cdj47 ,european elevator developm5t--not)/&+ ! numb] ( ,am]ican rope-ge>$ hydraulic ma*9es sold 9 ,europe 9 ! #aj ye>s or s prec$+ ! ,p>is fair ( #ahhi--0 conf9$ ma9ly to v>iations on ! direct plung] type1 :i* 0 fir/ us$ 9 ,engli% factories 9 ! #ahcj's4 ,! plung] elevator 7fig4 #af71 an ev5 clos] d]ivative ( ! hydraulic press ?an ,arm/rong's crane1 0 no?+ m ?an a plat=m on ! upp] end ( a v]tical plung] t rose f a cyl9d] z wat] 0 =c$ 94 ,!re 7 two reasons = ?is ,european practice4 ,! fir/ & mo/ app>5t 0 ! r>ity ( tall build+s4 ,! drill+ ( a well to receive ! cyl9d] 0 ?us a matt] ( little difficulty4 ,?is well _h to be equival5t 9 dep? to ! elevator rise4 ,! second reason 0 an innate ,european di/ru/ ( cable-hung elevator sy/ems 9 any =m1 an attitude t w be discuss$ m fully f>!r on4 ,,! ,,electric ,,elevator ,at ! "t ! ,eiffel ,t[] elevators 7 "u consid]ation1 wat] "u pressure 01 f a practical /&po9t1 ! only ag5t capable ( fulfill+ ! p[] & control requirem5ts ( ?is p>ticul>ly sev]e s]vice4 ,/eam1 z previ\sly m5tion$1 _h already be5 f\nd want+ 9 sev]al respects4 ,electricity1 on ! o!r h&1 seem$ to hold promise = almo/ e field ( human endeavor4 ,by #ahhh ! electric motor _h beh9d x a #aj- or #ae-ye> hi/ory ( active developm5t4 ,frank ,j4 ,sprague _h already plac$ 9 successful op]ation a sizable electric trolley-c> sy/em1 & 0 manufactur+ motors ( up to #bj horsep[] 9 comm]cial quantity4 ,light+ g5]ators 7 be+ produc$ 9 sizes f> great]4 ,!re 71 nev]!less1 _m ob/acles prev5t+ ! translation ( ?is progress into ma*9]y capable ( haul+ l>ge gr\ps ( p a v]tical di/ance ( #a1jjj feet ) unque/ionable dep5dability4 ,! fir/ application ( electricity to elevator propulsion 0 an exp]im5t ( ! di/+ui%$ ,g]man electrician ,w]n] von ,siem5s1 :o1 9 #ahhj1 con/ruct$ a c> t successfully climb$ a rack by means ( a motor & worm ge>+ b5ea? its deck 7figs4 #ag1 #ah7--;aga91 ! *>act]i/ic ,european di/ru/ ( cable susp5sion4 ,h[ev]1 ! effect ( ?is success on subsequ5t developm5t 0 negligible4 ,significant use ( electricity 9 ?is field occurr$ some:at lat]1 & 9 a mann] p>allel to t by :i* /eam 0 fir/ appli$ to ! elevator--! driv+ ( me*anical 7belt driv57 elevator ma*9es by individual motors4 ,slightly lat] came ano!r application ( ! conv]sion type4 ,?is 0 ! simple sub/itution ( electrically driv5 pumps 7fig4 #ba7 = /eam pumps 9 hydraulic in/allations4 ,x w be recall$ t pumps 7 necess>y 9 cases :]e wat] ma9 pressure 0 insuffici5t to op]ate ! elevator directly4 ,9 bo? ( ^! cases ! op]ational dem&s on ! motor 7 ( c\rse id5tical to ^? on ! prime mov]s :i* !y replac$2 no rev]sal ( direction 0 necess>y1 ! spe$ 0 con/ant1 & ! load 0 ne>ly con/ant4 ,fur!rmore1 ! load c\ld be appli$ to ! motor gradually ?r\gh automatic relief valves on ! pump & 9 ! me*anical ma*9es by slippage z ! belt 0 %ift$ f ! loose to ! fa/ pulleys4 ,! ultimate simplicity 9 control result$ f p]mitt+ ! motor to run cont9u\sly1 draw+ curr5t only 9 proportion to its load+4 ,! direct-curr5t motor ( ! #ahhj's 0 easily capable ( su* s]vice1 & x 0 widely us$ 9 ?is way4 ,illu/ration3 ,figure #ae4--,rope-ge>$ hydraulic freight elevator us+ a horizontal cyl9d] 7ab\t #ahhc74 7,f a ,lane ,bodley illu/rat$ catalog ( hydraulic elevators1 ,c9c9nati1 n4d47 ,illu/ration3 ,figure #af4--;,engli% direct plung] hydraulic elevator 7ab\t #ahie74 7,f ,f4 ,dye1 ,popul> ,eng9e]+1 ,london1 #ahie1 p4 #bhj47 ,adaptation ( ! motor to ! direct drive ( an elevator ma*9e 0 q ano!r matt]1 ! difficulties be+ l>gely ^? ( control4 ,at ?is "t ! only practical means ( />t+ a motor "u load 0 by introduc+ resi/ance into ! circuit & cutt+ x out 9 a s]ies ( /eps z ! spe$ pick$ up2 precisely ! me?od us$ to />t traction motors4 ,9 ! e>ly attempts to c\ple ! motor directly to ! w9d+ drum ?r\gh worm ge>+1 ?is not*+ up 0 transmitt$ to ! c> z a j]k+ motion1 disagreeable to pass5g]s & h>d on ma*9]y4 ,fur!rmore1 ! controll] contacts _h a %ort life because ( ! arc+ :i* result$ f heavy />t+ curr5ts4 ,9 all1 su* sy/ems 7 unsatisfactory & g5]ally unreliable1 & 7 held 9 disfavor by bo? elevator exp]ts & own]s4 ,illu/ration3 ,figure #ag4--,siem5s' electric rack-climb+ elevator ( #ahhj4 7,f ,w]n] von ,siem5s1 ,gesammelte ,abh&lung5 und ,vortrge1 ,b]l91 #ahha1 pl4 #e47 ,!re 01 moreov]1 little inducem5t to ov]come ! problem ( control & o!r m9or problems because ( a m s]i\s difficulty :i* _h p]si/$ s9ce ! days ( /eam4 ,?is 0 ! matt] ( ! drum & its att5dant limitations4 ,! motor's action be+ rotatory1 ! w9d+ drum 0 ! only practical way 9 :i* to apply its motive p[] to hoi/+4 ,?is s+le fact %ut electricity almo/ completely out ( any l>ge-scale elevator bus9ess until aft] ! turn ( ! c5tury4 ,true1 !re 0 a c]ta9 am\nt ( developm5t1 aft] ab\t #ahhg1 ( ! electric worm-drive drum ma*9e = sl[-spe$1 l[-rise s]vice 7fig4 #ai74 ,b ! fir/ in/allation ( ?is type t 0 consid]$ practically successful--9 t x 0 9 cont9u\s use = a long p]iod--0 n made until #ahhi1g ! ye> 9 :i* ! ,eiffel ,t[] 0 complet$4 ,p]t95t is ! "o ne>ly successful attempt :i* 0 made to approa* ! high-rise problem electrically4 ,9 #ahhh1 ,*>les ,r4 ,pratt1 an elevator eng9e] ( ,montclair1 ,new ,j]sey1 inv5t$ a ma*9e bas$ on ! horizontal cyl9d] rope-ge>$ hydraulic elevator1 9 :i* ! two sets ( %eaves 7 drawn ap>t by a screw & travel+ nut4 ,! screw 0 revolv$ directly by a ,sprague motor1 ! sy/em be+ kn[n z ! ,sprague-,pratt4 ,:ile a numb] ( in/allations 7 made1 ! ma*9e 0 subject to sev]al s]i\s me*anical faults & pass$ out ( use ar\nd #aijj4 ,g5]ally1 electricity z a practical workable p[] = elevators seem$ to hold little promise 9 #ahhh4h ,illu/ration3 ,figure #ah4--,motor & drive me*anism ( ,siem5s' elevator4 7,f ,alfr$ ,r4 ,urbanitzky1 ,electricity 9 ! ,s]vice ( ,man1 ,london1 #ahhf1 p4 #fdf47 ,illu/ration3 ,morse1 ,williams ,co41 ,,build]s ,,( ,,pass5g] ,,& ,,freight ,,elevators4 ,,electric ,,elevator4 ,write u = ,circul>s & ,prices4 ,ma9 ,(fice & ,works1 #aaje ,frank=d ,av5ue1 ,,philadelphia4 ,new ,york ,(fice1 #ajh ,lib]ty ,/reet4 ,new ,hav5 #hb ,*ur* ,/reet4 ,pittsburg #dac ,f\r? ,av5ue4 ,bo/on ,(fice #ai ,pe>l ,/reet4 ,baltimore ,build]s' ,ex*ange4 ,scranton #dbe ,spruce ,/reet4 ,figure #ai4--,! electric elevator 9 its e>lie/ comm]cial =m 7#ahia71 ) ! motor connect$ directly to ! load4 ,by ?is "t1 inc&esc5t light+ circuits 9 l>ge cities 7 suffici5tly ext5sive to make su* in/allations practical4 ,h[ev]1 capacity & lift 7 sev]ely limit$ by weaknesses ( ! control sy/em & ! necessity ( us+ a drum4 7,f ,electrical ,_w1 ,jan4 #b1 #ahig1 vol4 #bj1 p4 xcvii47 ,illu/ration3 ,,mill]',s ,,pat5t ,,life ,,& ,,labor-,,sav+ ,,screw ,,hoi/+ ,,ma*9e1 ,,= ,,! ,,use ,,( ,/ores1 ,hotels1 ,w>eh\ses1 ,factories1 ,sug> ,ref9]ies1 ,pack+ ,h\ses1 ,mills1 ,docks1 ,m9es1 c4 ,,manufactur$ ,,by ,,campbell1 ,,:itti] ,,co41 ,,roxbury1 ,,mass4 ,sole ,ag5ts = ! ,new ,engl& ,/ates4 ,! above ,engrav+ illu/rates a v sup]ior ,hoi/+ ,ma*9e1 design$ = ,/ore & ,w>eh\se ,hoi/+4 ,x is v simple 9 its con/ruction1 compact1 durable1 & n liable to get out ( ord]4 ,an exam9ation ( ! ,engrav+ w conv9ce any "o :o has any k ( ,ma*9]y1 t ! screw is ! only safe pr9ciple on :i* to con/ruct a ,hoi/+ ,ma*9e or ,elevator4 ,figure #bj4--;,adv]tisem5t = ! ,mill] screw-hoi/+ ma*9e1 ab\t #ahfg 7see p4 #bc74 ,f fly] 9 ! ,unit$ ,/ates ,national ,museum4 ,illu/ration3 ,figure #ba4--,! fir/ widespread use ( electricity 9 ! elevator field 0 to drive belt-type me*anical ma*9es & ! pumps ( hydraulic sy/ems 7see p4 #ad7 z %[n "h4 7,f ,electrical ,_w1 ,jan4 #d1 #ahij1 vol4 #ae1 p4 #d47 ,! ,t[]'s ,elevators ,a great "p ( ! ,eiffel ,t[]'s wor? & its raison d'tre lay 9 ! ov]:elm+ visual p[] by :i* x 0 to symbolize to a _w audi5ce ! sci5tific1 arti/ic1 &1 above all1 ! te*nical a*ievem5ts ( ! ,fr5* ,republic4 ,ano!r consid]ation1 9 ,eiffel's op9ion1 0 its great pot5tial value z a sci5tific obs]vatory4 ,at its summit gr& exp]im5ts & obs]vations w\ld be possible 9 su* fields z meteorology & a/ronomy4 ,9 ?is respect x 0 welcom$ z a trem5d\s improvem5t ov] ! balloon & /eam w9* t _h be5 featur$ 9 ?is s]vice at ! #ahgh ,p>is exposition4 ,exp]im5ts 7 also to be conduct$ on ! electrical illum9ation ( cities f great heights4 ,! great /rategic value ( ! ,t[] z an obs]vation po/ also 0 recogniz$4 ,b f ! beg9n+1 sight 0 nev] lo/ ( ! /ructure's great value z an unprec$5t$ public attraction1 & its sy/ematic exploitation 9 ?is mann] play$ a "p 9 its plann+1 second p]haps only to ! basic design4 ,! conveyance ( multitudes ( visitors to ! ,t[]'s fir/ or ma9 plat=m & a some:at less] numb] to ! summit 0 a te*nical problem ^: s]i\sness ,eiffel mu/ c]ta9ly h be5 aw>e ( at ! project's onset4 ,:ile a few visitors c\ld be expect$ to walk to ! fir/ or possibly second /age1 #cgg feet above ! gr\nd1 ! ma9 means ( transport obvi\sly _h to be elevators4 ,inde$1 ! two aspects ( ! ,t[] ) :i* ! ,exposition commission]s 7 mo/ deeply conc]n$ 7 ! adequate gr\nd+ ( lightn+ & ! provision ( a reliable sy/em ( elevators1 :i* !y insi/$ be unconditionally safe4 ,to /udy ! elevator problem1 ,eiffel reta9$ a man nam$ ,backmann :o 0 consid]$ an exp]t on ! subject4 ,app>5tly ,backmann orig9ally 0 to design ! complete sy/em1 b he 0 to prove inadequate to ! task4 ,z 8 few s*emes are /udi$ x becomes increas+ly difficult to imag9e by :at qualifications he 0 reg>d$ z ei!r an elevator exp]t or design] by ,eiffel & ! ,commission4 ,8 proposals appe>1 ) "o exception1 to h be5 decid$ly retrogressive1 &1 fur!r1 to incorporate ! mo/ undesirable features ( ^? e>li] sy/ems he *ose to borr[ f4 ,no?+ has be5 discov]$ reg>d+ 8 "w1 if any1 on elevators = ! l[] section ( ! ,t[]4 ,realiz+ ! difficulty ( ?is aspect ( ! problem1 he may n h attempt$ its solution1 & conf9$ 8 "w to ! upp] half :]e ! /ructure p]mitt$ a /raight1 v]tical run4 ,illu/ration3 ,figure #bb4--,v>i\s levels ( ! ,eiffel ,t[]4 7,adapt$ f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 pl4 #a47 ,! ,backmann design = ! upp] elevators 0 bas$ ^u a pr9ciple :i* _h be5 attractive to _m inv5tors 9 ! mid-#ai? c5tury p]iod ( elevator developm5t--t ( screw+ ! c> up by means ( a ?read$ elem5t & a nut1 ei!r ( :i* might be rotat$ & ! o!r rema9 /ation>y4 ,! analogy to a nut & bolt made ! s*eme an obvi\s "o at t e>ly "t1 b its inh]5t complexity soon became equally evid5t & x nev] a*iev$ practical success4 ,backmann project$ two cyl9drical c>s t travel$ 9 p>allel %afts & balanc$ "o ano!r f opposite ends ( common cables t pass$ ov] a %eave 9 ! upp]works4 ,ar\nd ! inside ( ea* %aft ext5d$ a spiral track ^u :i* ran roll]s atta*$ to revolv+ frames und]nea? ! c>s4 ,:5 ! frames 7 made to revolve1 ! roll]s1 runn+ ar\nd ! track1 w\ld raise or l[] "o c>1 ! o!r travel+ 9 ! opposite direction 7fig4 #bc74 ,illu/ration3 ,figure #bc4--;,backmann's propos$ helicoidal elevator = ! upp] section ( ! ,eiffel ,t[]4 ,! c>s 7 to be self-p[]$ by electric motors4 ,note simil>ity to ! ,mill] sy/em 7fig4 #bj74 7,adapt$ f ,! ,eng9e] 7,london71 ,aug4 #c1 #ahhh1 vol4 #ff1 p4 #aja47 ,9 ! plan z fir/ pres5t$1 a gr\nd-bas$ /eam eng9e drove ! frames & roll]s ?r\gh an endless fly rope--travel+ at high spe$ presumably to p]mit x to be ( small diamet] & /ill transmit a reasonable am\nt ( p[]--:i* engag$ pulleys on ! c>s4 ,! design 0 rem>kably simil> to t ( ! ,mill] ,pat5t ,screw ,hoi/+ ,ma*9e1 :i* _h _h a brief life 9 ! ,unit$ ,/ates ar\nd #ahfe4 ,! ,mill] sy/em 7see p4 #ai7 us$ a flat belt r ?an a rope 7fig4 #bj74 ,?is plan 0 quickly reject$1 probably because ( anticipat$ difficulties ) ! rope transmission4#i ,backmann's second proposal1 actually approv$ by ! ,commission1 incorporat$ ! only--al?\gh highly significant--innovation evid5t 9 8 designs4 ,= ! rope transmission1 electric motors 7 sub/itut$1 "o 9 ea* c> to drive ! roll] frame directly4 ,) ?is modification1 ! plan does n seem q z unreasonable1 & w\ld probably h work$4 ,h[ev]1 x w\ld c]ta9ly h lack$ ! necess>y durability & w\ld h be5 extremely exp5sive4 ,! ,commission disc>d$ ! :ole s*eme ab\t ! middle ( #ahhh1 giv+ two reasons = its action3 7#a7 ! novelty ( ! sy/em & ! att5dant possibility ( /oppages :i* might s]i\sly int]rupt ! exploitation ( ! ,t[]1 & 7#b7 fe> t ! roll]s runn+ ar\nd ! tracks w\ld cause excessive noise & vibration4 ,bo? reasons seem q incr$ible :5 ! ,backmann sy/em is comp>$ to "o ( ^? actually us$--! ,r\x1 describ$ bel[--:i* obvi\sly mu/ h be5 subject to id5tical fail+s1 & on a f> great] scale4 ,m likely !re exi/$ an unspok5 di/ru/ ( electric propulsion4 ,t ! ,backmann sy/em %\ld h be5 giv5 s]i\s consid]ation at all reflects ! unc]ta9ty surr\nd+ ! entire matt] ( provid+ elevator s]vice ( su* unusual nature4 ,_h ! ,eiffel ,t[] be5 erect$ only #ae ye>s lat]1 ! situation w\ld h be5 simply "o ( selection4 ,z x 01 ,eiffel & ! commission]s 7 gov]n$ n by :at !y want$ b l>gely by :at 0 available4 ,,! ,,otis ,,sy/em ,! curvature ( ! ,t[]'s legs impos$ a problem unique 9 elevator design1 & x caus$ great annoyance to ,eiffel1 ! fair's ,commission1 & all o!rs conc]n$4 ,s9ce a v]tical %aftway any:]e )9 ! op5 area b5ea? ! fir/ plat=m 0 e/hetically un?9kable1 ! elevators c\ld be plac$ only 9 ! incl9$ legs4 ,! problem ( rea*+ ! fir/ plat=m 0 n s]i\s4 ,! legs 7 wide en\gh & _! curvature s slight 9 ?is l[] portion z to p]mit !m to conta9 a /raight run ( track1 & ! s]vice c\ld h be5 design$ along ! l9es ( an ord9>y incl9$ railway4 ,x 0 e/imat$ t ! great majority ( visitors w\ld g only to ?is level1 attract$ by ! sev]al int]national re/aurants1 b>s & o!r features locat$ !re4 ,two elevators to op]ate only t f> 7 contract$ = ) no difficulty--"o to be plac$ 9 ! ea/ leg & "o 9 ! we/4 ,to transport p to ! second plat=m 0 an altoge!r diff]5t problem4 ,s9ce !re 0 to be a s+le run f ! gr\nd1 x w\ld h be5 necess>y to =m ! elevator guides ei!r ) a con/ant curvature1 approximat+ t ( ! legs1 or ) a s]ies ( /raight *ords connect$ by %ort segm5tal curves ( small radius4 ,eiffel plann$ initially to use ! fir/ me?od1 b ! second 0 adopt$ ultimately1 probably z be+ ! simpl] because only two /raight l5g?s ( run 7 f\nd to be necess>y4 ,bids 7 invit$ = two elevators on ?is basis--"o ea* = ! nor? & s\? legs4 ,"h ! unprec$5t$ "* ( ! matt] became evid5t--!re 0 n a firm 9 ,france will+ to und]take ! "w4 ,! ,am]ican ,elevator ,company1 ! ,european bran* ( ,otis ,bro!rs ,company1 did submit a proposal ?r\gh its ,p>is (fice1 ,otis ,asc5seur ,cie41 b ! ,commission 0 compell$ to reject x because a clause 9 ! fair's *>t] prohibit$ ! use ( any =eign mat]ial 9 ! con/ruction ( ! ,t[]4 ,fur!rmore1 !re 0 a /rong prejudice aga9/ =eign contractors1 :i*1 because ( ! g5]al backgr\nd ( disfavor surr\nd+ ! project dur+ its e>ly /ages1 0 an elem5t wor? s]i\s consid]ation by ! ,commission4 ,! bidd+ "t 0 ext5d$1 & _m attempts 7 made to attract a native design b none 0 =?com+4 ,z "t grew %ort1 x became imp]ative to resolve ! matt]1 & ! ,commission1 9 desp]ation1 aw>d$ ! contract to ,otis 9 ,july #ahhg = ! am\nt ( #bb1ejj4aj ,a curi\s footnote to ! affair appe>$ mu* lat] 9 ! =m ( a publi%$ int]view#aa ) ,w4 ,frank ,hall1 ,otis' ,p>is repres5tative3 ,yes1 said ,mr4 ,hall1 ?is is ! fir/ elevator ( its k9d4 ,our p = ?irty-eight ye>s h be5 do+ ?is "w1 & h con/ruct$ ?\s&s ( elevators v]tically1 & _m on an incl9e1 b nev] "o to /rike a radius ( #afj feet = a di/ance ( ov] #ej feet4 ,x has requir$ a great am\nt ( prep>atory /udy & we h work$ on x = ?ree ye>s4 ,t 0 be=e y got ! contract8 ,q s1 b we knew t1 al?\gh ! ,fr5* au?orities 7 v reluctant to give away ?is piece ( "w1 !y w\ld be b\nd to come to u1 & s we 7 prep>+ = !m4 ,su* supreme confid5ce mu/ h rapidly evaporat$ z ev5ts progress$4 ,despite ! invaluable adv]tis+ to be d]iv$ f an in/allation ( su* di/9ction1 ! ,otises w\ld probably h default$ _h !y =ese5 ! difficulties :i* prec$$ completion ( ! "w4 ,illu/ration3 ,figure #bd4--;,g5]al arrangem5t ( ,otis elevator sy/em 9 ,eiffel ,t[]4 7,f ,! ,eng9e] 7,london71 ,july #ai1 #ahhi1 vol4 #fh1 p4 #eh47 ,! propos$ sy/em 7fig4 #bd7 0 bas$ fundam5tally ^u ,otis' /&>d hydraulic elevator1 b x 0 recognizable only 9 basic op]at+ pr9ciple 7fig4 #be74 ,tracks ( regul> rail section replac$ ! guides because ( ! incl9e1 & ! d\ble-deck$ cab9 7fig4 #bi7 ran on small flang$ :eels4 ,?is mu* ( ! app>atus 0 really n unlike t ( an ord9>y incl9$ railway4 ,motive p[] 0 provid$ by ! cu/om>y hydraulic cyl9d] 7fig4 #bf71 set on an angle r\ghly equal to ! incl9e ( ! l[] section ( run4 ,balanc+ ! cab9's dead weight 0 a c\nt]poise c>riage 7fig4 #bg7 load$ ) pig iron t travel$ on a second set ( rails b5ea? ! ma9 track4 ,l ! driv+ sy/em1 ! c\nt]weight 0 rope-ge>$1 #c to #a1 s t its travel 0 ab\t #abe feet to ! cab9's #cgg feet4 ,illu/ration3 ,figure #be4--,s*ematic diagram ( ! rigg+ ( ! ,otis sy/em4 7,adapt$ f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 p4 #abg47 ,ev]y?+ ab\t ! sy/em 0 on a scale f> heavi] ?an f\nd 9 ! normal elevator ( ! type4 ,! cyl9d]1 ( #ch-;in* bore1 0 #cf feet long4 ,r ?an a simple ne/ ( pulleys1 ! pi/on rods pull$ a l>ge guid$ c>riage or *>iot be>+ six movable %eaves 7fig4 #bh74 ,correspond+ 7 five /ation>y %eaves1 ! :ole reev$ to =m an imm5se #ab-pur*ase tackle4 ,! c>1 atta*$ to ! free ends ( ! cables1 0 haul$ up z ! pi/on drew ! two %eave assemblies ap>t4 ,9 exam9+ ! sy/em1 x is difficult to det]m9e :at s+le elem5t 9 its design might h caus$ su* a problem z to h be5 beyond ! eng9e]+ ability ( a ,fr5* firm1 & to h caus$ su* conc]n to a l>ge1 well-e/abli%$ ,am]ican organization ( ,otis' wide elevator & incl9$ railway exp]i5ce4 ,inde$1 :5 ! ,fr5* sy/em--:i* s]v$ ! fir/ plat=m f ! ea/ & we/ legs--is exam9$1 x appe>s curi\s t a national te*nology capable ( produc+ a ma*9e at su* a level ( complexity %\ld h be5 unable to deal easily ) ! entire matt]4 ,?is c be plausibly expla9$ only on ! basis ( ,europe's previ\sly m5tion$ lack ( exp]i5ce ) rope-ge>$ & o!r cable-hung elevator sy/ems4 ,! difficulty att5d+ ,otis' "w1 usually true 9 ! case ( all innovations1 lay unque/ionably 9 ! multitudes ( details--_m ( !m1 ( c\rse1 invisible :5 only ! successfully work+ end product is obs]v$4 ,m ?an a matt] ( detail 0 ! ,commission's dem& = p]fect safety1 :i* precipitat$ a situation typical ( _m confront+ ,otis dur+ ! entire "w4 ,otis _h wi%$ to coord9ate ! entire design process ?r\gh ,mr4 ,hall1 ) te*nical matt]s h&l$ by mail4 ,nev]!less1 at ,eiffel's insi/5ce1 & ) "s inconv5i5ce1 9 #ahhh ! company dispat*$ ! project's eng9e]1 ,?omas ,e4 ,br[n1 ,jr41 to ,p>is = a direct consultation4 ,mild conflict ov] m9or details ensu$1 b a gross diff]5ce ( op9ion arose ultimately betwe5 ! ,am]ican & ,fr5* eng9e]s ov] ! safety ( ! sy/em4 ,! disagreem5t ?reat5$ to halt ! entire project4 ,9 common ) all elevators 9 :i* ! c> hangs by cables1 ! prime consid]ation "h 0 a means ( arre/+ ! cab9 %\ld ! cables fail4 ,z orig9ally pres5t$ to ,eiffel1 ! plans indicat$ an elaborate modification ( ! /&>d ,otis safety device--itself a direct d]ivative ( ,e4 ,g4 ,otis' orig9al4 ,if any "o ( ! six hoi/+ cables broke or /ret*$ unduly1 or if _! t5sion slack5$ = any reason1 p[]ful leaf spr+s 7 releas$ caus+ brake %oes to grip ! rails4 ,! ess5tial feature ( ! design 0 ! c>'s arre/ by friction betwe5 its gripp]s & ! rails s t ! /opp+ action 0 gradual1 n sudd5 z 9 ! elevator safety4 ,dur+ pro( trials ( ! safety1 made prior to ! fair's op5+ by cutt+ away a set ( tempor>y hoi/+ cables1 ! cab9 w\ld fall ab\t #aj feet be=e be+ halt$4 ,illu/ration3 ,figure #bf4--,section ?r\gh ! ,otis p[] cyl9d]4 7,adapt$ f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 pl4 #bb47 ,illu/ration3 ,figure #bg4--;,details ( ! c\nt]weight c>riage 9 ! ,otis sy/em4 7,f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 pl4 #bbd47 ,al?\gh highly effici5t & ( unque/ionable security1 ?is safety device 0 consid]$ an insuffici5t safegu>d by ,eiffel1 :o1 speak+ 9 ! "n ( ! ,commission1 dem&$ ! application ( a device kn[n z ! rack & p9ion safety t 0 us$ to "s ext5t on ,european cog railways4 ,! commission]s n only consid]$ ?is sy/em m reliable b felt t "o ( its features 0 a necessity3 a device t p]mitt$ ! c> to be l[]$ by h&1 ev5 aft] failure ( all ! hoi/+ cables4 ,! s]i\s %ortcom+s ( ! rack & p9ion 7 its great nois9ess & ! limitation x impos$ on hoi/+ spe$4 ,bo? disadvantages 7 due to ! con/ant engagem5t ( a p9ion on ! c> ) a cont9u\s rack set betwe5 ! rails4 ,! meet+ end$ 9 an impasse1 ) ,br[n unwill+ to approve ! objectionable app>atus & able only to return to ,new ,york & lay ! matt] be=e 8 company4 ,:ile ,eiffel's attitude 9 ! matt] may appe> highly unreasonable1 x mu/ be said t dur+ a subsequ5t meet+ betwe5 ,br[n & ,koe*l91 ! ,fr5* eng9e] impli$ t a mutual antagonism _h aris5 betwe5 ! ,t[]'s creator & ! ,commission4 ,?us1 s9ce 8 own judgm5t mu/ h _h little influ5ce ) ! commission]s at t "t1 ,eiffel 0 compell$ to specify :at he well knew 7 excessive safety provisions4 ,?is decision plac$ ,otis ,bro!rs 9 a decid$ly uncom=table position1 at ! m]cy ( ! ,commission4 ,w4 ,e4 ,hale1 promot] ( ! wat] balance elevator--:o by !n _h a /rong voice 9 ,otis' affairs--express$ ! s]i\sness ( ! matt] 9 a lett] to ! company's presid5t1 ,*>les ,r4 ,otis1 foll[+ receipt ( ,br[n's report on ! ,p>is conf]5ce4 ,ref]r+ to ! controv]sial cog:eel1 ,hale wrote 444 if ?is mu/ be arrang$ s t ! c> is effect$ sic 9 its op]ation by con/ant contact ) ! rack & p9ion 444 s z to communicate ! noise & j>1 & unpleasant motion :i* su* an arrangem5t always produces1 ,i %\ld favor giv+ up ! :ole matt] r ?an ally+ ourselves ) any su* abortion4444 we w\ld be ! laugh+ /ock ( ! _w1 = putt+ up su* a contrivance4 ,?is difficult situation app>5tly 0 ! product ( a some:at g5]al contract phras$ 9 t]ms ( s]vice to be provid$ r ?an ( specific equipm5t to be us$4 ,?is is n unusual1 b x did leave op5 to lat] dispute su* ambigu\s clauses z adequate safety devices are to be provid$4 ,al?\gh fac$ ) ! loss n only ( all previ\sly exp5d$ design "w b also ( an adv]tisem5t ( int]national consequ5ce1 ! company app>5tly concurr$ ) ,hale & s advis$ ,p>is4 ,un=tunately1 !re are no ,otis records to reveal ! subsequ5t transactions1 b we may assume t ,otis' ?reat ( )drawal prevail$1 c\pl$ z x 0 ) ,eiffel's confid5ce 9 ! ,am]ican equipm5t4 ,! sy/em w5t into op]ation z orig9ally design$1 free ( ! odi\s rack & p9ion4 ,t1 un=tunately1 0 n ! f9al disagreem5t4 ,be=e ! fair's op5+ 9 ,may #ahhi1 ! relation%ip 0 /ra9$ s dra/ically t a mutually satisfactory conclusion to ! project mu/ inde$ h seem$ hopeless4 ,! num]\s m9or /ructural modifications ( ! ,t[] legs f\nd necess>y z con/ruction progress$ _h necessitat$ c]ta9 equival5t alt]ation to ! ,otis design ins(> z its dep5d5cy ^u ! framework 0 affect$4 ,consequ5tly1 "w on ! ma*9]y 0 set back by "s mon?s4 ,eiffel 0 in=m$ t al?\gh ev]y?+ 0 gu>ante$ to be 9 full op]ation by op5+ day on ,may #a1 ! contractual deadl9e ( ,janu>y #a c\ld n possibly be met4 ,eiffel1 n[ unque/ionably act+ on 8 own volition1 respond$ by cable1 refus+ all paym5t4 ,*>les ,otis' reply1 a classic ( indignation1 disclos$ to ,eiffel ! jeop>dy 9 :i* 8 impetuosity _h plac$ ! success ( ! entire project3 ,aft] all else we h borne & suff]$ & a*iev$ 9 y\r behalf1 we reg>d ?is z a trifle too mu*2 & we d n hesitate to decl>e1 9 ! /ronge/ t]ms possible to ! ,engli% language1 t we w n put up ) x 444 &1 if !re is to be ,w>1 "u ! exi/+ circum/ances1 propose t at lea/ "p ( x %all be f\ght on ,am]ican gr\nd4 ,if ,mr4 ,eiffel %all1 on ! contr>y1 treat u z we believe we are entitl$ to be treat$1 "u ! circum/ances1 & 8 confid5ce 9 our integrity to s]ve him well %all be re/or$ 9 season to admit ( ! completion ( ?is "w at ! "t want$1 well & good2 b x mu/ be done at once 444 o!rwise we %all %ip no m "w f ?is side1 & ,mr4 ,eiffel mu/ *>ge to himself ! consequ5ces ( 8 own acts4 ,?is message app>5tly _h ! desir$ effect & ! matt] 0 someh[ resolv$1 z ! ma*9]y 0 9 full op]ation :5 ! ,exposition op5$4 ,! in/allation mu/ h _h imm5se promotional value = ,otis ,bro!rs1 p>ticul>ly 9 its contra/ to ! some:at anomal\s ,fr5* sy/em4 ,?is contra/ evid5tly 0 visible to ! te*nically unsophi/icat$ z well z to visit+ eng9e]s4 ,sev]al newspap]s report$ t ! ,otis elevators 7 "o ( ! be/ ,am]ican exhibits at ! fair4 ,9 spite ( _! l>ge ov]-all scale & ! complication ( ! basic patt]n impos$ by ! unique situation1 ! ,otis elevators p]=m$ well & ju/ifi$ ! orig9al judgm5t & confid5ce :i* _h prompt$ ,eiffel to fight = _! in/allation4 ,aside f ! obvi\s advantage ( simplicity :5 comp>$ to ! ,fr5* ma*9es1 _! op]ation 0 relatively quiet1 & fa/4 ,! d\ble c>1 travel+ at #djj feet p] m9ute1 c>ri$ #dj p]sons1 all seat$ because ( ! *ange ( incl9ation4 ,! ma9 valve or di/ributor t controll$ ! fl[ ( wat] to & f ! driv+ cyl9d] 0 op]at$ f ! c> by cables4 ,! hydraulic head necess>y to produce pressure )9 ! cyl9d] 0 obta9$ f a l>ge op5 res]voir on ! second plat=m4 ,aft] be+ exhau/$ f ! cyl9d]1 ! wat] 0 pump$ back up by two ,gir>d pumps 7fig4 #ca7 9 ! eng9e room at ! base ( ! ,t[]'s s\? leg4 ,,! ,,sy/em ,,( ,,r\x1 ,,combaluzi] ,,& ,,lepape ,!re c be little d\bt t ! ,fr5* elevators plac$ 9 ! ea/ & we/ pi]s to c>ry visitors to ! fir/ /age ( ! ,t[] _h ! important second>y function ( sav+ face4 ,t an eng9e] ( ,eiffel's me*anical p]ception w\ld h p]mitt$ _! use1 unless compell$ to d s by ! ,exposition ,commission1 is un?9kable4 ,:atev] ! attitudes ( ! commission]s may h be51 x mu/ be said--recall+ ! ,backmann sy/em--t !y did n fe> innovation4 ,! ma*9]y in/all$ by ! firm ( ,r\x1 ,combaluzi] & ,lepape 0 novel 9 e respect1 b x 0 a product ( misguid$ +5uity & set no prec$5t4 ,! sy/em1 nev] duplicat$1 0 conceiv$1 born1 liv$ a brief & n ov]ly cr$itable life1 & di$1 entirely )9 ! ,t[]4 ,basis ( ! ,fr5* sy/em 0 an endless *a9 ( %ort1 rigid1 articulat$ l9ks 7fig4 #ce71 to "o po9t ( :i* ! c> 0 atta*$4 ,z ! *a9 mov$1 ! c> 0 rais$ or l[]$4 ,recall+ ! ,european di/ru/ ( susp5d$ elevators1 x is int]e/+ to note t ! c> 0 pu%$ up by ! l9ks bel[1 n drawn by ^? above1 ?us ! active l9ks 7 9 compression4 ,to prev5t buckl+ ( ! column1 ! *a9 0 enclos$ 9 a conduit 7fig4 #cf74 ,excessive friction 0 prev5t$ by a pair ( small roll]s at ea* ( ! knuckle jo9ts betwe5 ! l9ks4 ,! sy/em 01 9 fact1 a duplicate "o1 ) a *a9 on ei!r side ( ! c>4 ,at ! bottom ( ! run ! *a9s pass$ ar\nd huge sprocket :eels1 #ab4hj feet 9 diamet]1 ) pockets on _! p]iph]ies to engage ! jo9ts4 ,small] :eels at ! top guid$ ! *a9s4 ,if by "s motive =ce ! :eel 7fig4 #cc7 7 turn$ c\nt]clockwise1 ! l[] half ( ! *a9 w\ld be driv5 upw>d1 c>ry+ ! c> ) x4 ,slots on ! inside faces ( ! l[] guide trunks p]mitt$ passage ( ! connection betwe5 ! c> & *a94 ,lead weights on c]ta9 l9ks ( ! *a9s' upp] or return sections c\nt]balanc$ mo/ ( ! c>'s dead weight4 ,illu/ration3 ,figure #bh4--,plan & section ( ! ,otis sy/em's movable pulley assembly1 or *>iot4 ,pi/on rods are at left4 7,adapt$ f ,! ,eng9e] 7,london71 ,july #ai1 #ahhi1 vol4 #fh1 p4 #eh47 ,two horizontal cyl9d]s rotat$ ! driv+ sprockets ?r\gh a me*anism ^: effect 0 simil> to ! rope-ge>+ ( ! /&>d hydraulic elevator1 b :i* might be describ$ z *a9 ge>+4 ,! cyl9d]s 7 ( ! pu%+ r ?an ! pull+ type us$ 9 ! ,otis sy/em2 t is1 ! pressure 0 introduc$ beh9d ! plung]s1 driv+ !m out4 ,to ! ends ( ! plung]s 7 fix$ smoo?-fac$ %eaves1 ov] :i* 7 loop$ heavy quadruple-l9k pit* *a9s1 "o end ( ea* be+ solidly atta*$ to ! ma*9e base4 ,! free ends ran "u ! cyl9d] & made ano!r half-wrap ar\nd small sprockets key$ to ! ma9 drive %aft4 ,z ! plung]s 7 =c$ outw>d1 ! free ends ( ! *a9 mov$ 9 ! opposite direction1 at twice ! velocity & l9e> displacem5t ( ! plung]s4 ,! drive sprockets 7 !reby revolv$1 driv+ up ! c>4 ,desc5t 0 made simply by p]mitt+ ! cyl9d]s to exhau/1 ! c> dropp+ ( its own weight4 ,! ov]-all ge> or ratio ( ! sy/em 0 ! multiplication due to ! d\ble pur*ase ( ! plung] %eaves times ! ratio ( ! *a9 & drive sprocket diamet]s3 #b7ab4hj_/a4ig7 or ab\t #ac3a4 ,to drive ! c> #bah feet to ! fir/ plat=m ( ! ,t[] ! plung]s travel$ only ab\t #af4e feet4 ,to p5etrate ! inv5tive rationale beh9d ?is /range ma*9e is n difficult4 ,aw>e ( ! fundam5tal dictum ( absolute safety be=e all else1 ! ,r\x eng9e]s turn$ logically to ! safe/ kn[n elevator type--! direct plung]4 ,?is type ( elevator1 be+ well suit$ to l[ rises1 =m$ ! ma9 body ( ,european practice at ! "t1 & 9 ?is fact lay ! fur!r attraction ( a sy/em firmly bas$ on tradition4 ,s9ce ! pi]s betwe5 ! gr\nd & fir/ plat=m c\ld accommodate a /raight1 al?\gh incl9$ run1 ! solution might obvi\sly h be5 to use an incl9$1 direct plung]4 ,! only difficulty w\ld h be5 t ( drill+ a #bbj-;foot1 incl9$ well = ! cyl9d]4 ,:ile a difficult problem1 x w\ld n h be5 insurm\ntable4 ,:at !n 0 ! reason = us+ a design va/ly m complex8 ,! only reasonable answ] t pres5ts itself is t ! design]s1 work+ 9 a p]iod be=e ! ,otis bid _h be5 accept$1 7 attempt+ to evolve an app>atus capable ( ! complete s]vice to ! second plat=m4 ,! use ( a rigid direct plung] ?us preclud$1 x became necess>y to transpose ! basic idea 9 ord] to adapt x to ! curvature ( ! ,t[] leg1 & at ! same "t reta9 its inh]5t quality ( safety4 ,cont9u+ ! conceptual sequ5ce1 ! idea ( a plung] made 9 "s mann] flexible app>5tly sugge/$ itself1 becom+ ! he>t ( ! ,r\x ma*9es4 ,illu/ration3 ,figure #bi4--,section ?r\gh cab9 ( ! ,otis elevator4 ,note ! pivot$ floor-sections4 ,z ! c> travel$1 ^! floor-sections 7 level$ by ! op]ator to comp5sate = ! *ange ( incl9ation2 h[ev]1 !y 7 soon remov$ because !y int]f]$ ) ! load+ & unload+ ( pass5g]s4 7,f ,la ,nature1 ,may #d1 #ahhi1 vol4 #ag1 p4 #cfj47 ,"h !n 0 a design exhibit+ /range contra/4 ,x 0 on ! "o h& completely novel1 devis$ expressly = ?is try+ s]vice2 yet on ! o!r h& x 0 d]iv$ f & fundam5tally bas$ on a ?or\ghly traditional sy/em4 ,if no?+ else1 x 0 safe beyond "q4 ,9 ,eiffel's own words1 ! ,r\x lifts n only 7 safe1 b appe>$ safe2 a mo/ desirable feature 9 lifts travel+ to su* heights & c>ry+ ! g5]al public4#ab ,! sy/em's %ortcom+s c\ld h>dly be m evid5t4 ,friction result+ f ! m ?an #cbj jo9ts 9 ! flexible pi/ons1 ea* c>ry+ two roll]s1 plus t f ! pit* *a9s mu/ h be5 imm5se4 ,! noise creat$ by su* multiplicity ( p>ts c only be imag9$4 ,capacity 0 equival5t to t ( ! ,otis sy/em4 ,ab\t #ajj p c\ld be c>ri$ 9 ! d\ble-deck cab91 "s /&+4 ,! spe$1 h[ev]1 0 only #bjj feet p] m9ute1 und]/&ably l[4 ,if x _h be5 ! initial int5tion ( ! design]s to op]ate _! c>s to ! second plat=m1 !y mu/ %ortly h become aw>e ( ! impracticability ( ?is plan1 caus$ by an inh]5t *>act]i/ic ( ! app>atus4 ,z long z ! compressive =ce act$ along ! longitud9al axis ( ! l9ks1 !re 0 no lat]al resultant & ! only load on ! small roll]s 0 t due to ! dead weight ( ! l9k itself4 ,h[ev]1 if a curve _h be5 introduc$ 9 ! guide *annels to increase ! incl9e ( ! upp] run1 z done by ,otis1 ! =ce on ^? l9ks trav]s+ ! b5d w\ld h be5 ecc5tric--assum+ ! c> to be 9 ! upp] section1 above ! b5d4 ,! diff]5ce betwe5 ! two sections 7bas$ ^u ! ,otis sy/em7 0 #ghi' m9us #edce'1 or #bccd'1 ! tang5t ( :i* equals #j4dcf4 ,=ty-?ree p]c5t ( ! unbalanc$ weight ( ! c> & load w\ld !n h borne ^u !1 say1 #ab sets ( roll]s on ! curve4 ,! imm5se frictional load ?us add$ to ! entire sy/em w\ld c]ta9ly h made x dismally ineffici5t1 if n actually unworkable4 ,9 spite ( ,eiffel's public rem>ks reg>d+ ! safety ( ! ,r\x ma*9]y1 9 private he did n tr\ble to conceal 8 d\bts4 ,otis' repres5tative1 ,hall1 discuss+ ?is t[>d ! end ( ,br[n's previ\sly m5tion$ report1 probably pres5t$ a fairly accurate picture ( ! situation4 ,8 comm5ts 7 bas$ on conv]sations ) ,eiffel & ,koe*l93 ,mr4 ,gibson1 ,mr4 ,hann+ :o 7 o!r ,otis employees & myself came to ! unanim\s conclusion t ,mr4 ,eiffel _h be5 =c$ to ord] ^? o!r ma*9es1 f outside p>ties1 aga9/ 8 own judgm5t3 & t he 0 v mu* 9 d\bt z to _! be+ a practical success--& 01 !re=e1 all ! m anxi\s to put 9 our ma*9es 7:i* he did h fai? 97 444 & if ! o!rs ate up coal 9 proportions greatly 9 excess ( ours1 he w\ld h x to say 444 ,g5tlem51 ^! are my *oice ( elevators1 ^? are y\rs c4 ,!re 0 a publi%$ int]view 444 9 :i* ,eiffel /at$ 444 t he 0 to meet "s ,am]ican g5tlem5 ! foll[+ day1 :o 7 to provide him ) elevators--gr& elevators1 ,i ?9k he said4444 ,illu/ration3 ,figure #cj4--,upp]works & pass5g] plat=ms ( ! ,otis sy/em at second level4 7,f ,la ,nature1 ,aug4 #aj1 #ahhi1 vol4 #ag1 p4 #afi47 ,! ,r\x & ! ,otis sy/ems bo? drew _! wat] supply f ! same tanks2 also1 ea* sy/em us$ simil> di/ribut+ valves 7fig4 #cb7 op]at$ f ! c>s4 ,al?\gh no reports h be5 f\nd ( actual controll$ te/s comp>+ ! effici5cies ( ! ,otis & ,r\x sy/ems1 a g5]al quantitative comp>ison may be made f ! balance figures giv5 = ea* 7p4 #dj71 :]e x is se5 t #b1ffe p\nds ( excess tractive ef=t 7 all[$ to ov]come ! friction ( ! ,otis ma*9]y aga9/ #ac1hef p\nds = ! ,r\x4 ,,! ,,ed\x ,,sy/em ,! section ( ! ,t[] pres5t+ ! lea/ difficulty to elevator in/allation 0 t above ! juncture ( ! f\r legs--f ! second plat=m to ! ?ird1 or obs]vation1 enclosure4 ,!re 0 no "q t ,fr5* equipm5t c\ld p]=m ?is s]vice4 ,! run be+ p]fectly /raight & v]tical1 ! only unusual dem& ^u contempor>y elevator te*nology 0 ! l5g? ( rise--#ebe feet4 ,! sy/em ultimately select$ 7fig4 #cg7 appeal$ to ! ,commission l>gely because ( a simil> "o t _h be5 in/all$ 9 "o t[] ( ! fam\s ,trocad]o#ac & :i* _h be5 op]at+ successfully = #aj ye>s4 ,x 0 ! direct plung] sy/em ( ,leon ,ed\x1 & 01 = ! "t1 f> m rationally contriv$ ?an ,backmann's helicoidal sy/em4 ,ed\x1 an old s*oolmate ( ,eiffel's1 _h built ?\s&s ( elevators 9 ,france & 0 possibly ! c\ntry's mo/ successful inv5tor & manufactur] 9 ! field4 ,x is likely t he did n attempt to obta9 ! contract = ! elevator equipm5t 9 ! ,t[] legs1 z 8 exp]i5ce 0 bas$ almo/ entirely on plung] sy/ems1 a type1 z we h se51 n readily adaptable to t situation4 ,:at is puzzl+ 0 ! failure ( ! ,commission's memb]s to recognize soon] ,ed\x's obvi\s ability to provide equipm5t = ! upp] run4 ,x may h be5 due to _! inexplicable confid5ce 9 ,backmann4 ,illu/ration3 ,figure #ca4--,! ,fr5* ,gir>d pumps t suppli$ ! ,otis & ,r\x sy/ems4 7,f ,la ,nature1 ,oct4 #e1 #ahhi1 vol4 #ag1 p4 #bib47 ,! direct plung] elevator 0 ! only type 9 :i* ,european practice 0 9 advance ( ,am]ican practice at ?is "t4 ,n until ! beg9n+ ( ! #bj? c5tury1 :5 hydraulic sy/ems 7 =c$ into competition ) electrical sy/ems1 0 ! direct plung] elevator improv$ 9 ,am]ica to ! ext5t ( be+ practically capable ( high rises & spe$s4 ,ano!r reason = its e>ly disfavor 9 ! ,unit$ ,/ates 0 ! necessity = drill+ an exp5sive plung] well equal 9 l5g? to ! rise4#ad ,z m5tion$1 ! mo/ s]i\s problem confront+ ,ed\x 0 ! extremely high rise ( #ebe feet4 ,! ,trocad]o elevator1 !n ! highe/ plung] ma*9e 9 ! _w1 travel$ only ab\t #bcj feet4 ,a second>y difficulty 0 ! e/hetic undesirability ( p]mitt+ a plung] cyl9d] to project d[nw>d a di/ance equal to su* a rise1 :i* w\ld h c>ri$ x directly into ! c5t] ( ! op5 area b5ea? ! fir/ plat=m 7fig4 #f74 ,bo? problems 7 met by an +5i\s modification ( ! basic sy/em4 ,! run 0 divid$ into two equal sections1 ea* ( #bfb feet1 & two c>s 7 us$4 ,"o op]at$ f ! bottom ( ! run at ! second plat=m level to an int]m$iate plat=m half-way up1 :ile ! o!r op]at$ f ?is po9t to ! obs]vation plat=m ne> ! top ( ! ,t[]4 ,! two sections 7 ( c\rse p>allel1 b (fset4 ,a c5tral guide1 on ! ,t[]'s c5t]-l9e1 runn+ ! entire #ebe feet s]v$ bo? c>s1 ) %ort] guides on ei!r side--"o = ! upp] & "o = ! l[] run4 ,?us1 ea* c> travel$ only half ! total di/ance4 ,! two c>s 7 connect$1 z 9 ! ,backmann sy/em1 by /eel cables runn+ ov] %eaves at ! top1 balanc+ ea* o!r & elim9at+ ! ne$ = c\nt]weights4 ,two driv+ rams 7 us$4 ,by be+ plac$ b5ea? ! upp] c>1 _! cyl9d]s ext5d$ d[nw>d only ! #bfb feet to ! second plat=m & s did n project beyond ! conf9es ( ! sy/em itself4#ae ,9 mak+ ! upw>d or d[nw>d trip1 ! pass5g]s _h to *ange f "o c> to ! o!r at ! int]m$iate plat=m1 :]e ! two met & p>t$ 7fig4 #ci74 ,?is transf] 0 ! only undesirable feature ( :at 01 on ! :ole1 a ?or\ghly effici5t & well design$ "w ( elevator eng9e]+4 ,illu/ration3 ,figure #cb4--,! ,otis di/ributor1 ) valves %[n 9 motionless1 neutral position4 ,s9ce ! ma9 valve at all times 0 subject$ to ! full op]at+ pressure1 x 0 necess>y to drive ?is valve ) a s]vo pi/on4 ,! control cable op]at$ only ! s]vo pi/on's valve4 7,adapt$ f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 p4 #acj47 ,illu/ration3 ,figure #cc4--;,g5]al arrangem5t ( ! ,r\x ,combaluzi] & ,lepape elevator4 ,illu/ration3 ,figure #cd4--,r\x1 ,combaluzi] & ,lepape ma*9]y & cab9 at ! ,t[]'s base4 7,f ,la ,nature1 ,aug4 #aj1 #ahhi1 vol4 #ag1 p4 #afh47 ,9 op]ation1 wat] 0 admitt$ to ! two cyl9d]s f a tank on ! ?ird plat=m4 ,! resultant hydraulic head 0 suffici5t to =ce out ! rams & raise ! upp] c>4 ,z ! rams & c> rose1 ! ris+ wat] level 9 ! cyl9d]s caus$ a progressive r$uction ( ! available head4 ,?is negative effect 0 fur!r height5$ by ! fact t1 z ! rams mov$ upw>d1 less & less ( _! l5g? 0 buoy$ by ! wat] )9 ! cyl9d]s1 increas+ _! effective weight4 ,^! two factors 71 h[ev]1 exactly comp5sat$ = by ! l5g!n+ ( ! cables on ! o!r side ( ! pulleys z ! l[] c> desc5d$4 ,p]fect balance ( ! sy/em's dead load = any position ( ! cab9s 01 !re=e1 a quality inh]5t 9 its design4 ,h[ev]1 !re 7 two extreme conditions ( live load+ :i* requir$ consid]ation3 ! l[] c> full & ! upp] empty1 or vice v]sa4 ,to p]mit ! upp] c> to desc5d "u ! fir/ condition1 ! plung]s 7 made suffici5tly heavy1 by ! addition ( ca/ iron at _! l[] ends1 to ov]balance ! weight ( a capacity load 9 ! l[] c>4 ,! second condition dem&$ simply t ! sy/em be p[]ful en\gh to lift ! unbalanc$ weight ( ! plung]s plus ! weight ( pass5g]s 9 ! upp] c>4 ,z 9 ! o!r sy/ems1 safety 0 a matt] ( prime importance4 ,9 ?is case1 ! elem5t ( risk lay 9 ! possibility ( ! susp5d$ c> fall+4 ,! upp] c>1 re/+ on ! rams1 0 virtually free ( su* dang]4 ,"h aga9 ! influ5ce ( ,backmann 0 felt--a brake ( 8 design 0 appli$ 7fig4 #ch74 ,x 01 true to =m1 a ?r[back1 simil> safety devices hav+ prov5 unsuccessful mu* e>li]4 ,atta*$ to ! l[] c> 7 two helically ?read$ v]tical roll]s1 work+ )9 ! holl[ guides4 ,correspond+ helical ribs 9 ! guides rotat$ ! roll]s z ! c> mov$4 ,if ! c> spe$ exce$$ a set limit1 ! increas$ resi/ance (f]$ by ! app>atus drove ! roll]s up into friction cups1 sl[+ or /opp+ ! c>4 ,illu/ration3 ,figure #ce4--;,detail ( l9ks 9 ! ,r\x sy/em4 7,f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 p4 #aef47 ,illu/ration3 ,figure #cf4--,section ( guide trunks 9 ! ,r\x sy/em4 7,f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 p4 #aef47 ,! device 0 consid]$ ineffectual by ,ed\x & ,eiffel1 :o 7 aw>e t ! ultimate safety ( ! sy/em result$ f ! use ( support+ cables f> heavi] ?an necess>y4 ,!re 7 f\r su* cables1 ) a total sectional area ( #ae4e squ>e in*es4 ,! total maximum load to :i* ! cables might be subject$ 0 ab\t #dg1jjj p\nds1 produc+ a /ress ( ab\t #c1jjj p\nds p] squ>e in* comp>$ to a break+ /ress ( #adj1jjj p\nds p] squ>e in*--a safety factor ( #df6af ,illu/ration3 ,figure #cg4--,s*ematic diagram ( ! ,ed\x sy/em4 7,adapt$ f ,gu/ave ,eiffel1 ,la ,t\r de ,trois ,c5ts ,mtres1 ,p>is1 #aijj1 p4 #age47 ,illu/ration3 ,figure #ch4--,v]tical section ?r\gh l[] 7susp5d$7 ,ed\x c>1 %[+ ,backmann helicoidal safety brake4 7,adapt$ f ,gu/ave ,eiffel1 ,la ,t\r ,eiffel en #aijj1 ,p>is1 #aijb1 p4 #ab47 ,a curiosity 9 connection ) ! ,ed\x sy/em 0 ! use ( ,wor?+ton 7,am]ican7 pumps 7fig4 #dj7 to c>ry ! wat] exhau/$ f ! cyl9d]s back to ! supply tanks4 ,no record has be5 f\nd t might expla9 :y ?is p>ticul> exception 0 made to ! =eign mat]ials /ipulation4 ,?is exception is ev5 m /range 9 view ( ,otis' futile reque/ = ! same pumps & ! fact t any numb] ( native ma*9es mu/ h be5 available4 ,x is possible t ,ed\x's p]sonal influ5ce 0 suffici5t to ov]come ! au?ority ( ! regulation4 ,illu/ration3 ,figure #ci4--,pass5g]s *ang+ c>s on ,ed\x elevator at int]m$iate plat=m4 7,f ,la ,nature1 ,may #d1 #ahhi1 vol4 #ag1 p4 #cfa47 ,illu/ration3 ,figure #dj4--,wor?+ton t&em comp\nd /eam pumps1 at base ( ! ,t[]'s s\? pi]1 suppli$ wat] = ! ,ed\x sy/em4 ,! tank 0 at #hif feet1 b suction 0 tak5 f ! top ( ! cyl9d]s at #fdc feet2 !re=e1 ! pumps work$ aga9/ a head ( only ab\t #bej feet4 7,f ,la ,nature1 ,oct4 #e1 #ahhi1 vol4 #ag1 p4 #bic47 ,illu/ration3 ,figure #da4--,rec5t view ( l[] c> ( ! ,ed\x sy/em1 %[+ slott$ cyl9drical guides t enclose ! cables4 ,epilogue ,9 #aijj1 aft] ! cu/om>y #aa-ye> p]iod1 ,p>is aga9 prep>$ = an int]national exposition1 ab\t #e ye>s too e>ly to take advantage ( ! great progress made by ! electric elevator4 ,:5 ! ,r\x ma*9es1 ! weake/ elem5t 9 ! ,eiffel ,t[] sy/em1 7 replac$ at ?is "t1 x 0 by o!r hydraulics4 ,built by ! well kn[n ,fr5* eng9e]+ organization ( ,fives-,lilles1 ! new ma*9es 7 ! ultimate 9 p[]1 control1 & g5]al excell5ce ( op]ation4 ,z 9 ! ,otis sy/em1 ! c>s ran all ! way to ! second plat=m4 ,! ,fives-,lilles equipm5t reflect$ ! advance ( ,european elevator eng9e]+ 9 ?is %ort "t4 ,! ma*9es 7 rope-ge>$ & incorporat$ ! elegant feature ( self-level+ cab9s :i* comp5sat$ = ! v>y+ track incl9ation4 ,= ! #aijj fair1 ! ,otis elevator 9 ! s\? pi] 0 also remov$ & a wide /airway to ! fir/ plat=m built 9 its place4 ,9 #aiab1 #be ye>s aft] ,backmann's />tl+ proposal to use electricity = 8 sy/em1 ! rema9+ ,otis elevator 0 replac$ by a small electric "o4 ,?is innovation 0 reluctantly introduc$ solely = ! purpose ( accommodat+ visitors 9 ! w9t] :5 ! hydraulic sy/ems 7 %ut d[n due to freez+ wea!r4 ,! electric elevator _h a %ort life1 be+ remov$ 9 #aibb :5 ! numb] ( w9t] visitors increas$ f> beyond its capacity4 ,h[ev]1 ! two hydraulic sy/ems 7 modifi$ to op]ate 9 freez+ temp]atures--presumably by ! simple exp$i5t ( add+ an antifreez+ *emical to ! wat]--& op]ation 0 plac$ on a ye>-r\nd basis4 ,today ! two ,fives-,lilles hydraulic sy/ems rema9 9 full use2 & visitors rea* ! ,t[]'s summit by ,ed\x's elevator 7fig4 #da71 :i* is all t rema9s ( ! orig9al in/allation4 ,,balance ,,( ,,! ,,?ree ,,elevator ,,sy/ems ,! ,otis ,sy/em ,negative effect ,weight ( cab93 #bc1ijj lb4 s9 #ghi' 7incl9e ( upp] run7 #bc1cij lb4 ,live load3 #dj p]sons #aej lb4 #f1jjj s9 #ghi' #e1hgb ------ -- #bi1bfb lb4 ,positive effect ,c\nt]weight3 #ee1jjj s9 #edce' 7incl9e ( l[] run7 ---------------------------------------- -- #c 7rope ge> ratio7 #ad1idj lb4 ,weight ( pi/on & *>iot3 #cc1jfj s9 #edce' ------------------ #ab 7ratio7 #b1bde ,p[]3 #aef p4s4i4 #a1acd sq4 94 7pi/on area7 ---------------------------------------- #ab 7ratio7 #ad1gdb #ca1ibg lb4 ,excess to ov]come friction #b1ffe lb4 ,! ,r\x1 ,combaluzi] & ,lepape ,sy/em ,negative effect ,weight ( cab93 #ad1ajj s9 #edce' #aa1ejj lb4 ,live load3 #ajj p]sons #aej lb4 #ae1jjj s9 #edce' #ab1bbj ------ -- #bc1gbj lb4 ,positive effect ,c\nt]weight3 #f1fjj s9 #edce' #e1chj ,p[]3 #aef p4s4i4 #b 7pi/ons7 #a1cda4e sq4 94 7pi/on area7 ---------------------------------------- -- #ac 7ratio7 #cb1aif #cg1egf lb4 ------ ---------- ,excess to ov]come friction #ac1hef lb4 ,! ,ed\x ,sy/em ,negative effect ,unbalanc$ weight ( plung]s 7necess>y to raise full l[] c> & weight ( cables on l[] side7 #db1ccj lb4 ,live load3 #fj p]sons #aej lb4 #i1jjj ------ -- #ea1ccj lb4 ,positive effect ,p[]3 #bbg4e p4s4i4 #b 7plung]s7 #abd sq4 94 7plung] area7 #ef1dbj lb4 ---------- ,excess to ov]come friction #e1jij lb4 ,footnotes3 #a ,translat$ f ,jean ,a4 ,keim1 ,la ,t\r ,eiffel1 ,p>is1 #aiej4 #b ,! f\ndation foot+s ex]t$ a pressure on ! e>? ( ab\t #bjj p\nds p] squ>e foot1 r\ghly "o-six? t ( ! ,wa%+ton ,monum5t1 !n ! highe/ /ructure 9 ! _w4 #c ,a type ( elevator kn[n z ! teagle 0 9 use 9 "s multi/ory ,engli% factories by ab\t #ahce4 ,f its description1 ?is elevator appe>s to h be5 prim>ily = ! use ( pass5g]s1 b x unque/ionably c>ri$ freight z well4 ,! ma*9e %[n 9 figure #g _h1 ) ! exception ( a c> safety1 all ! features ( lat] sy/ems driv5 f l9e %aft+--c\nt]weight1 control f ! c>1 & rev]sal by /raight & cross$ belts4 #d ,! ,otis safety1 ( :i* a modifi$ =m is /ill us$1 consi/$ ess5tially ( a leaf wagon spr+1 on ! c> frame1 kept /ra9$ by ! t5sion ( ! hoi/+ cables4 ,if ^! gave way1 ! spr+1 releas$1 drove dogs into cont9u\s racks on ! v]tical guides1 hold+ ! c> or plat=m 9 place4 #e ,a notable exception 0 ! elevator 9 ! ,wa%+ton ,monum5t4 ,in/all$ 9 #ahhj = rais+ mat]ials dur+ ! /ructure's f9al p]iod ( erection & aft]w>ds conv]t$ to pass5g] s]vice1 x 0 = _m ye>s ! highe/-rise elevator 9 ! _w 7ab\t #ejj feet71 & 0 c]ta9ly among ! sl[e/1 hav+ a spe$ ( #ej feet p] m9ute4 #f ,today1 al?\gh n limit$ by ! ma*9]y1 spe$s are set at a maximum ( ab\t #a1djj feet p] m9ute4 ,if high] spe$s 7 us$1 an impractically long express run w\ld be necess>y = />t+ & /opp+ 9 ord] to prev5t an accel]ation s rapid z to be uncom=table to pass5g]s & a /ra9 on ! equipm5t4 #g ,two ma*9es1 by ,otis1 9 ! ,dem>e/ ,build+1 ,fif? ,av5ue & #cc;d ,/reet1 ,new ,york4 ,!y 7 9 use = ov] #cj ye>s4 #h ,al?\gh ! ev5tually successful application ( electric p[] to ! elevator did n occur until #aijd1 & !re=e goes beyond ! *ronological scope ( ?is discussion1 x 0 ( su* importance ins(> z curr5t practice is conc]n$ z to be wor?y ( brief m5tion4 ,9 t ye> ! fir/ ge>less traction ma*9e 0 in/all$ by ,otis 9 a ,*icago !atre4 ,z ! "n implies1 ! cables 7 n wrapp$ on a drum b pass$1 f ! c>1 ov] a groov$ %eave directly on ! motor %aft1 ! o!r ends be+ atta*$ to ! c\nt]weights4 ,! result 0 a sy/em ( beautiful simplicity1 capable ( any rise & spe$ ) no proportionate increase 9 ! numb] or size ( its p>ts1 & free f any possibility ( c> or weights be+ drawn into ! ma*9]y4 ,?is sy/em is /ill ! only "o us$ = rises ( ov] #ajj feet or s4 ,by ! "t ( its introduction1 motor controls _h be5 improv$ to ! po9t ( complete practicability4 #i ,me*anical transmission ( p[] by wire rope 0 a well develop$ practice at ?is "t1 involv+ 9 _m in/ances high p[]s & di/ances up to a mile4 ,to attempt ?is sy/em 9 ! ,eiffel ,t[]1 cr[d$ ) /ructural "w1 ma*9]y & p1 0 ano!r matt]4 #aj ,accord+ to ,otis ,elevator ,company1 ! f9al price1 because ( extras1 0 #cj1jjj4 #aa ,9 ,pall ,mall ,gazette1 z quot$ 9 ,! ,eng9e]+ & ,build+ ,record & ! ,sanit>y ,eng9e]1 ,may #be1 #ahhi1 vol4 #ai1 p4 #cde4 #ab ,f spee* at annual summ] meet+ ( ,in/itution ( ,me*anical ,eng9e]s1 ,p>is1 #ahhi4 ,quot$ 9 ,eng9e]+1 ,july #e1 #ahhi1 vol4 #dh1 p4 #ah4 #ac ,locat$ ne> ! ,t[]1 built = ! ,p>is fair ( #ahgh4 #ad ,improv$ oil-well drill+ te*niques 7 influ5tial 9 ! int5se b %ort bur/ ( popul>ity enjoy$ by direct plung] sy/ems 9 ! ,unit$ ,/ates betwe5 #ahii & #aiaj4 ,9 ,new ,york1 _m su* sy/ems ( #bjj-;foot rise1 & "o ( #chj feet1 7 in/all$4 #ae ,an obvi\s "q arises "h3 ,:at prev5ts a plung] #bjj or #cjj feet long & no m ?an #af in*es 9 diamet] f buckl+ "u its compressive load+8 ,! answ] is simply t mo/ ( ?is l5g? is n 9 compression b 9 t5sion4 ,! ,ed\x rams1 :5 fully ext5d$1 virtually hung f ! upp] c>1 su/a9$ by ! weight ( #ejj feet ( cable on ! o!r side ( ! %eaves4 ,z ! upp] c> desc5d$ ?is effect dim9i%$1 b z ! rams mov$ back into ! cyl9d]s _! unsupport$ l5g? 0 correspond+ly r$uc$4 #af ,m4 ,a4 ,ansaloni1 ,! ,lifts 9 ! ,eiffel ,t[]1 quot$ 9 ,eng9e]+1 ,july #e1 #ahhi1 vol4 #dh1 p4 #bc4 ,! /r5g? ( /eel :5 drawn into wire is increas$ trem5d\sly4 ,break+ /resses ( #adj1jjj p4s4i4 7 n p>ticul>ly high at ! "t4 ,special cables ) break+ /resses ( up to #cgj1jjj p4s4i4 7 available4 ,transcrib]'s ,notes3 ,passages 9 italics are indicat$ by und]score4 ,! orig9al 0 pr9t$ 9 two columns p] page4 ,illu/rations h be5 mov$ to ! ne>e/ p>agraph break4 ,! foll[+ mispr9ts h be5 correct$3 ,treve?ick's correct$ to ,trevi?ick's 7page #e7 !n correct$ to ?an 7page #ad7 smili> correct$ to simil> 7page #ca7