,book provid$ by ! ,new ,york ,univ]sity ,libr>y4 includes ! orig9al m ?an #ahj illu/rations4 ,see #agjba-;h4htm or #agjba-;h4zip3 7https3_/_/www4gut5b]g4org_/dirs_/#a_/g_ /j_/b_/agjba_/agjba-;h_/#agjba-;h4htm7 or 7https3_/_/www4gut5b]g4org_/dirs_/#a_/g_ /j_/b_/agjba_/agjba-;h4zip7 ,,wat* ,,& ,,clock ,,escapem5ts ,a ,complete ,/udy 9 ,!ory & ,practice ( ! ,lev]1 ,cyl9d] & ,*ronomet] ,escapem5ts1 ,toge!r ) a ,brief ,acc\nt ( ! ,orig9 & ,evolution ( ! ,escapem5t 9 ,horology ,compil$ f ! well-kn[n ,escapem5t ,s]ials publi%$ 9 ,! ,key/one ,ne>ly ,two ,hundr$ ,orig9al ,illu/rations ,publi%$ by ,! ,key/one ,! ,organ ( ! ,jewelry & ,optical ,trades #ai? ,br[n ,/s41 ,philadelphia1 ,u4,s4,a4 #aijd ,all ,rights ,res]v$ ,copyright1 #aijd1 ,by ,b4 ,?orpe1 ,publi%] ( ! ,key/one4 ,,preface ,especially notable among ! a*ievem5ts ( ,! ,key/one 9 ! field ( horology 7 ! ?ree s]ials devot$ to ! lev]1 cyl9d] & *ronomet] escapem5ts4 ,s highly valu$ 7 ^! s]ials :5 publi%$ t on ! completion ( ea* we 7 importun$ to republi% x 9 book =m1 b we deem$ x advisable to po/pone su* publication until ! completion ( all ?ree1 9 ord] t ! volume %\ld be a complete treatise on ! sev]al escapem5ts 9 use 9 horology4 ,! rec5t completion ( ! ?ird s]ial gave u ! opportunity to republi% 9 book =m1 & ! pres5t volume is ! result4 ,we pres5t x to ! trade & /ud5ts ( horology happy 9 ! k t its cont5ts h already receiv$ _! approval4 ,an int]e/+ addition to ! book is ! illu/rat$ /ory ( ! escapem5ts1 f ! fir/ crude conceptions to _! pres5t p]fection4 ,,cont5ts ,,*apt] ,i4 ,,! ,,deta*$ ,,lev] ,,escapem5t #i ,,*apt] ,,ii4 ,,! ,,cyl9d] ,,escapem5t #aaa ,,*apt] ,,iii4 ,,! ,,*ronomet] ,,escapem5t #aca ,,*apt] ,,iv4 ,,hi/ory ,,( ,,escapem5ts #aec ,,*apt] ,v4 ,,putt+ ,,9 ,a ,,new ,,cyl9d] #afi ,,index #agg ,,wat* ,,& ,,clock ,,escapem5ts ,,*apt] ,i4 ,,! ,,deta*$ ,,lev] ,,escapem5t4 ,9 ?is treatise we d n propose to g into ! hi/ory ( ?is escapem5t & give a long diss]tation on its orig9 & evolution1 b %all conf9e ourselves /rictly to ! design+ & con/ruction z employ$ 9 our be/ wat*es4 ,by design+1 we mean giv+ full in/ructions = draw+ an escapem5t ( ?is k9d to ! be/ proportions4 ,! workman w ne$ b few draw+ in/rum5ts1 & a draw+-bo>d ab\t #ae by #ah w be q l>ge en\gh4 ,! necess>y draw+-in/rum5ts are a ,t-squ>e ) #ae blade2 a scale ( in*es divid$ into decimal p>ts2 two pairs divid]s ) p5 & p5cil po9ts--"o pair ( ^! divid]s to be #e & ! o!r #f2 "o rul+ p54 ,o!r in/rum5ts c be add$ z ! workman f9ds he ne$s !m4 ,^? enum]at$ above1 h[ev]1 w be all t are absolutely necess>y4 ,illu/ration3 ,fig4 #a ,we %all1 9 addition1 ne$ an arc ( degrees1 :i* we c be/ make = ourselves4 ,to con/ruct "o1 we procure a piece ( ,no4 #bd brass1 ab\t #e long by #a wide4 ,we %[ su* a piece ( brass at ,a1 ,fig4 #a4 ,on ?is piece ( brass we sweep two arcs ) a pair ( divid]s set at precisely #e1 z %[n 7r$uc$7 at a a & b b4 ,on ^! arcs we set (f ! space held 9 our divid]s--t is #e--;z %[n at ! %ort radial l9es at ea* end ( ! two arcs4 ,n[ x is a well-kn[n fact t ! space embrac$ by our divid]s conta9s exactly sixty degrees ( ! arcs a a & b b1 or "o-six? ( ! entire circle2 consequ5tly1 we divide ! arcs a a & b b into sixty equal p>ts1 to repres5t degrees1 & at "o end ( ^! arcs we halve five spaces s we c get at half degrees4 ,illu/ration3 ,fig4 #b ,be=e we take up ! details ( draw+ an escapem5t we w say a few words ab\t degrees1 z ?is seems to be some?+ difficult to und]/& by mo/ pupils 9 horology :5 le>n+ to draw p>ts ( wat*es to scale4 ,at ,fig4 #b we %[ sev]al %ort arcs ( fifte5 degrees1 all hav+ ! common c5t] g4 ,mo/ le>n]s seem to h an idea t a degree mu/ be a specific space1 l an in* or a foot4 ,n[ ! fir/ ?+ 9 le>n+ to draw an escapem5t is to fix 9 our m9ds ! fact t ! ext5t ( a degree dep5ds entirely on ! radius ( ! arc we employ4 ,to aid 9 ?is explanation we ref] to ,fig4 #b4 ,"h ! arcs c1 d1 e & f are all fifte5 degrees1 al?\gh ! l9e> ext5t ( ! degree on ! arc c is twice t ( ! degree on ! arc f4 ,:5 we speak ( a degree 9 connection ) a circle we mean ! "o-?ree-hundr$-&-sixtie? "p ( ! p]iph]y ( su* a circle4 ,9 divid+ ! arcs a a & b b we fir/ divide !m into six spaces1 z %[n1 & ea* ( ^! spaces into t5 m9or spaces1 z is also %[n4 ,we halve five ( ! degree spaces1 z %[n at h4 ,we %\ld be v c>eful ab\t mak+ ! degree arcs %[n at ,fig4 #a1 z ! accuracy ( our draw+s dep5ds a great deal on ! p]fection ( ! division on ! scale ,a4 ,9 connection ) su* a fix$ scale ( degrees z is %[n at ,fig4 #a1 a pair ( small divid]s1 con/antly set to a degree space1 is v conv5i5t4 ,,mak+ ,a ,,pair ,,( ,,divid]s4 ,illu/ration3 ,fig4 #c ,to make su* a pair ( small divid]s1 take a piece ( h>d %eet brass ab\t #a_/bj ?ick1 wide1 #a long1 & %ape x z %[n at ,fig4 #c4 ,x %\ld be expla9$1 ! "p cut f ! %eet brass is %[n bel[ ! dott$ l9e k1 ! portion above 7,c7 be+ a r\nd h&le turn$ f h>d wood or ivory4 ,! slot l is sawn 91 & two holes drill$ 9 ! end to ins]t ! ne$le po9ts i i4 ,9 mak+ ! slot l we arrange to h ! ne$le po9ts come a little too close toge!r to agree ) ! degree spaces on ! arcs a a & b b4 ,we !n put ! small screw j ?r\gh "o ( ! legs ,d''1 & by turn+ j1 set ! ne$le po9ts i i to exactly agree ) ! degree spaces4 ,z soon z ! po9ts i i are set correctly1 j %\ld be s(t sold]$ fa/4 ,! degree spaces on ,a are set (f ) ^! divid]s & ! spaces on ,a v c>efully m>k$4 ,! upp] & out] arc a a %\ld h ! spaces cut ) a grav] l9e1 :ile ! l[] "o1 b b is be/ p]man5tly m>k$ ) a c>efully-made prick pun*4 ,aft] ! arc a a is divid$1 ! brass plate ,a is cut back to ?is arc s ! divisions we h j made are on ! edge4 ,! object ( hav+ two arcs on ! plate ,a is1 if we desire to get at ! numb] ( degrees conta9$ 9 any arc ( a #e radius we lay ! scale ,a s ! edge agrees ) ! arc a a1 & read (f ! numb] ( degrees f ! scale4 ,9 sett+ divid]s we employ ! dott$ spaces on ! arc b b4 ,,del9eat+ ,,an ,,escape ,,:eel4 ,illu/ration3 ,fig4 #d ,we w n[ proce$ to del9eate an escape :eel = a deta*$ lev]4 ,we place a piece ( good draw+-pap] on our draw+-bo>d & provide ourselves ) a v h>d 7,,hhh7 draw+-p5cil & a bottle ( liquid ,india ink4 ,aft] plac+ our pap] on ! bo>d1 we draw1 ) ! aid ( our ,t-squ>e1 a l9e ?r\gh ! c5t] ( ! pap]1 z %[n at m m1 ,fig4 #d4 ,at #e f ! l[] m>g9 ( ! pap] we e/abli% ! po9t p & sweep ! circle n n ) a radius ( #e4 ,we h said no?+ ab\t /ret*+ our pap] on ! draw+-bo>d2 /ill1 c>efully-/ret*$ pap] is an important "p ( nice & correct draw+4 ,we %all subsequ5tly give directions = prop]ly /ret*+ pap]1 b = ! pres5t we w suppose ! pap] we are us+ is nicely tack$ to ! face ( ! draw+-bo>d ) ! smalle/ tacks we c procure4 ,! pap] %\ld n come q to ! edge ( ! draw+-bo>d1 s z to int]f]e ) ! head ( ! ,t-squ>e4 ,we are n[ ready to comm5ce del9eat+ our escape :eel & a set ( pallets to mat*4 ,! simple/ =m ( ! deta*$ lev] escapem5t 9 use is ! "o kn[n z ! rat*et-too? lev] escapem5t1 & g5]ally f\nd 9 ,engli% lev] wat*es4 ,?is =m ( escapem5t gives excell5t results :5 well made2 & we c only acc\nt = x n be+ 9 m g5]al use f ! fact t ! escape-:eel tee? are n s /rong & capable ( resi/+ c>eless usage z ! club-too? escape :eel4 ,x w be our aim to convey broad ideas & inculcate g5]al pr9ciples1 r ?an to give specific in/ructions = do+ "o ?+ "o way4 ,! rat*et-too? lev] escapem5ts ( lat] dates h almo/ inv>iably be5 con/ruct$ on ! t5-degree lev]-&-pallet-action plan2 t is1 ! =k & pallets 7 int5d$ to act ?r\gh ?is arc4 ,"s ( ! o!r specim5s ( ?is escapem5t h l>g] arcs--"s z high z twelve degrees4 ,,pallet-,,&-,,=k ,,action4 ,illu/ration3 ,fig4 #e ,we illu/rate at ,fig4 #e :at we mean by t5 degrees ( pallet-&-=k action4 ,if we draw a l9e ?r\gh ! c5t] ( ! pallet /aff1 & also ?r\gh ! c5t] ( ! =k slot1 z %[n at a b1 ,fig4 #e1 & all[ ! =k to vibrate five degrees ea* side ( said l9es a b1 to ! l9es a c & a c'1 ! =k has :at we t]m t5-degree pallet action4 ,if ! =k & pallets vibrate six degrees on ea* side ( ! l9e a b--t is1 to ! l9es a d & a d'--we h twelve degrees pallet action4 ,if we cut ! arc d[n s ! oscillation is only f\r & "o-qu>t] degrees on ea* side ( a b1 z indicat$ by ! l9es a s & a s'1 we h a pallet-&-=k action ( eight & "o-half degrees2 :i*1 by ! way1 is a v desirable arc = a c>efully-con/ruct$ escapem5t4 ,! controll+ idea :i* w\ld seem to rule 9 con/ruct+ a deta*$ lev] escapem5t1 w\ld be to make x s ! balance is free ( ! =k2 t is1 deta*$1 dur+ z mu* ( ! arc ( ! vibration ( ! balance z possible1 & yet h ! action ?or\ghly s\nd & secure4 ,:]e a rat*et-too? escapem5t is ?or\ghly well-made ( eight & "o-half degrees ( pallet-&-=k action1 t5 & "o-half degrees ( escape-:eel action c be utiliz$1 z w be expla9$ lat] on4 ,we w n[ resume ! draw+ ( our escape :eel1 z illu/rat$ at ,fig4 #d4 ,9 ! draw+ at ,fig4 #f we %[ ! circle n n1 :i* repres5ts ! p]iph]y ( our escape :eel2 & 9 ! draw+ we are suppos$ to be draw+ x t5 in*es 9 diamet]4 ,we produce ! v]tical l9e m pass+ ?r\gh ! c5t] p ( ! circle n4 ,f ! int]section ( ! circle n ) ! l9e m at i we lay (f ?irty degrees on ea* side1 & e/abli% ! po9ts e f2 & f ! c5t] p1 ?r\gh ^! po9ts1 draw ! radial l9es p e' & p f'4 ,! po9ts f e1 ,fig4 #f1 are1 ( c\rse1 j sixty degrees ap>t & repres5t ! ext5t ( two & "o-half tee? ( ! escape :eel4 ,!re are two sy/ems on :i* pallets = lev] escapem5ts are made1 viz41 equidi/ant lock+s & circul> pallets4 ,! advantages claim$ = ea* sy/em w be discuss$ subsequ5tly4 ,= ! fir/ & pres5t illu/ration we w assume we are to employ circul> pallets & "o ( ! tee? ( ! escape :eel re/+ on ! pallet at ! po9t f2 & ! escape :eel turn+ 9 ! direction ( ! arr[ j4 ,if we imag9e a too? z indicat$ at ! dott$ outl9e at ,d1 ,fig4 #f1 press+ aga9/ a surface :i* co9cides ) ! radial l9e p f1 ! action w\ld be 9 ! direction ( ! l9e f h & at "r angles to p f4 ,if we reason on ! action ( ! too? ,d1 z x presses aga9/ a pallet plac$ at f1 we see ! action is neutral4 ,illu/ration3 ,fig4 #f ,,e/abli%+ ,,! ,,c5t] ,,( ,,pallet ,,/aff4 ,illu/ration3 ,fig4 #g ,) a fifte5-too? escape :eel ea* too? occupies tw5ty-f\r degrees1 & f ! po9t f to e w\ld be two & "o-half too?-spaces4 ,we %[ ! dott$ po9ts ( f\r tee? at ,d ,d' ,d'',d'''4 ,to e/abli% ! c5t] ( ! pallet /aff we draw a l9e at "r angles to ! l9e p e' f ! po9t e s x int]sects ! l9e f h at k4 ,= draw+ a l9e at "r angles to ano!r l9e1 z we h j done1 a h>d-rubb] triangle1 %ap$ z %[n at ,c1 ,fig4 #g1 c be employ$4 ,to use su* a triangle1 we place x s ! "r1 or n9ety-degrees angle1 re/s at e1 z %[n at ! dott$ triangle ,c1 ,fig4 #f1 & ! long side co9cides ) ! radial l9e p e'4 ,if ! %ort side ( ! h>d-rubb] triangle is too %ort1 z indicat$1 we place a %ort rul] s x re/s aga9/ ! edge1 z %[n at ! dott$ l9e g e1 ,fig4 #g1 & :ile hold+ x securely d[n on ! draw+ we remove ! triangle1 & ) a f9e-po9t$ p5cil draw ! l9e e g1 ,fig4 #f1 by ! %ort rule4 ,let u imag9e a flat surface plac$ at e s its face 0 at "r angles to ! l9e g e1 :i* w\ld arre/ ! too? ,d'' aft] ! too? ,d re/+ on f _h be5 releas$ & pass$ ?r\gh an arc ( twelve degrees4 ,a too? re/+ on a flat surface1 z imag9$ above1 w\ld also re/ dead4 ,z /at$ previ\sly1 ! pallets we are consid]+ h equidi/ant lock+ faces & correspond to ! arc l l1 ,fig4 #f4 ,9 ord] to realize any p[] f our escape-:eel too?1 we mu/ provide an impulse face to ! pallets fac$ at f e2 & ! problem be=e u is to del9eate ^! pallets s t ! lev] w be propell$ ?r\gh an arc ( eight & "o-half degrees1 :ile ! escape :eel is mov+ ?r\gh an arc ( t5 & "o-half degrees4 ,we make ! arc ( =k action eight & "o-half degrees = two reasons--7#a7 because mo/ text-books h select$ t5 degrees ( =k-&-pallet action2 7#b7 because mo/ ( ! f9] lev] escapem5ts ( rec5t con/ruction h a lev] action ( less ?an t5 degrees4 ,,lay+ ,,out ,,escape-,,:eel ,,tee?4 ,to lay out or del9eate our escape-:eel tee?1 we cont9ue our draw+ %[n at ,fig4 #f1 & reproduce ?is cut v ne>ly at ,fig4 #h4 ,) our divid]s set at five in*es1 we sweep ! %ort arc a a' f f z a c5t]4 ,x is to be borne 9 m9d t at ! po9t f is locat$ ! extreme po9t ( an escape-:eel too?4 ,on ! arc a a we lay (f f p tw5ty-f\r degrees1 & e/abli% ! po9t b2 at twelve degrees beyond b we e/abli% ! po9t c4 ,f f we draw ! l9es f b & f c2 ^! l9es e/abli%+ ! =m & ?ickness ( ! too? ,d4 ,to get ! l5g? ( ! too?1 we take 9 our divid]s "o-half a too? space1 & on ! radial l9e p f e/abli% ! po9t d & draw circle d' d'4 ,to facilitate ! draw+ ( ! o!r tee?1 we draw ! circles d' c'1 to :i* ! l9es f b & f c are tang5t1 z %[n4 ,we divide ! circle n n1 repres5t+ ! p]iph]y ( our escape :eel1 into fifte5 spaces1 to repres5t tee?1 comm5c+ at f & cont9u$ z %[n at o o until ! entire :eel is divid$4 ,we only %[ f\r tee? complete1 b ! same me?ods z produc$ ^! w produce !m all4 ,to briefly recapitulate ! in/ructions = draw+ ! tee? = ! rat*et-too? lev] escapem5t3 ,we draw ! face ( ! tee? at an angle ( tw5ty-f\r degrees to a radial l9e2 ! back ( ! too? at an angle ( ?irty-six degrees to ! same radial l9e2 & make tee? half a too?-space deep or long4 ,illu/ration3 ,fig4 #h ,we n[ come to ! consid]ation ( ! pallets & h[ to del9eate !m4 ,to ?is we %all add a c>eful analysis ( _! action4 ,let u1 be=e proce$+ fur!r1 ?9k a little ov] "s ( ! factors involv$4 ,to aid 9 ?is ?9k+ or reason+ on ! matt]1 let u draw ! heavy arc l ext5d+ f a little inside ( ! circle n at f to ! circle n at e4 ,if n[ we imag9e our escape :eel to be press$ =w>d 9 ! direction ( ! arr[ j1 ! too? ,d w\ld press on ! arc l & be held4 ,if1 h[ev]1 we %\ld revolve ! arc l on ! c5t] k 9 ! direction ( ! arr[ i1 ! too? ,d w\ld escape f ! edge ( l & ! too? ,d'' w\ld pass ?r\gh an arc 7reckon+ f ! c5t] p7 ( twelve degrees1 & be arre/$ by ! inside ( ! arc l at e4 ,if we n[ %\ld rev]se ! motion & turn ! arc l backw>d1 ! too? at e w\ld1 9 turn1 be releas$ & ! too? foll[+ aft] ,d 7b n %[n7 w\ld engage l at f4 ,by supply+ motive to revolve ! escape :eel 7,e7 repres5t$ by ! circle n1 & caus+ ! arc l to oscillate back & =? 9 exact int]vals ( "t1 we %\ld h1 9 effect1 a p]fect escapem5t4 ,to accompli% automatically su* oscillations is ! problem we h n[ on h&4 ,,h[ ,,motion ,,is ,,obta9$4 ,9 clocks1 ! back-&-=? movem5t1 or oscillat+ motion1 is obta9$ by employ+ a p5dulum2 9 a movable timepiece we make use ( an equally-pois$ :eel ( "s weight on a pivot$ axle1 :i* device we t]m a balance2 ! vibrations or oscillations be+ obta9$ by apply+ a coil$ spr+1 :i* 0 fir/ call$ a p5dulum spr+1 !n a balance spr+1 & f9ally1 f its dim9utive size & coil =m1 a hairspr+4 ,we are all aw>e t = ! motive p[] = keep+ up ! oscillations ( ! escap+ circle l we mu/ contrive to employ p[] d]iv$ f ! tee? ,d ( ! escape :eel4 ,ab\t ! mo/ available means ( convey+ p[] f ! escape :eel to ! oscillat+ arc l is to provide ! lip ( said arc ) an incl9$ plane1 along :i* ! too? :i* is dis5gag$ f l at f to slide & move said arc l ?r\gh--9 ! pres5t in/ance an arc ( eight & "o-half degrees1 dur+ ! "t ! too? ,d is pass+ ?r\gh t5 & "o-half degrees4 ,?is angul> motion ( ! arc l is repres5t$ by ! radial l9es k f' & k r1 ,fig4 #h4 ,we desire to impress on ! read]'s m9d ! idea t ea* ( ^! angul> motions is n only requir$ to be made1 b ! motion ( "o mobile mu/ convey p[] to ano!r mobile4 ,9 ?is case ! p[] convey$ f ! ma9spr+ to ! escape :eel is to be convey$ to ! lev]1 & by ! lev] transmitt$ to ! balance4 ,we "k x is ! usual plan adopt$ by text-books to lay d[n a c]ta9 =mula = draw+ an escapem5t1 leav+ ! pupil to "w & reason out ! pr9ciples involv$ 9 ! action4 ,9 ! plan we h adopt$ we propose to induct ! read] into ! :y & h[1 & po9t out to him ! rules & me?ods ( analysis ( ! problem1 s t he c1 if requir$1 calculate ma!matically exactly h[ _m gra9s ( =ce ! =k ex]ts on ! jewel p91 & also h[ mu* 7or1 r1 :at p]c5tage7 ( ! motive p[] is lo/ 9 v>i\s p[] leaks1 l drop & lo/ motion4 ,9 ! pres5t case ! me*anical result we desire to obta9 is to cause our lev] pivot$ at k to vibrate back & =? ?r\gh an arc ( eight & "o-half degrees2 ?is lev] n only to vibrate back & =?1 b also to lock & hold ! escape :eel dur+ a c]ta9 p]iod ( "t2 t is1 ?r\gh ! p]iod ( "t ! balance is p]=m+ its excursion & ! jewel p9 free & deta*$ f ! =k4 ,we h spok5 ( pap] be+ employ$ = draw+s1 b = v accurate del9eations we w\ld recomm5d ! horological /ud5t to make draw+s on a flat metal plate1 aft] p]fectly smoo?+ ! surface & black5+ x by oxidiz+4 ,,pallet-,,&-,,=k ,,action4 ,by adopt+ eight & "o-half degrees pallet-&-=k action we c utilize t5 & "o-half degrees ( escape-:eel action4 ,we %[ at ,a ,a'1 ,fig4 #i1 two tee? ( a rat*et-too? escape :eel r$uc$ "o-half2 t is1 ! orig9al draw+ 0 made = an escape :eel t5 in*es 9 diamet]4 ,we %all make a radical dep>ture f ! usual practice 9 mak+ cuts on an enl>g$ scale1 = only su* p>ts z we are talk+ ab\t4 ,to expla91 we %[ at ,fig4 #aj ab\t "o-half ( an escape :eel "o eigh? ! size ( our l>ge draw+2 & :5 we wi% to %[ "s portion ( su* draw+ on a l>g] scale we w designate su* enl>gem5t by say+ "o-f\r?1 "o-half or full size4 ,illu/ration3 ,fig4 #i ,at ,fig4 #i we %[ at half size t portion ( our escapem5t embrac$ by ! dott$ l9es d1 ,fig4 #aj4 ,?is plan enables u to %[ v m9utely su* p>ts z we h "u consid]ation1 & yet occupy b little space4 ,! arc a1 ,fig4 #i1 repres5ts ! p]iph]y ( ! escape :eel4 ,on ?is l9e1 t5 & "o-half degrees f ! po9t ( ! too? ,a1 we e/abli% ! po9t c & draw ! radial l9e c c'4 ,x is to be borne 9 m9d t ! arc embrac$ betwe5 ! po9ts b & c repres5ts ! duration ( contact betwe5 ! too? ,a & ! entrance pallet ( ! lev]4 ,! space or %ort arc c n repres5ts ! drop ( ! too?4 ,?is arc ( "o & "o-half degrees ( escape-:eel movem5t is a complete loss ( six & "o-f\r? p] c5t4 ( ! entire p[] ( ! ma9spr+1 z br\ght d[n to ! escapem5t2 /ill1 up to ! pres5t "t1 no rem$y has be5 devis$ to ov]come x4 ,all ! o!r escapem5ts1 includ+ ! *ronomet]1 duplex & cyl9d]1 are q z wa/eful ( p[]1 if n m s4 ,x is usual to con/ruct rat*et-too? pallets s z to utilize b t5 degrees ( escape-:eel action2 b we %all %[ t half a degree m c be utiliz$ by adopt+ ! eight & "o-half degree =k action & employ+ a d\ble-roll] safety action to prev5t ov]-bank+4 ,illu/ration3 ,fig4 #aj ,f ! po9t e1 :i* repres5ts ! c5t] ( ! pallet /aff1 we draw ?r\gh b ! l9e e f4 ,at "o degree bel[ e f we draw ! l9e e g1 & sev5 & "o-half degrees bel[ ! l9e e g we draw ! l9e e h4 ,= del9eat+ ! l9es e g1 etc41 correctly1 we employ a degree-arc2 t is1 on ! l>ge draw+ we are mak+ we fir/ draw ! l9e e b f1 ,fig4 #aj1 & !n1 ) our divid]s set at five in*es1 sweep ! %ort arc i1 & on ?is lay (f fir/ "o degree f ! int]section ( f e ) ! arc i1 & ?r\gh ?is po9t draw ! l9e e g4 ,f ! int]section ( ! l9e f e ) ! arc i we lay (f eight & "o-half degrees1 & ?r\gh ?is po9t draw ! l9e e h4 ,be> 9 m9d t we are draw+ ! pallet at ,b to repres5t "o ) eight & "o-half degrees =k-&-pallet action1 & ) equidi/ant lock+s4 ,if we reason on ! matt] "u consid]ation1 we w see ! too? ,a & ! pallet ,b1 aga9/ :i* x acts1 "p or sep>ate :5 ! too? arrives at ! po9t c2 t is1 aft] ! escape :eel has mov$ ?r\gh t5 & "o-half degrees ( angul> motion1 ! too? drops f ! impulse face ( ! pallet & falls ?r\gh "o & "o-half degrees ( arc1 :5 ! too? ,a''1 ,fig4 #aj1 is arre/$ by ! exit pallet4 ,to locate ! position ( ! inn] angle ( ! pallet ,b1 sweep ! %ort arc l by sett+ ! divid]s s "o po9t or leg re/s at ! c5t] e & ! o!r at ! po9t c4 ,some:]e on ?is arc l is to be locat$ ! inn] angle ( our pallet4 ,9 del9eat+ ?is angle1 ,moritz ,grossman1 9 8 ,prize ,essay on ! ,deta*$ ,lev] ,escapem5t1 makes an error1 9 ,plate ,,iii ( l>ge ,engli% edition1 ( m ?an 8 entire lock1 or ab\t two degrees4 ,we make no apologies = call+ att5tion to ?is mi/ake on ! "p ( an au?ority hold+ s high a position on su* matt]s z ,mr4 ,grossman1 because a mi/ake is a mi/ake1 no matt] :o makes x4 ,we w say no m ( ?is error at pres5t1 b w f>!r on %[ draw+s ( ,mr4 ,grossman's faulty me?od1 & also ! correct me?od ( draw+ su* a pallet4 ,to del9eate ! lock+ face ( our pallet1 f ! po9t =m$ by ! int]section ( ! l9es e g b b'1 ,fig4 #i1 z a c5t]1 we draw ! l9e j at an angle ( twelve degrees to b b''4 ,9 do+ ?is we employ ! same me?od ( e/abli%+ ! angle z we made use ( 9 draw+ ! l9es e g & e h1 ,fig4 #aj4 ,! l9e j e/abli%es ! lock+ face ( ! pallet ,b4 ,sett+ ! lock+ face ( ! pallet at twelve degrees has be5 f\nd 9 practice to give a safe draw to ! pallet & keep ! lev] secure aga9/ ! bank4 ,x w be rememb]$ ! face ( ! escape-:eel too? 0 drawn at tw5ty-f\r degrees to a radial l9e ( ! escape :eel1 :i*1 9 ?is in/ance1 is ! l9e b b'1 ,fig4 #i4 ,x w n[ be se5 t ! angle ( ! pallet j halves ?is angle1 & consequ5tly ! too? ,a only re/s ) its po9t on ! lock+ face ( ! pallet4 ,we d n %[ ! outl9es ( ! pallet ,b1 because we h n s f> po9t$ out ! correct me?od ( del9eat+ x4 ,,me?ods ,,( ,,mak+ ,,good ,,draw+ ,,in/rum5ts4 ,p]haps we _c d our read]s a great] favor ?an to digress f ! /udy ( ! deta*$ lev] escapem5t long en\gh to say a few words ab\t draw+ in/rum5ts & tablets or surfaces on :i* to del9eate1 ) due precision1 me*anical designs or draw+s4 ,ord9>y draw+ in/rum5ts1 ev5 ( ! high] grades1 & co/+ a good deal ( money1 are f> f be+ satisfactory to a man :o has ! prop] idea ( accuracy to be rat$ z a fir/-class me*anic4 ,ord9>y compasses are ob/9ate :5 we try to set !m to ! hundr$? ( an in*2 usually ! po9ts are dull & ill-%ap52 if !y make a puncture 9 ! pap] x is unsightly4 ,wat*mak]s h "o advantage1 h[ev]1 because !y c v easily "w ov] a *eap set ( draw+ in/rum5ts & make !m ev5 sup]ior to any?+ !y c buy at ! art /ores4 ,to illu/rate1 let u take a *eap pair ( brass or ,g]man-silv] five-in* divid]s & make !m ov] into ne$le po9ts & spr+ set4 ,to d ?is ! po9ts are cut (f at ! l9e a a1 ,fig #aa1 & a /eel tube is gold-sold]$ on ea* leg4 ,! /eel tube is made by tak+ a piece ( /eel wire :i* w fit a ,no4 #af *uck ( a ,:itcomb la!1 & drill+ a hole 9 ! end ab\t "o-f\r? ( an in* deep & ab\t ! size ( a ,no4 #c sew+ ne$le4 ,we ,%[ at ,fig4 #ab a view ( ! po9t ,a'1 ,fig4 #aa1 enl>g$1 & ! /eel tube we h j drill$ out atta*$ at ,c4 ,ab\t ! be/ way to atta* ,c is to sold]4 ,aft] ! tube ,c is atta*$ a hole is drill$ ?r\gh ,a' at d1 & ! ?umb-screw d ins]t$4 ,?is ?umb-screw %\ld be ( /eel1 & h>d5$ & temp]$4 ,! use ( ?is screw is to clamp ! ne$le po9t4 ,) su* a device z ! tube ,c & set-screw d1 a ,no4 #c ne$le is us$ = a po9t2 b = draw+s on pap] a turn$ po9t1 z %[n at ,fig #ac1 is to be pref]r$4 ,su* po9ts c be made f a ,no4 #c ne$le aft] s(t5+ en\gh to be turn$ s z to =m ! po9t c4 ,?is po9t at ! %\ld] f %\ld be ab\t #ab_/ajjj ( an in*1 or ! size ( a f\r?-:eel pivot to an eighte5 size movem5t4 ,illu/ration3 ,fig4 #aa ,illu/ration3 ,fig4 #ab ,illu/ration3 ,fig4 #ac ,illu/ration3 ,fig4 #ad ,! idea is1 :5 draw+ on pap] ! po9t c ent]s ! pap]4 ,= draw+ on metal ! =m ( ! po9t is *ang$ to a simple cone1 z %[n at ,b' c1 ,fig4 #ac4 su* cones c be turn$ c>efully1 !n h>d5$ & temp]$ to a /raw color2 & :5 !y become dull1 c be gr\nd by plac+ ! po9ts 9 a wire *uck & dress+ !m up ) an em]y buff or an ,arkansas slip4 ,! opposite leg ( ! divid]s is ! "o to :i* is atta*$ ! spr+ = close sett+ ( ! po9ts4 ,9 mak+ ?is spr+1 we take a piece ( /eel ab\t two & "o-f\r? in*es long & ( ! same wid? z ! leg ( ! divid]1 & atta* x to ! inside ( ! leg z %[n at ,fig4 #ad1 :]e ,d repres5ts ! spr+ & ,a ! leg ( ! divid]s4 ,! spr+ ,d has a %ort /eel tube ,c'' & set-screw d'' = a f9e po9t l ,b or ,b'4 ,9 ! l[] end ( ! leg ,a1 ,fig4 #ad1 is plac$ ! mill$-head screw g1 :i* s]ves to adju/ ! two po9ts ( ! divid]s to v close di/ances4 ,! spr+ ,d is1 ( c\rse1 set s x w\ld press close to ! leg ,a if ! screw g did n =ce x away4 ,,spr+ ,,& ,,adju/+ ,,screw ,,= ,,draw+ ,,in/rum5ts4 ,illu/ration3 ,fig4 #ae ,x w be se5 t we c apply a spr+ ,d & adju/+ screw opposite to ! leg :i* c>ries ! p5 or p5cil po9t ( all our divid]s if we *oose to d s2 b x is = metal draw+ t su* po9ts are ( ! greate/ advantage1 z we c secure an accuracy v gratify+ to a workman :o believes 9 precision4 ,= draw+ circles on metal1 b> compasses are mu* ! be/1 z !y are almo/ entirely free f spr+1 :i* att5ds ! jo9t$ compass4 ,to make 7because !y _c be b\ght7 su* an in/rum5t1 take a piece ( flat /eel1 "o-eigh? by ?ree-eigh?s ( an in* & sev5 in*es long1 & aft] turn+ & smoo?+ x c>efully1 make a slide half an in* wide1 z %[n at ,fig4 #ae1 ) a set-screw h on top to secure x at any po9t on ! b> ,e4 ,9 ! l[] "p ( ! slide ,f is plac$ a /eel tube l ,c1 %[n 9 ,figs4 #ab & #ad1 ) set-screw = hold+ po9ts l ,b ,b'1 ,fig4 #ac4 ,at ! opposite end ( ! b> ,e is plac$ a loop$ spr+ ,g1 :i* c>ries a /eel tube & po9t l ! spr+ ,d1 ,fig4 #ad4 ,above ?is tube & po9t1 %[n at j1 ,fig4 #ae1 is plac$ an adju/m5t screw k = f9e adju/m5t4 ,! inn] end ( ! screw k re/s aga9/ ! end ( ! b> ,e4 ,! t5d5cy ( ! spr+ ,g is to close ^u ! end ( ,e2 consequ5tly if we make use ( ! screw k to =ce away ! l[] end ( ,g1 we c set ! f9e po9t 9 j to ! greate/ exactness4 ,! spr+ ,g is made ( a piece ( /eel "o-eigh? ( an in* squ>e1 & secur$ to ! b> ,e ) a screw & /eady p9s at m4 ,a p5 & p5cil po9t atta*m5t c be add$ to ! spr+ ,g2 b 9 case ?is is done x w\ld be bett] to make ano!r spr+ l ,g )\t ! po9t j1 & ) ! adju/+ screw plac$ at l4 ,9 fitt+ p5 & p5cil po9ts to a spr+ l ,g x w\ld probably be economical to make !m outright2 t is1 make ! blades & screw = ! rul+ p5 & a spr+ or clamp+ tube = ! p5cil po9t4 ,,consid]ation ,,( ,,deta*$ ,,lev] ,,escapem5t ,,resum$4 ,we w n[1 ) our improv$ draw+ in/rum5ts1 resume ! consid]ation ( ! rat*et-too? lev] escapem5t4 ,we reproduce at ,fig4 #af a portion ( diagram ,,iii1 f ,moritz ,grossmann's ,prize ,essay on ! ,deta*$ ,lev] ,escapem5t1 9 ord] to po9t out ! error 9 del9eat+ ! entrance pallet to :i* we previ\sly call$ att5tion4 ,! cut1 z we give x1 is n q "o-half ! size ( ,mr4 ,grossmann's orig9al plate4 ,9 ! cut we give ! lett]s ( ref]5ce employ$ ! same z on ! orig9al engrav+1 except :]e we use o!rs 9 explanation4 ,! angul> motion ( ! lev] & pallet action z %[n 9 ! cut is t5 degrees2 b 9 our draw+1 :]e we only use eight & "o-half degrees1 ! same mi/ake w\ld give proportionate error if we did n take ! means to correct x4 ,! error to :i* we ref] lies 9 draw+ ! impulse face ( ! entrance pallet4 ,! impulse face ( ?is pallet z drawn by ,mr4 ,grossmann w\ld n1 f ! action ( ! engag+ too?1 c>ry ?is pallet ?r\gh m ?an eight degrees ( angul> motion2 consequ5tly1 ! too? :i* %\ld lock on ! exit pallet w\ld fail to d s1 & /rike ! impulse face4 ,we w\ld "h beg to add t no?+ w s mu* in/ruct a p]son desir+ to acquire s\nd ideas on escapem5ts z mak+ a l>ge model4 ,! writ] calls to m9d a wood model ( a lev] escapem5t made by "o ( ! boys 9 ! ,elg9 factory ab\t a ye> or two aft] ,mr4 ,grossmann's prize essay 0 publi%$4 ,x w5t f h& to h& & did mu* t[>d e/abli%+ s\nd ideas z reg>ds ! correct action ( ! lev] escapem5t 9 t notable conc]n4 ,if a horological /ud5t %\ld con/ruct a l>ge model on ! l9es laid d[n 9 ,mr4 ,grossmann's "w1 ! entrance pallet w\ld be faulty 9 =m & w\ld n prop]ly p]=m its functions4 ,:y8 p]haps says our read]4 ,9 reply let u analyze ! action ( ! too? ,b z x re/s on ! pallet ,a4 ,n[1 if we move ?is pallet ?r\gh an angul> motion ( "o & "o-half degrees on ! c5t] g 7:i* also repres5ts ! c5t] ( ! pallet /aff71 ! too? ,b is dis5gag$ f ! lock+ face & comm5ces to slide along ! impulse face ( ! pallet & drops1 t is1 falls f ! pallet1 :5 ! inn] angle ( ! pallet is rea*$4 ,illu/ration3 ,fig4 #af ,?is inn] angle1 z locat$ by ,mr4 ,grossmann1 is at ! int]section ( ! %ort arc i ) ! l9e g n1 :i* limits ! t5-degree angul> motion ( ! pallets4 ,if we c>efully /udy ! draw+1 we w see ! pallet has only to move ?r\gh eight degrees ( angul> motion ( ! pallet /aff = ! too? to escape1 because ! too? c]ta9ly mu/ be dis5gag$ :5 ! inn] angle ( ! pallet rea*es ! p]iph]al l9e a4 ,! true way to locate ! position ( ! inn] angle ( ! pallet1 is to measure d[n on ! arc i t5 degrees f its int]section ) ! p]iph]al l9e a & locate a po9t to :i* a l9e is drawn f ! int]section ( ! l9e g m ) ! radial l9e a c1 ?us def9+ ! inn] angle ( ! entrance pallet4 ,we w "n ?is po9t ! po9t x4 ,x may n be amiss to say ! arc i is swept f ! c5t] g ?r\gh ! po9t u1 said po9t be+ locat$ t5 degrees f ! int]section ( ! radial a c ) ! p]iph]al l9e a4 ,x w be notic$ t ! inn] angle ( ! entrance pallet ,a seems to ext5d inw>d1 beyond ! radial l9e a j1 t is1 t[>d ! pallet c5t] g1 & gives ! appe>ance ( be+ mu* ?ick] ?an ! exit pallet ,a'2 b we w see on exam9ation t ! extreme angle x ( ! entrance pallet mu/ move on ! arc i &1 consequ5tly1 cross ! p]iph]al l9e a at ! po9t u4 ,if we measure ! impulse faces ( ! two pallets ,a ,a'1 we w f9d !m ne>ly alike 9 l9e> ext5t4 ,mr4 ,grossmann1 9 del9eat+ 8 exit pallet1 br+s ! extreme angle 7%[n at #d7 d[n to ! p]iph]y ( ! escape1 z %[n 9 ! draw+1 :]e x ext5ds beyond ! int]section ( ! l9e g f ) ! radial l9e a #c4 ,! correct =m = ! entrance pallet %\ld be to ! dott$ l9e z x y4 ,illu/ration3 ,fig4 #ag ,we h spok5 ( engag+ & dis5gag+ frictions2 we d n "k h[ we c bett] expla9 ?is t]m ?an by illu/rat+ ! idea ) a gr9d/one4 ,suppose two m5 are gr9d+ on ! same /one2 ea* has1 say1 a cold *isel to gr9d1 z %[n at ,fig4 #ag1 :]e ,g repres5ts ! gr9d/one & ,n ,n' ! cold *isels4 ,! gr9d/one is suppos$ to be revolv+ 9 ! direction ( ! arr[4 ,! *isels ,n & ,n' are bo? be+ gr\nd1 b ! *isel ,n' is be+ cut mu* ! m rapidly1 z ea* p>ticle ( grit ( ! /one z x cat*es on ! /eel causes ! *isel to hug ! /one & bite 9 deep] & deep]2 :ile ! *isel %[n at ,n is ?ru/ away by ! action ( ! grit4 ,n[1 friction ( any k9d is only a sort ( gr9d+ op]ation1 & ! same pr9ciples hold good4 ,,! ,,necessity ,,= ,,good ,,in/rum5ts4 ,x is to be hop$ ! read] :o int5ds to pr(it by ?is treatise has fitt$ up su* a pair ( divid]s z ^? we h describ$1 because x is only ) accurate in/rum5ts he c hope to produce draw+s on :i* any reliance c be plac$4 ,! draw+ ( a rat*et-too? lev] escapem5t ( eight & "o-half degrees pallet action w n[ be resum$4 ,9 ! draw+ at ,fig4 #ah is %[n a complete del9eation ( su* an escapem5t ) eight & "o-half degrees ( pallet action & equidi/ant lock+ faces4 ,x is1 ( c\rse1 und]/ood ! escape :eel is to be drawn t5 in*es 9 diamet]1 & t ! degree arcs %[n 9 ,fig4 #a w be us$4 ,we comm5ce by c>efully plac+ on ! draw+-bo>d a %eet ( pap] ab\t fifte5 in*es squ>e1 & !n v]tically ?r\gh ! c5t] draw ! l9e a' a''4 ,at "s conv5i5t position on ?is l9e is e/abli%$ ! po9t a1 :i* repres5ts ! c5t] ( ! escape :eel4 ,9 ?is draw+ x is n important t ! entire escape :eel be %[n1 inasmu* z we h really to d ) b a little ov] sixty degrees ( ! p]iph]y ( ! escape :eel4 ,) ! divid]s c>efully set at five in*es1 f a1 z a c5t]1 we sweep ! arc n n1 & f ! int]section ( ! p]p5dicul> l9e a' a'' ) ! arc n we lay (f on ea* side ?irty degrees f ! brass degree arc1 & ?r\gh ! po9ts ?us e/abli%$ are drawn ! radial l9es a b' & a d'4 ,illu/ration3 ,fig4 #ah ,! po9t on ! arc n :]e x int]sects ) ! l9e b' is t]m$ ! po9t b4 ,at ! int]section ( ! radial l9e a d' is e/abli%$ ! po9t d4 ,we take t5 & "o-half degrees 9 ! divid]s1 & f ! po9t b e/abli% ! po9t c1 :i* embraces ! arc ( ! escape :eel :i* is utiliz$ by ! pallet action4 ,?r\gh ! po9t b ! l9e h' h is drawn at "r angles to ! l9e a b'4 ,! l9e j j' is also drawn at "r angles to ! l9e a d' ?r\gh ! po9t d4 ,we n[ h an int]section ( ! l9es j drawn 9 common ) ! l9e a a' at ! po9t g1 said po9t indicat+ ! c5t] ( ! pallet action4 ,! divid]s are n[ set to embrace ! space betwe5 ! po9ts b & g on ! l9e h' h1 & ! arc f f is swept2 :i*1 9 pro( ( ! accuracy ( ! "w1 int]sects ! arc n at ! po9t d4 ,?is arc co9cides ) ! lock+ faces ( bo? pallets4 ,to lay out ! entrance pallet1 ! divid]s are set to five in*es1 & f g z a c5t] ! %ort arc o o is swept4 ,on ?is arc "o degree is laid (f bel[ ! l9e h' h1 & ! l9e g i drawn4 ,! space embrac$ betwe5 ! l9es h & i on ! arc f repres5ts ! lock+ face ( ! entrance pallet1 & ! po9t =m$ at ! int]section ( ! l9e g i ) ! arc f is call$ ! po9t p4 ,to give ! prop] lock to ! face ( ! pallet1 f ! po9t p z a c5t] is swept ! %ort arc r r1 & f its int]section ) ! l9e a b' twelve degrees are laid (f & ! l9e b s drawn1 :i* def9es ! lock+ face ( ! entrance pallet4 ,f g z a c5t] is swept ! arc c' c'1 int]sect+ ! arc n n at c4 ,on ?is arc 7c7 is locat$ ! inn] angle ( ! entrance pallet4 ,! divid]s are set to embrace ! space on ! arc c' betwe5 ! l9es g h' & g k4 ,) ?is space 9 ! divid]s "o leg is set at ! po9t c1 measur+ d[n on ! arc c' & e/abli%+ ! po9t t4 ,! po9ts p & t are !n connect$1 & ?us ! impulse face ( ! entrance pallet ,b is def9$4 ,f ! po9t t is drawn ! l9e t t'1 p>allel to ! l9e b s1 ?us def9+ ! inn] face ( ! entrance pallet4 ,,del9eat+ ,,! ,,exit ,,pallet4 ,to del9eate ! exit pallet1 sweep ! %ort arc u u 7f g z a c5t]7 ) ! divid]s set at five in*es1 & f ! int]section ( ?is arc ) ! l9e g j' set (f eight & "o-half degrees & draw ! l9e g l4 ,at "o degree bel[ ?is l9e is drawn ! l9e g m4 ,! space on ! arc f betwe5 ^! l9es def9es ! lock+ face ( ! exit pallet4 ,! po9t :]e ! l9e g m int]sects ! arc f is nam$ ! po9t x4 ,f ! po9t x is erect$ ! l9e x w1 p]p5dicul> to ! l9e g m4 ,f x z a c5t]1 & ) ! divid]s set at five in*es1 ! %ort arc y y is swept1 & on ?is arc are laid (f twelve degrees1 & ! l9e x z is drawn1 :i* l9e def9es ! lock+ face ( ! exit pallet4 ,next is tak5 t5 & "o-half degrees f ! brass degree-scale1 & f ! po9t d on ! arc n ! space nam$ is laid (f1 & ?us is e/abli%$ ! po9t v2 & f g z a c5t] is swept ! arc v' v' ?r\gh ! po9t v4 ,x w be evid5t on a little ?\ght1 t if ! too? ,a' impell$ ! exit pallet to ! position %[n1 ! out] angle ( ! pallet mu/ ext5d d[n to ! po9t v1 on ! arc v' v'2 consequ5tly1 we def9e ! impulse face ( ?is pallet by draw+ a l9e f po9t x to v4 ,to def9e ! out] face ( ! exit pallet1 we draw ! l9e v e p>allel to ! l9e x z4 ,!re are no set rules = draw+ ! g5]al =m ( ! pallet arms1 only to be gov]n$ by & con=m+ to ab\t :at we w\ld deem appropriate1 & to accord ) a s5se ( proportion & me*anical elegance4 ,rat*et-too? pallets are usually made 9 :at is t]m$ close pallets2 t is1 ! pallet jewel is set 9 a slot saw$ 9 ! /eel pallet arm1 :i* is und\bt$ly ! /ronge/ & mo/ s]viceable =m ( pallet made4 ,we %all next consid] ! rat*et-too? lev] escapem5t ) circul> pallets & t5 degrees ( pallet action4 ,,del9eat+ ,,circul> ,,pallets4 ,to del9eate circul> pallets = a rat*et-too? lev] escapem5t1 we proce$ v mu* z 9 ! =m] draw+1 by locat+ ! po9t ,a1 :i* repres5ts ! c5t] ( ! escape :eel1 at "s conv5i5t po9t1 & ) ! divid]s set at five in*es1 sweep ! arc m1 to repres5t ! p]iph]y ( ! escape :eel1 & !n draw ! v]tical l9e ,a ,b'1 ,fig4 #ai4 ,we 7z be=e7 lay (f ?irty degrees on ! arc m ea* side ( ! int]section ( said arc ) ! l9e ,a ,b'1 & ?us e/abli% on ! arc m ! po9ts a b1 & f ,a z a c5t] draw ?r\gh ! po9ts s e/abli%$ ! radial l9es ,a a' & ,a b'4 ,we erect f ! po9t a a p]p5dicul> to ! l9e ,a a1 &1 z previ\sly expla9$1 e/abli% ! pallet c5t] at ,b4 ,inasmu* z we are to employ circul> pallets1 we lay (f to ! left on ! arc m1 f ! po9t a1 five degrees1 said five degrees be+ half ( ! angul> motion ( ! escape :eel utiliz$ 9 ! pres5t draw+1 & ?us e/abli% ! po9t c1 & f ,a z a c5t] draw ?r\gh ?is po9t ! radial l9e ,a c'4 ,to ! "r ( ! po9t a we lay (f five degrees & e/abli% ! po9t d4 ,to illu/rate ! und]ly+ pr9ciple ( our circul> pallets3 ) "o leg ( ! divid]s set at ,b we sweep ?r\gh ! po9ts c a d ! arcs c'' a'' d''4 ,f ,b z a c5t]1 we cont9ue ! l9e ,b a to f1 & ) ! divid]s set at five in*es1 sweep ! %ort arc e e4 ,f ! int]section ( ?is arc ) ! l9e ,b f we lay (f "o & a half degrees & draw ! l9e ,b g1 :i* e/abli%es ! ext5t ( ! lock on ! entrance pallet4 ,x w be notic$ ! l9e> ext5t ( ! lock+ face ( ! entrance pallet is great] ?an t ( ! exit1 al?\gh bo? repres5t an angle ( "o & a half degrees4 ,really1 9 practice1 ?is discrepancy is ( little importance1 z ! same side-%ake 9 bank+ w\ld secure safety 9 ei!r case4 ,illu/ration3 ,fig4 #ai ,! fault we previ\sly po9t$ out1 ( ! g5]ally accept$ me?od ( del9eat+ a deta*$ lev] escapem5t1 is n z conspicu\s "h z x is :]e ! pallets are drawn ) equidi/ant lock+ faces2 t is1 ! inn] angle ( ! entrance pallet 7%[n at s7 does n h to be c>ri$ d[n on ! arc d' z f> to insure a cont9u\s pallet action ( t5 degrees1 z ) ! pallets ) equidi/ant lock+ faces4 ,/ill1 ev5 "h we h c>ri$ ! angle s d[n ab\t half a degree on ! arc d'1 to secure a safe lock on ! exit pallet4 ,,! ,,am\nt ,,( ,,lock4 ,if we /udy ! l>ge draw+1 :]e we del9eate ! escape :eel t5 in*es 9 diamet]1 x w readily be se5 t al?\gh we claim "o & a half degrees lock1 we really h only ab\t "o degree1 inasmu* z ! curve ( ! p]iph]al l9e m div]ges f ! l9e ,b f1 &1 z a consequ5ce1 ! absolute lock ( ! too? ,c on ! lock+ face ( ! entrance pallet ,e is b ab\t "o degree4 ,"u ^! conditions1 if we did n ext5d ! out] angle ( ! exit pallet at t d[n to ! p]iph]al l9e m1 we w\ld sc>cely secure "o-half a degree ( lock4 ,?is is true ( bo? pallets4 ,we mu/ c>ry ! pallet angles at r s n t d[n on ! circles c'' d' if we w\ld secure ! lock & impulse we claim2 t is1 "o & a half degrees lock & eight & a half degrees impulse4 ,n[1 :ile ! writ] is will+ to admit t a "o-degree lock 9 a s\nd1 well-made escapem5t is ample1 /ill he is n will+ to all[ ( a loos5ess ( draw+ to incorporate to ! ext5t ( "o degree 9 any me*anical matt] dem&+ su* extreme accuracy z ! p>ts ( a wat*4 ,x has be5 claim$ t su* defects c1 to a great ext5t1 be rem$i$ by sett+ ! escapem5t clos]2 t is1 by br++ ! c5t]s ( ! pallet /aff & escape :eel ne>] toge!r4 ,we hold t su* a c\rse is n me*anical &1 fur!r1 t !re is n ! slighte/ necessity = su* a policy4 ,,advantage ,,( ,,mak+ ,,l>ge ,,draw+s4 ,by mak+ ! draw+s l>ge1 z we h already sugge/$ & insi/$ ^u1 we c secure an accuracy closely approximat+ p]fection4 ,z1 = in/ance1 if we wi% to get a lock ( "o & a half degrees on ! lock+ face ( ! entrance pallet ,e1 we measure d[n on ! arc c'' f its int]section ) ! p]iph]al l9e m "o & a half degrees1 & e/abli% ! po9t r & ?us locate ! out] angle ( ! entrance pallet ,e1 s !re w really be "o & a half degrees ( lock2 & by measur+ d[n on ! arc d' t5 degrees f its int]section ) ! p]iph]al l9e m1 we locate ! po9t s1 :i* det]m9es ! position ( ! inn] angle ( ! entrance pallet1 & we "k = a c]ta9ty t :5 ?is inn] angle is fre$ f ! too? x w be aft] ! pallet 7&1 ( c\rse1 ! lev]7 has pass$ ?r\gh exactly t5 degrees ( angul> motion4 ,= locat+ ! inn] angle ( ! exit pallet1 we measure on ! arc d'1 f its int]section ) ! p]iph]al l9e m1 eight & a half degrees1 & e/abli% ! po9t n1 :i* locates ! position ( ?is inn] angle2 &1 ( c\rse1 "o & a half degrees add$ on ! arc d' indicates ! ext5t ( ! lock on ?is pallet4 ,su* draw+s n only enable u to !orize to extreme exactness1 b also give u proportionate measurem5ts1 :i* c be c>ri$ into actual con/ruction4 ,,! ,,club-,,too? ,,lev] ,,escapem5t4 ,we w n[ take up ! club-too? =m ( ! lev] escapem5t4 ,?is =m ( too? has 9 ! ,unit$ ,/ates & 9 ,switz]l& almo/ entirely sup]c$$ ! rat*et too?4 ,! pr9cipal reason = its f9d+ s mu* favor is1 we ?9k1 *iefly ow+ to ! fact t ?is =m ( too? is bett] able to /& ! manipulations ( ! able-bodi$ wat*mak]1 :o possesses m /r5g? ?an skill4 ,we w n pause n[1 h[ev]1 to consid] ! comp>ative m]its ( ! rat*et & club-too? =ms ( ! lev] escapem5t1 b leave ?is "p ( ! !me = discussion aft] we h giv5 full in/ructions = del9eat+ bo? =ms4 ,) ! rat*et-too? lev] escapem5t all ( ! impulse mu/ be d]iv$ f ! pallets1 b 9 ! club-too? escapem5t we c divide ! impulse planes betwe5 ! pallets & ! tee? to suit our fancy2 or p]haps x w\ld be bett] to say c>ry out !ories1 because we h x 9 our p[]1 9 ?is =m ( ! lev] escapem5t1 to indulge ourselves 9 _m *anges ( ! relations ( ! sev]al p>ts4 ,) ! rat*et too? ! pr9cipal *anges we c\ld make w\ld be f pallets ) equidi/ant lock+s to circul> pallets4 ,! club-too? escape :eel n only all[s ( circul> pallets & equidi/ant lock+s1 b we c divide ! impulse betwe5 ! pallets & ! tee? 9 su* a way z w c>ry out _m !oretical advantages :i*1 aft] a full k ( ! escapem5t action is acquir$1 w naturally sugge/ !mselves4 ,9 ! escapem5t %[n at ,fig4 #bj we h select$1 z a v excell5t example ( ?is =m ( too?1 circul> pallets ( t5 degrees =k action & t5 & a half degrees ( escape-:eel action4 ,x w be notic$ t ! pallets "h are comp>atively ?9 to ^? 9 g5]al use2 ?is condition is accompli%$ by d]iv+ ! pr9cipal "p ( ! impulse f driv+ planes plac$ on ! tee?4 ,z relates to ! escape-:eel action ( ! t5 & "o-half degrees1 :i* gives impulse to ! escapem5t1 five & "o-half degrees are utiliz$ by ! driv+ planes on ! tee? & five by ! impulse face ( ! pallet4 ,( ! t5 degrees ( =k action1 f\r & a half degrees relate to ! impulse face ( ! tee?1 "o & a half degrees to lock1 & f\r degrees to ! driv+ plane ( ! pallets4 ,9 del9eat+ su* a club-too? escapem5t1 we comm5ce1 z 9 =m] examples1 by fir/ assum+ ! c5t] ( ! escape :eel at ,a1 & ) ! divid]s set at five in*es sweep+ ! arc a a4 ,?r\gh ,a we draw ! v]tical l9e ,a ,b'4 ,on ! arc a a1 & ea* side ( its int]section ) ! l9e ,a ,b'1 we lay (f ?irty degrees1 z 9 =m] draw+s1 & ?r\gh ! po9ts s e/abli%$ on ! arc a a we draw ! radial l9es ,a b & ,a c4 ,f ! int]section ( ! radial l9e ,a b ) ! arc a we draw ! l9e h h at "r angles to ,a b4 ,:]e ! l9e h int]sects ! radial l9es ,a ,b' is locat$ ! c5t] ( ! pallet /aff1 z %[n at ,b4 ,inasmu* z we decid$ to let ! pallet utilize five degrees ( escape-:eel action1 we take a space ( two & a half degrees 9 ! divid]s1 & on ! arc a a lay (f ! said two & a half degrees to ! left ( ?is int]section1 & ?r\gh ! po9t s e/abli%$ draw ! radial l9e ,a g4 ,f ,b z a c5t] we sweep ! arc d d s x passes ?r\gh ! po9t ( int]section ( ! arc a ) ! l9e ,a g4 ,illu/ration3 ,fig4 #bj ,we aga9 lay (f two & a half degrees f ! int]section ( ! l9e ,a b ) ! arc a1 b ?is "t to ! "r ( said int]section1 & ?r\gh ! po9t s e/abli%$1 & f ,b z a c5t]1 we sweep ! arc e4 ,f ! int]section ( ! radial l9e ,a g ) ! arc a we lay (f to ! left five & a half degrees on said arc1 & ?r\gh ! po9t s e/abli%$ draw ! radial l9e ,a f4 ,) ! divid]s set at five in*es we sweep ! %ort arc m f ,b z a c5t]4 ,f ! int]section ( ! l9e h ,b h' ) ! arc m we lay (f on said arc & above ! l9e h' f\r & a half degrees1 & ?r\gh ! po9t s e/abli%$ draw ! l9e ,b j4 ,we next set ! divid]s s !y embrace ! space on ! radial l9e ,a b betwe5 its int]section ) ! l9e ,b j & ! c5t] ,a1 & f ,a z a c5t] sweep ! arc i1 said arc def9+ ! add5dum ( ! escape-:eel tee?4 ,we draw a l9e f ! int]section ( ! radial l9e ,a f ) ! arc i to ! int]section ( ! radial l9e ,a g ) ! arc a1 & ?us def9e ! impulse face ( ! escape-:eel too? ,d4 ,= def9+ ! lock+ face ( ! too? we draw a l9e at an angle ( tw5ty-f\r degrees to ! l9e ,a g1 z previ\sly describ$4 ,! back ( ! too? is def9$ ) a curve swept f "s po9t on ! add5dum circle i1 su* z our judgm5t w dictate4 ,9 ! draw+ %[n at ,fig4 #bj ! radius ( ?is curve 0 obta9$ by tak+ elev5 & a half degrees f ! degree arc ( #e radius 9 ! divid]s1 & sett+ "o leg at ! int]section ( ! radial l9e ,a f ) ! arc i1 & plac+ ! o!r on ! l9e i1 & all[+ ! po9t s e/abli%$ to s]ve z a c5t]1 ! arc 0 swept = ! back ( ! too?1 ! small circle at n d5ot+ "o ( ! c5t]s j describ$4 ,! l5g? = ! face ( ! too? 0 obta9$ by tak+ elev5 degrees f ! degree arc j ref]r$ to & lay+ t space (f on ! l9e p1 :i* def9$ ! face ( ! too?4 ,! l9e ,b k is laid (f "o & a half degrees bel[ ,b h on ! arc m4 ,! ext5t ( ?is arc on ! arc d def9es ! lock+ face ( ! entrance pallet4 ,we set (f f\r degrees on ! arc m bel[ ! l9e ,b k1 & ?r\gh ! po9t s e/abli%$ draw ! l9e ,b l4 ,we draw a l9e f ! int]section ( ! l9e ,a g ) ! l9e c h to ! int]section ( ! arc e ) ! l9e c l1 & def9e ! impulse face ( ! entrance pallet4 ,,relations ,,( ,,! ,,sev]al ,,p>ts4 ,be=e we proce$ to del9eate ! exit pallet ( our escapem5t1 let u reason on ! relations ( ! sev]al p>ts4 ,! club-too? lev] escapem5t is really ! mo/ complicat$ escapem5t made4 ,we mean by ?is t !re are m factors involv$ 9 ! problem ( design+ x correctly ?an 9 any o!r kn[n escapem5t4 ,mo/--we _h bett] say all1 = !re are no exceptions :i* occur to u--writ]s on ! lev] escapem5t lay d[n c]ta9 empirical rules = del9eat+ ! sev]al p>ts1 )\t giv+ reasons = ?is or t c\rse4 ,= illu/ration1 x is an e/abli%$ practice among escapem5t mak]s to employ tang5tial lock+s1 z we expla9$ & illu/rat$ 9 ,fig4 #af4 ,n[1 :5 we adopt circul> pallets & c>ry ! lock+ face ( ! entrance pallet ar\nd to ! left two & a half degrees1 ! true c5t] = ! pallet /aff1 if we employ tang5t lock+s1 w\ld be locat$ on a l9e drawn tang5t to ! circle a a f its int]section ) ! radial l9e ,a k1 ,fig4 #ba4 ,su* a tang5t is depict$ at ! l9e s l'4 ,if we reason on ! situation1 we w see t ! l9e ,a k is n at "r angles to ! l9e s l2 &1 consequ5tly1 ! lock+ face ( ! entrance pallet ,e has n really ! twelve-degree lock we are taught to believe x has4 ,illu/ration3 ,fig4 #ba ,we w n discuss ^! m9or po9ts fur!r at pres5t1 b leave !m = subsequ5t consid]ation4 ,we w say1 h[ev]1 t we c\ld locate ! c5t] ( ! pallet action at ! small circle ,b' above ! c5t] ,b1 :i* we h select$ z our =k-&-pallet action1 & secure a p]fectly s\nd escapem5t1 ) sev]al claim$ advantages4 ,let u n[ take up ! del9eation ( ! exit pallet4 ,x is v easy to locate ! out] angle ( ?is pallet1 z ?is mu/ be situat$ at ! int]section ( ! add5dum circle i & ! arc g1 & locat$ at o4 ,x is also self-evid5t t ! inn] or lock+ angle mu/ be situat$ at "s po9t on ! arc h4 ,to det]m9e ?is location we draw ! l9e ,b c f ,b 7! pallet c5t]7 ?r\gh ! int]section ( ! arc h ) ! pit* circle a4 ,aga91 x foll[s z a self-evid5t fact1 if ! pallet we are deal+ ) 0 lock$1 t is1 engag$ ) ! too? ,d''1 ! inn] angle n ( ! exit pallet w\ld be "o & a half degrees inside ! pit* circle a4 ,) ! divid]s set at #e1 we sweep ! %ort arc b b1 & f ! int]section ( ?is arc ) ! l9e ,b c we lay (f t5 degrees1 & ?r\gh ! po9t s e/abli%$1 f ,b1 we draw ! l9e ,b d4 ,bel[ ! po9t ( int]section ( ! l9e ,b d ) ! %ort arc b b we lay (f "o & a half degrees1 & ?r\gh ! po9t ?us e/abli%$ we draw ! l9e ,b e4 ,,locat+ ,,! ,,inn] ,,angle ,,( ,,! ,,exit ,,pallet4 ,! int]section ( ! l9e ,b e ) ! arc h1 :i* we w t]m ! po9t n1 repres5ts ! location ( ! inn] angle ( ! exit pallet4 ,we h already expla9$ h[ we locat$ ! position ( ! out] angle at o4 ,we draw ! l9e n o & def9e ! impulse face ( ! exit pallet4 ,if we m5tally analyze ! problem 9 h&1 we w see t z ! exit pallet vibrates ?r\gh its t5 degrees ( arc ! l9e ,b d & ,b c *ange places1 & ! too? ,d'' locks "o & a half degrees4 ,to del9eate ! lock+ face ( ! exit pallet1 we erect a p]p5dicul> to ! l9e ,b e f ! po9t n1 z %[n by ! l9e n p4 ,f n z a c5t] we sweep ! %ort arc t t1 & f its int]section ) ! l9e n p we lay (f twelve degrees1 & ?r\gh ! po9t s e/abli%$ we draw ! l9e n u1 :i* def9es ! lock+ face ( ! exit pallet4 ,we draw ! l9e o o' p>allel ) n u & def9e ! out] face ( said pallet4 ,9 ,fig4 #ba we h n made any attempt to %[ ! full outl9e ( ! pallets1 z !y are del9eat$ 9 precisely ! same mann] z ^? previ\sly %[n4 ,we %all next describe ! del9eation ( a club-too? escapem5t ) pallets hav+ equidi/ant lock+ faces2 & 9 ,fig4 #bb we %all %[ pallets ) mu* wid] arms1 because1 9 ?is in/ance1 we %all d]ive m ( ! impulse f ! pallets ?an f ! tee?4 ,we d ?is to %[ ! horological /ud5t ! facility ) :i* ! club-too? lev] escapem5t c be manipulat$4 ,we wi% also to impress on 8 m9d ! facts t ! employm5t ( ?ick pallet arms & ?9 pallet arms dep5ds on ! tee? ( ! escape :eel = its effici5cy1 & t he mu/ h k en\gh ( ! pr9ciples ( action to tell at a glance on :at l9es ! escapem5t 0 con/ruct$4 ,suppose1 = illu/ration1 we get hold ( a wat* :i* has ?9 pallet arms1 or /ones1 if !y are expos$ pallets1 & ! escape 0 design$ = pallets ) ?ick arms4 ,!re is no sort ( t9k]+ we c d to give su* a wat* a good motion1 except to *ange ei!r ! escape :eel or ! pallets4 ,if we "k en\gh ( ! lev] escapem5t to set ab\t x ) skill & judgm5t1 ! matt] is soon put to rights2 b o!rwise we c look & squ9t1 op5 & close ! bank+s1 & t9k] ab\t till doomsday1 & ! wat* be none ! bett]4 ,,club-,,too? ,,lev] ,,) ,,equidi/ant ,,lock+ ,,faces4 ,9 draw+ a club-too? lev] escapem5t ) equidi/ant lock+1 we comm5ce1 z on =m] occasions1 by produc+ ! v]tical l9e ,a k1 ,fig4 #bb1 & e/abli%+ ! c5t] ( ! escape :eel at ,a1 & ) ! divid]s set at #e sweep ! pit* circle a4 ,on ea* side ( ! int]section ( ! v]tical l9e ,a k ) ! arc a we set (f ?irty degrees on said arc1 & ?r\gh ! po9ts s e/abli%$ draw ! radial l9es ,a b & ,a c4 ,f ! int]section ( ! radial l9e ,a b ) ! arc a lay (f ?ree & a half degrees to ! left ( said int]section on ! arc a1 & ?r\gh ! po9t s e/abli%$ draw ! radial l9e ,a e4 ,f ! int]section ( ! radial l9e ,a b ) ! arc a erect ! p]p5dicul> l9e f1 & at ! cross+ or int]section ( said l9e ) ! v]tical l9e ,a k e/abli% ! c5t] ( ! pallet /aff1 z indicat$ by ! small circle ,b4 ,f ,b z a c5t] sweep ! %ort arc l ) a #e radius2 & f ! int]section ( ! radial l9e ,a b ) ! arc a cont9ue ! l9e f until x crosses ! %ort arc l1 z %[n at f'4 ,lay (f "o & a half degrees on ! arc l bel[ its int]section ) ! l9e f'1 & f ,b z a c5t] draw ! l9e ,b i ?r\gh said int]section4 ,f ,b z a c5t]1 ?r\gh ! int]section ( ! radial l9e ,a b & ! arc a1 sweep ! arc g4 ,! space betwe5 ! l9es ,b f' & ,b i on ! arc g def9es ! ext5t ( ! lock+ face ( ! entrance pallet ,c4 ,! int]section ( ! l9e ,b f' ) ! arc g we d5om9ate ! po9t o1 & f ?is po9t z a c5t] sweep ! %ort arc p ) a #e radius2 & on ?is arc1 f its int]section ) ! radial l9e ,a b1 lay (f twelve degrees1 & ?r\gh ! po9t s e/abli%$1 f o z a c5t]1 draw ! radial l9e o m1 said l9e def9+ ! lock+ face ( ! entrance pallet ,c4 ,illu/ration3 ,fig4 #bb ,x w be se5 t ?is gives a positive draw ( twelve degrees to ! entrance pallet2 t is1 c\nt+ to ! l9e ,b f'4 ,9 ?is escapem5t z del9eat$ !re is p]fect tang5tial lock+4 ,if ! lock+ face ( ! entrance-pallet /one at ,c 0 made to con=m to ! radial l9e ,a b1 ! lock ( ! too? ,d at o w\ld be dead2 t is1 absolutely neutral4 ,! too? ,d w\ld press ! pallet ,c 9 ! direction ( ! arr[ x1 t[>d ! c5t] ( ! pallet /aff ,b1 ) no t5d5cy on ! "p ( ! pallet to turn on its axis ,b4 ,!oretically1 ! pallet ) ! lock+ face cut to co9cide ) ! l9e ,a b w\ld resi/ movem5t on ! c5t] ,b 9 ei!r direction indicat$ by ! d\ble-head$ arr[ y4 ,a pallet at ,c ) a circul> lock+ face made to con=m to ! arc g1 w\ld p]mit movem5t 9 ! direction ( ! d\ble-head$ arr[ y ) only me*anical ef=t en\gh to ov]come friction4 ,b x is evid5t on inspection t a lock+ face on ! l9e ,a b w\ld cause a retrograde motion ( ! escape :eel1 & consequ5t resi/ance1 if said pallet 0 mov$ 9 ei!r direction indicat$ by ! d\ble-head$ arr[ y4 ,precisely ! same conditions obta9 at ! po9t u1 :i* holds ! same relations to ! exit pallet z ! po9t o does to ! entrance pallet ,c4 ,,angul> ,,motion ,,( ,,escape ,,:eel ,,det]m9$4 ,! arc 7?ree & a half degrees7 ( ! circle a embrac$ betwe5 ! radial l9es ,a b & ,a e det]m9es ! angul> motion ( ! escape :eel utiliz$ by ! escape-:eel too?4 ,to e/abli% & def9e ! ext5t ( angul> motion ( ! escape :eel utiliz$ by ! pallet1 we lay (f sev5 degrees on ! arc a f ! po9t o & e/abli% ! po9t n1 & ?r\gh ! po9t n1 f ,b z a c5t]1 we sweep ! %ort arc n'4 ,n[ some:]e on ?is arc n' w be locat$ ! inn] angle ( ! entrance pallet4 ,) a c>efully-made draw+1 hav+ ! escape :eel #aj 9 diamet]1 x w be se5 t ! arc a sep>ates consid]ably f ! l9e1 ,b f' :]e x crosses ! arc n'4 ,x w be rememb]$ t :5 draw+ ! rat*et-too? lev] escapem5t a measurem5t ( eight & a half degrees 0 made on ! arc n' d[n f its int]section ) ! pit* circle1 & ?us ! inn] angle ( ! pallet 0 locat$4 ,9 ! pres5t in/ance ! add5dum l9e w becomes ! controll+ arc1 & x w be fur!r notic$ on ! l>ge draw+ t ! l9e ,b h at its int]section ) ! arc n' approa*es ne>] to ! arc w ?an does ! l9e ,b f' to ! pit* circle a2 consequ5tly1 ! inn] angle ( ! pallet %\ld n 9 ?is in/ance be c>ri$ d[n on ! arc n' s f> to correct ! error z 9 ! rat*et too?4 ,reason tells u t if we measure t5 degrees d[n on ! arc n' f its int]section ) ! add5dum circle w we mu/ def9e ! position ( ! inn] angle ( ! entrance pallet4 ,we "n ! po9t s e/abli%$ ! po9t r4 ,! out] angle ( ?is pallet is locat$ at ! int]section ( ! radial l9e ,a b ) ! l9e ,b i2 said int]section we "n ! po9t v4 ,draw a l9e f ! po9t v to ! po9t r1 & we def9e ! impulse face ( ! entrance pallet2 & ! angul> motion obta9$ f x z relates to ! pallet /aff embraces six degrees4 ,measur$ on ! arc l1 ! entire t5 degrees ( angul> motion is z foll[s3 ,two & a half degrees f ! impulse face ( ! too?1 & indicat$ betwe5 ! l9es ,b h & ,b f2 "o & a half degrees lock betwe5 ! l9es ,b f' & ,b i2 six degrees impulse f pallet face1 entrance betwe5 ! l9es ,b i & ,b j4 ,a ,,dep>ture ,,f ,,=m] ,,practices4 ,grossmann & ,britt51 9 all _! del9eations ( ! club-too? escapem5t1 %[ ! exit pallet z dis5gag$4 ,to v>y f ?is beat5 track we w draw our exit pallet z lock$4 ,!re are o!r reasons :i* prompt u to d ?is1 "o ( :i* is1 pupils are apt to fall into a rut & only le>n to d ?+s a c]ta9 way1 & t way j z !y are in/ruct$4 ,to illu/rate1 ! writ] has met sev]al /ud5ts ( ! lev] escapem5t :o c\ld make draw+s ( ei!r club or rat*et-too? escapem5t ) ! lock on ! entrance pallet2 b :5 requir$ to draw a pallet z illu/rat$ at ,fig4 #bc1 c\ld n d x correctly4 ,occasionally "o c\ld d x1 b ! in/ances 7 r>e4 ,a /ill great] pos] 0 to reque/ !m to del9eate a pallet & too? :5 ! action ( escap+ 0 "o-half or "o-?ird p]=m$2 & x is easy to und]/& t only by su* /udies ! ma/] workman c ?or\ghly compreh5d ! complications involv$ 9 ! club-too? lev] escapem5t4 ,,an ,,apt ,,illu/ration4 ,z an illu/ration3 ,two draughtsm51 employ$ by two compet+ wat* factories1 ea* designs a club-too? escapem5t4 ,we w fur!r suppose ! tra9s & ma9spr+ p[] us$ by ea* conc]n to be precisely alike4 ,b 9 practice ! escapem5t ( ! wat*es made by "o factory w\ld set1 t is1 if y /opp$ ! balance dead /ill1 ) ! p9 9 ! =k1 ! wat* w\ld n />t ( itself2 :ile ! escapem5t design$ by ! o!r draughtsman w\ld n set--/op ! balance dead z (t5 z y *oose1 ! wat* w\ld />t ( itself4 ,yet ev5 to exp]i5c$ workm5 ! escape :eels & pallets look$ exactly alike4 ,( c\rse1 !re 0 a diff]5ce1 & /ill none ( ! text-books make m5tion ( x4 ,= ! pres5t we w g on ) del9eat+ our exit pallet4 ,! prelim9>ies are ! same z ) =m] draw+s1 ! in/ructions = :i* we ne$ n repeat4 ,previ\s to draw+ ! exit pallet1 let u reason on ! matt]4 ,! po9t r 9 ,fig4 #bc is locat$ at ! int]section ( pit* circle a & ! radial l9e ,a c2 & ?is w also be ! po9t at :i* ! too? ,c w engage ! lock+ face ( ! exit pallet4 ,?is po9t likewise repres5ts ! advance angle ( ! engag+ too?4 ,n[ if we measure on ! arc k 7:i* repres5ts ! lock+ faces ( bo? pallets7 d[nw>d "o & a half degrees1 we e/abli% ! lock ( ! pallet ,e4 ,to get ?is "o & a half degrees def9$ on ! arc k1 we set ! divid]s at #e1 & f ,b z a c5t] sweep ! %ort arc i1 & f ! int]section ( ! arc i ) ! l9e ,b e we lay (f on said arc i "o & a half degrees1 & ?r\gh ! po9t s e/abli%$ draw ! l9e ,b f4 ,n[ ! space on ! arc k betwe5 ! l9es ,b e & ,b f def9es ! angul> ext5t ( ! lock+ face4 ,) ! divid]s set at #e & "o leg re/+ at ! po9t r1 we sweep ! %ort arc t1 & f ! int]section ( said arc ) ! l9e ,a c we draw ! l9e n p2 b 9 do+ s we ext5d x 7! l9e7 s t x int]sects ! l9e ,b f1 & at said int]section is locat$ ! inn] angle ( ! exit pallet4 ,?is int]section we w "n ! po9t n4 ,illu/ration3 ,fig4 #bc ,f ! int]section ( ! l9e ,b e ) ! arc i we lay (f two & a half degrees on said arc1 & ?r\gh ! po9t s e/abli%$ we draw ! l9e ,b g4 ,! int]section ( ?is l9e ) ! arc k we "n ! po9t z4 ,) "o leg ( our divid]s set at ,a we sweep ! arc l s x passes ?r\gh ! po9t z4 ,?is la/ arc def9es ! add5dum ( ! escape-:eel tee?4 ,f ! po9t r on ! arc a we lay (f ?ree & a half degrees1 & ?r\gh ! po9t s e/abli%$ draw ! l9e ,a j4 ,,locat+ ,,! ,,out] ,,angle ,,( ,,! ,,impulse ,,planes4 ,! int]section ( ?is l9e ) ! add5dum arc l locates ! out] angle ( ! impulse planes ( ! tee?1 & we "n x ! po9t x4 ,f ! po9t r we lay (f on ! arc a sev5 degrees & e/abli% ! po9t v1 :i* def9es ! ext5t ( ! angul> motion ( ! escape :eel utiliz$ by pallet4 ,?r\gh ! po9t v1 f ,b z a c5t]1 we sweep ! %ort arc m4 ,x w be evid5t on a mom5t's reflection t ?is arc m mu/ repres5t ! pa? ( movem5t ( ! out] angle ( ! exit pallet1 & if we measure d[n t5 degrees f ! int]section ( ! arc l ) ! arc m1 ! po9t s e/abli%$ 7:i* we "n ! po9t s7 mu/ be ! exact position ( ! out] angle ( ! pallet dur+ lock+4 ,we h a measure ( t5 degrees on ! arc m1 betwe5 ! l9es ,b g & ,b h1 & by tak+ ?is space 9 ! divid]s & sett+ "o leg at ! int]section ( ! arc l ) ! arc m1 & measur+ d[n on m1 we e/abli% ! po9t s4 ,draw+ a l9e f po9t n to po9t s we def9e ! impulse face ( ! pallet4 ,,mak+ ,,an ,,escapem5t ,,model4 ,illu/ration3 ,fig4 #bd ,x is next propos$ we apply ! !ories we h be5 consid]+ & make an enl>g$ model ( an escapem5t1 z %[n at ,figs4 #bd & #be4 ,?is model is suppos$ to h an escape :eel "o-fif? ! size ( ! #aj "o we h be5 draw+4 ,9 ! accompany+ cuts are %[n only ! ma9 plate & bridges 9 full l9es1 :ile ! positions ( ! escape :eel & balance are indicat$ by ! dott$ circles ,i ,b4 ,! cuts are to no precise scale1 b 7 r$uc$ f a full-size draw+ = conv5i5ce 9 pr9t+4 ,we %all give exact dim5sions1 h[ev]1 s !re w be no difficulty 9 c>ry+ out our in/ructions 9 con/ruction4 ,illu/ration3 ,fig4 #be ,p]haps x w\ld be z well to give a g5]al description ( ! model be=e tak+ up ! details4 ,a r$uc$ side view ( ! complete model is giv5 at ,fig4 #bf4 ,9 ?is cut ! escapem5t model %[n at ,figs4 #bd & #be is sket*$ 9 a r\gh way at ,r1 :ile ,n %[s a glass cov]1 & ,m a wood5 base ( poli%$ oak or walnut4 ,?is base is recess$ on ! l[] side to receive an eight-day spr+ clock movem5t1 :i* supplies ! motive p[] = ! model4 ,?is base is recess$ on top to receive ! ma9 plate ,a1 ,fig4 #bd1 & also to hold ! glass %ade ,n 9 position4 ,! base ,m is #b high & #h diamet]4 ,! glass cov] ,n c h ei!r a high & sph]ical top1 z %[n1 or1 z mo/ p pref]1 a flatt5$ oval4 ,illu/ration3 ,fig4 #bf ,! ma9 plate ,a is ( h>d spr+ brass1 #a_/aj ?ick & #f 9 diamet]2 9 fact1 a simple disk ( ! size nam$1 ) slightly r\nd$ edges4 ,! top plate1 %[n at ,c1 ,figs4 #bd & #be1 is #a_/h ?ick & %ap$ z %[n4 ,?is plate 7,c7 is support$ on two pill>s 9 diamet] & #a high4 ,fig4 #be is a side view ( ,fig4 #bd se5 9 ! direction ( ! arr[ p4 ,! cock ,d is also ( #a_/h spr+ brass %ap$ z %[n1 & atta*$ by ! screw f & /eady p9s s s to ! top plate ,c4 ,! bridge ,f ,g c>ries ! top pivots ( escape :eel & pallet /aff1 & is %ap$ z %[n at ! full outl9e4 ,?is bridge is support$ on two pill>s high & 9 diamet]1 "o ( :i* is %[n at ,e1 ,fig4 #be1 & bo? at ! dott$ circles ,e ,e'1 ,fig4 #bd4 ,to lay out ! l[] plate we draw ! l9e a a s x passes ?r\gh ! c5t] ( ,a at m4 ,at #a4c f "o edge ( ,a we e/abli% on ! l9e a ! po9t d1 :i* locates ! c5t] ( ! escape :eel4 ,on ! same l9e a at #a4ae f d we e/abli% ! po9t b1 :i* repres5ts ! c5t] ( ! pallet /aff4 ,at ! di/ance ( #a4af f b we e/abli% ! po9t c1 :i* repres5ts ! c5t] ( ! balance /aff4 ,to locate ! pill>s ,h1 :i* support ! top plate ,c1 we set ! divid]s at #b4eh1 & f ! c5t] m sweep ! arc n4 ,f ! int]section ( ?is arc ) ! l9e a 7at r7 we lay (f on said arc n #b4a & e/abli% ! po9ts g g'1 :i* locate ! c5t] ( ! pill>s ,h ,h4 ,) ! divid]s set s "o leg re/s at ! c5t] m & ! o!r leg at ! po9t d1 we sweep ! arc t4 ,) ! divid]s set at #a4cc we e/abli% on ! arc t1 f ! po9t d1 ! po9ts e e'1 :i* locate ! position ( ! pill>s ,e ,e'4 ,! outside diamet] ( ! balance ,b is #c-e_/h ) ! rim #c_/af wide & #e_/af deep1 ) screws 9 ! rim 9 imitation ( ! ord9>y comp5sation balance4 ,speak+ ( a balance ( ?is k9d sugge/s to ! writ] ! tr\ble he exp]i5c$ 9 procur+ mat]ial = a model ( ?is k9d--= ! balance1 a patt]n _h to be made1 !n a ca/+ made1 !n a ma*9i/ turn$ ! ca/+ up1 z x 0 too l>ge = an ,am]ican la!4 ,a hairspr+ _h to be specially made1 inasmu* z a ma9spr+ 0 too %ort1 ! coils too op5 &1 m p>ticul>ly1 did n look well4 ,pallet jewels _h to be made1 & lapidi/s h usually poor ideas ( close measurem5ts4 ,pres5t-day conditions1 h[ev]1 w1 no d\bt1 enable ! workman to foll[ our in/ructions mu* m readily4 ,,mak+ ,,! ,,bridges4 ,9 case ! read] makes ! bridges ,c & ,f1 z %[n 9 ,fig4 #bg1 he %\ld locate small circles on !m to indicate ! position ( ! screws = secur+ ^! bridges to ! pill>s :i* support !m1 & also o!r small circles to indicate ! position ( ! pivot holes d b = ! escape :eel & pallet /aff4 ,9 practice x w be well to draw ! l9e a a ?r\gh ! c5t] ( ! ma9 plate ,a1 z previ\sly direct$1 & also e/abli% ! po9t d z !re9 direct$4 ,! pivot hole d' = ! escape :eel1 & also ! holes at e e & b1 are n[ drill$ 9 ! bridge ,f4 ,^! holes %\ld be ab\t #a_/af 9 diamet]4 ,! same siz$ hole is also drill$ 9 ! ma9 plate ,a at d4 ,we n[ place a nicely-fitt+ /eel p9 9 ! hole d' 9 ! bridge ,f & let x ext5d into ! hole d 9 ! ma9 plate4 ,we clamp ! bridge ,f to ,a s ! hole b comes c5tral on ! l9e a1 & us+ ! holes e e 9 ,f z guides1 drill or m>k ! correspond+ holes e' e' & b 9 ! ma9 plate = ! pill>s ,e ,e' & ! pallet /aff4 ,illu/ration3 ,fig4 #bg ,?is plan w insure ! escape :eel & pallet /aff be+ p]fectly upright4 ,! same c\rse pursu$ ) ! plate ,c w insure ! balance be+ upright4 ,! pill>s :i* support ! bridges are %ap$ z %[n at ,fig4 #bh1 :i* %[s a side view ( "o ( ! pill>s :i* support ! top plate or bridge ,c4 ,! ends are turn$ to 9 diamet] & ext5d half ?r\gh ! plate1 :]e !y are held by screws1 ! same z 9 ,am]ican movem5ts4 ,illu/ration3 ,fig4 #bh ,! pill>s 7l ,h7 c be rivet$ 9 ! l[] plate ,a1 b we ?9k mo/ workm5 w f9d x m satisfactory to employ screws1 z %[n at ,fig4 #bi4 ,! heads ( su* screws %\ld be ab\t #c_/h 9 diamet] & nicely r\nd$1 poli%$ & blu$4 ,we w\ld n advise jewel+ ! pivot holes1 because !re is b slight friction1 except to ! foot ( ! balance pivot1 :i* %\ld be jewel$ ) a plano-convex g>net4 ,illu/ration3 ,fig4 #bi ,,imitation ,,rubies ,,= ,,capp+ ,,! ,,top ,,pivots4 ,! top pivots to ! escape :eel %\ld be capp$ ) imitation rubies = appe>ance sake only1 lett+ ! cap sett+s be r$ gold1 or brass r$ gild$4 ,if real twelve-k>at gold is employ$ ! co/ w n be mu*1 z ! sett+s are only ab\t #c_/h across & c be turn$ v ?91 s !y w really conta9 b v little gold4 ,! reason :y we recomm5d imitation ruby cap jewels = ! upp] holes1 is t su* jewels are mu* m brilliant ?an any real /one we c get = a mod]ate co/4 ,besides1 !re is no we> on !m4 ,! pallet jewels are also be/ made ( glass1 z g>net or any r$ /one w look almo/ black 9 su* l>ge pieces4 ,r$ c>nelian has a sort ( brick-r$ color1 :i* has a *eap appe>ance4 ,!re is a new phosphorus glass us$ by optical in/rum5t mak]s :i* is int5sely h>d1 & if color$ ruby-r$ makes a beautiful pallet jewel1 :i* w af=d z mu* s]vice z if real /ones 7 us$2 !y are no *eap] ?an c>nelian pallets1 b mu* ri*] look+4 ,! prettie/ cap = ! balance is "o ( ^? foilback /ones 9 imitation ( a rose-cut diamond4 ,illu/ration3 ,fig4 #cj ,illu/ration3 ,fig4 #ca ,9 turn+ ! /affs x is ! be/ plan to use d\ble c5t]s1 b a piece ( ,/ubs /eel wire t w g into a ,no4 #dj wire *uck1 w answ]2 9 case su* wire is us$1 a brass collet mu/ be provid$4 ,?is w be und]/ood by inspect+ ,fig4 #cj1 :]e ,l repres5ts ! ,/ubs wire & ,b ,n ! brass collet1 ) ! balance seat %[n at k4 ,! escape-:eel arbor & pallet /aff c be made 9 ! same way4 ,! l[] end ( ! escape :eel pivot is made ab\t long1 s t a %ort piece ( brass wire c be screw$ ^u x1 z %[n 9 ,fig4 #ca1 :]e h repres5ts ! pivot1 ,a ! l[] plate1 & ! dott$ l9e at p ! brass piece screw$ on ! end ( ! pivot4 ,?is piece p is simply a %ort bit ( brass wire ) a female screw tapp$ into ! end1 :i* screws on to ! pivot4 ,an arm is atta*$ to p1 z %[n at ,t4 ,! idea is1 ! pieces ,t p act l a la! dog to convey ! p[] f "o ( ! pivots ( an old eight-day spr+ clock movem5t1 :i* is secur$ by screws to ! l[] side ( ! ma9 plate ,a4 ,! plan is illu/rat$ at ,fig4 #cb1 :]e l repres5ts pivot ( ! eight-day clock employ$ to run ! model4 ,c\nt+ ! escape-:eel pivot ( ! clock z "o1 we take ! ?ird pivot f ?is 9 ! clock tra91 plac+ ! movem5t s ?is po9t comes opposite ! escape-:eel pivot ( ! model1 & screw ! clock movem5t fa/ to ! l[] side ( ! plate ,a4 ,! p>ts ,t1 ,fig4 #cc1 are alike on bo? pivots4 ,illu/ration3 ,fig4 #cb ,illu/ration3 ,fig4 #cc ,,pr(itable ,,= ,,expla9+ ,,to ,a ,,cu/om]4 ,to fully appreciate su* a l>ge escapem5t model z we h be5 describ+1 a p]son mu/ see x ) its great balance1 ne>ly #d across1 fla%+ & sp>kl+ 9 ! %[ w9d[ 9 ! ev5+1 & ! brilliant imitation ruby pallets dipp+ 9 & out ( ! escape :eel4 ,a model ( ?is k9d is f> m attractive ?an if ! entire tra9 7 %[n1 ! my/]y ( ,:at makes x g8 be+ "o ( ! attractions4 ,su* a model is1 fur!r1 ( great value 9 expla9+ to a cu/om] :at y mean :5 y say ! escapem5t ( 8 wat* is out ( ord]4 ,any practical workman c easily make an ev5 #ajj extra 9 a ye> by mak+ use ( su* a model4 ,= expla9+ to cu/om]s an extra balance cock c be us$ to %[ h[ ! jewels 7hole & cap7 are arrang$4 ,:]e ! p>ts are z l>ge z !y are 9 ! model1 ! cu/om] c see & und]/& = himself :at is necess>y to be done4 ,x is n to be und]/ood t our advice to pur*ase ! jewels = an extra balance cock conflicts ) our recomm5d+ ! read] n to jewel ! holes ( 8 model4 ,! extra cock is to be %[n1 n = use1 & is employ$ solely = expla9+ to a cu/om] :at is requir$ :5 a pivot or jewel is f\nd to be brok54 ,,h[ ,,l>ge ,,screws ,,are ,,made4 ,! screws :i* hold ! plates 9 place %\ld h heads ab\t #c_/h 9 diamet]1 to be 9 proportion to ! scale on :i* ! balance & escape :eel are gott5 up4 ,!re is mu* 9 ! mann] 9 :i* ! screw heads are f9i%$ z reg>ds ! elegance ( su* a model4 ,a p]fectly flat head1 no matt] h[ highly poli%$1 does n look well1 nei!r does a flatt5$ conehead1 l ,fig4 #ce4 ,! be/ head = ?is purpose is a cupp$ head ) *amf]$ edges1 z %[n at ,fig4 #cd 9 v]tical section4 ,! c5t] b is gr\nd & poli%$ into a p]fect concave by means ( a metal ball4 ,! face1 betwe5 ! l9es a a1 is poli%$ dead flat1 & ! *amf]$ edge a c f9i%$ a trifle convex4 ,! flat surface at a is bright1 b ! concave b & *amf] at c are beautifully blu$4 ,= a gilt-edg$1 d\ble extra head1 ! *amf] at c c be snail$1 t is1 gr\nd ) a suitable lap be=e blu+1 l ! /em-w9d :eels on "s wat*es4 ,illu/ration3 ,fig4 #cd ,illu/ration3 ,fig4 #ce ,,fancy ,,scre:eads4 ,!re are two easy me?ods ( remov+ ! blue f ! flat "p ( ! scre:ead at a4 7#a7 ,make a special hold] = ! screw 9 ! end ( a cem5t brass1 z %[n at ,e1 ,fig4 #cf1 & :ile x is sl[ly revolv+ 9 ! la! t\* ! flat surface a ) a %>p5$ pegwood wet ) muriatic acid1 :i* dissolves ! blue coat+ ( oxide ( iron4 7#b7 ,! surface ( ! scre:ead is coat$ ) a v ?9 coat+ ( %ellac dissolv$ 9 alcohol & ?or\ghly dri$1 or a ?9 coat+ ( collodion1 :i* is also dri$4 ,! screw is plac$ 9 ! ord9>y poli%+ triangle & ! flat face at a poli%$ on a t9 lap ) diamant9e & oil4 ,9 poli%+ su* surfaces ! ?9ne/ possible coat+ ( diamant9e & oil is sme>$ on ! lap--9 fact1 only en\gh to dim ! surface ( ! t94 ,x is1 ( c\rse1 und]/ood t x is necess>y to move only next to no?+ ( ! mat]ial to re/ore ! poli% ( ! /eel4 ,! poli%+ ( ! o!r /eel p>ts is done precisely l any o!r /eel "w4 ,illu/ration3 ,fig4 #cf ,! regulator is ( ! ,h[>d patt]n4 ,! hairspr+ /ud is set 9 ! cock l ! ,elg9 ?ree-qu>t]-plate movem5t4 ,! ri*e/ f9i% = su* a model is fro/$ plates & bridges4 ,! fro/+ %\ld n be a f9e mat1 l a wat* movem5t1 b co>se-gra9$--9 fact1 ! gra9 ( ! fro/+ %\ld be proportionate to ! size ( ! movem5t4 ,! edges ( ! bridges & balance cock c be left smoo?4 ,! be/ process = fro/+ is by acid4 ,details = do+ ! "w w n[ be giv54 ,illu/ration3 ,fig4 #cg ,illu/ration3 ,fig4 #ch ,to d ?is fro/+ by acid nicely1 make a sieve by tack+ & glu+ f\r pieces ( ?9 wood toge!r1 to make a rectangul> box )\t a bottom4 ,f\r pieces ( cig>-box wood1 #h long by #a wide1 answ] fir/ rate4 ,we %[ at ,a ,a ,a ,a1 ,fig4 #cg1 su* a box z if se5 f above2 ) a side view1 z if se5 9 ! direction ( ! arr[ a1 at ,fig4 #ch4 ,a piece ( ,india musl9 is glu$ across ! bottom1 z %[n at ! dott$ l9es b b4 ,by turn+ up ! edges on ! outside ( ! box1 ! musl9 bottom c be drawn z tight z a drum head4 ,,h[ ,,to ,,d ,,acid ,,fro/+4 ,to d acid fro/+1 we procure two ounces ( gum ma/ic & place 9 ! squ>e sieve1 %[n at ,fig4 #cg4 ,usually m ?an half ! weight ( gum ma/ic is 9 f9e du/1 & if n1 t is1 if ! gum is 9 ! %ape ( small r\nd pellets call$ ma/ic te>s1 cru% ^! into du/ & place ! du/ 9 ,a4 ,let u next suppose we wi% to fro/ ! cock on ! balance1 %[n at ,fig4 #ci4 ,be=e we comm5ce to fro/1 ! cock %\ld be p]fectly f9i%$1 ) all ! holes made1 ! regulator cap 9 position1 ! screw hole made = ! ,h[>d regulator & ! index arc engrav$ ) ! lett]s ,s & ,f4 ,illu/ration3 ,fig4 #ci ,x is n necess>y ! brass %\ld be poli%$1 b e file m>k & scrat* %\ld be /on$ out ) a ,scot* /one2 9 fact1 be 9 ! condition kn[n z 9 ! gray4 ,x is n necess>y to fro/ any portion ( ! cock ,c1 except ! upp] surface4 ,to protect ! portion ( ! cock n to be fro/$1 l ! edges & ! back1 we /op out by pa9t+ ov] ) %ellac dissolv$ 9 alcohol1 to :i* a little lampblack is add$4 ,x is n necess>y ! coat+ ( %ellac %\ld be v ?ick1 b x is important x %\ld be well dri$4 ,,h[ ,,to ,,prep>e ,,! ,,surface4 ,= illu/ration1 let u suppose ! back & edges ( ! cock at ,fig4 #ci are coat$ ) %ellac & x is laid flat on a piece ( pap] ab\t a foot squ>e to cat* ! excess ( ma/ic4 ,holes %\ld be made 9 ?is pap] & also 9 ! bo>d on :i* ! pap] re/s to receive ! /eady p9s ( ! cock4 ,we hold ! sieve conta9+ ! ma/ic ov] ! cock &1 g5tly tapp+ ! box ,a ) a piece ( wood l a m$ium-siz$ file h&le1 %ake d[n a little sn[/orm ( ma/ic du/ ov] ! face ( ! cock ,c4 ,exactly h[ mu* ma/ic du/ is requir$ to produce a nice fro/+ is only to be det]m9$ by practice4 ,! way to obta9 ! knack is to fro/ a few scraps to get y\r h& 94 ,nitric acid ( full /r5g? is us$1 dipp+ ! piece into a %all[ di% = a few seconds4 ,a good-siz$ s\p plate w\ld answ] v nicely = fro/+ ! bottom plate1 :i*1 x w be rememb]$1 is #f 9 diamet]4 ,,h[ ,,to ,,et* ,,! ,,surface4 ,aft] ! ma/ic is sift$ on1 ! cock %\ld be heat$ up to ab\t #bej ,f41 to cause ! p>ticles ( ma/ic to adh]e to ! surface4 ,! philosophy ( ! process is1 ! nitric acid eats or dissolves ! brass1 leav+ a little brass isl& ! size ( ! p>ticle ( ma/ic :i* 0 atta*$ to ! surface4 ,aft] heat+ to atta* ! p>ticles ( ma/ic1 ! dipp+ 9 nitric acid is done z j describ$4 ,common comm]cial nitric acid is us$1 x n be+ necess>y to employ *emically pure acid4 ,= t matt]1 = su* purposes ! comm]cial acid is ! be/4 ,aft] ! acid has act$ = fifte5 or tw5ty seconds ! brass is r9s$ 9 pure wat] to remove ! acid1 & dri$ by patt+ ) an old s(t t[el1 & fur!r dri$ by wav+ ?r\gh ! air4 ,a little turp5t9e on a rag w remove ! ma/ic1 b turp5t9e w n t\* ! %ellac coat+4 ,! surface ( ! brass w be f\nd irregul>ly act$ ^u1 produc+ a sort ( mottl$ look4 ,to obta9 a nice fro/+ ! process ( apply+ ! ma/ic & et*+ mu/ be repeat$ ?ree or f\r times1 :5 a beautiful co>se-gra9 mat or fro/+ w be produc$4 ,! %ellac protection w n ne$ mu* pat*+ up dur+ ! ?ree or f\r bit+s ( acid1 z ! turp5t9e us$ to wa% (f ! ma/ic does n mu* affect ! %ellac coat+4 ,all ! screw holes l s s & d1 also ! /eady p9s on ! back1 are protect$ by v>ni%+ ) %ellac4 ,! edges ( ! cocks & bridges %\ld be poli%$ by rubb+ l5g?wise ) will[ *>coal or a bit ( *amois sk9 saturat$ ) oil & a little h>d r\ge scatt]$ ^u x4 ,! fro/+ ne$s ?or\gh scrat*-bru%+4 ,illu/ration3 ,fig4 #dj ,at ,fig4 #dj we %[ ! balance cock ( our model ) modifi$ =m ( ,h[>d regulator4 ,! regulator b> ,a & spr+ ,b %\ld be gr\nd smoo? on "o side & deeply outl9$ to p]fect =m4 ,! regulator cap ,c is cut out to ! correct size4 ,^! p>ts are ( dec>boniz$ ca/ /eel1 anneal$ until almo/ z s(t z %eet brass4 ,x is n s mu* "w to f9i% ^! p>ts z "o might imag9e4 ,let u take ! regulator b> = an example & c>ry x ?r\gh ! process ( mak+4 ,! /rip ( s(t %eet /eel on :i* ! regulator b> is outl9$ is repres5t$ by ! dott$ outl9e b1 ,fig4 #da4 ,illu/ration3 ,fig4 #da ,to cut out %eet /eel rapidly we take a piece ( smoo? clock ma9spr+ ab\t & #aj long & d\ble x toge!r1 s(t5+ ! b5d+ po9t ) ! lamp until ! piece ( ma9spr+ assumes ! =m %[n at ,fig4 #db1 :]e c repres5ts ! piece ( spr+ & ,h ,h ! b5*-vise jaws4 ,! piece ( s(t /eel is plac$ betwe5 ! limbs ( c c' ( ! old ma9spr+ up to ! l9e a1 ,fig4 #da1 & clamp$ 9 ! vise jaws4 ,! sup]flu\s /eel is cut away ) a %>p & r ?9 cold *isel4 ,illu/ration3 ,fig4 #db ,! *isel is pres5t$ z %[n at ,g1 ,fig4 #dc 7:i* is an end view ( ! vise jaws ,h ,h & regulator b>71 & held to cut obliquely & ) a sort ( %e>+ action1 z illu/rat$ 9 ,fig4 #db1 :]e ,a'' repres5ts ! s(t /eel & ,g ! cold *isel4 ,we might add t ,fig4 #db is a view ( ,fig4 #dc se5 9 ! direction ( ! arr[ f4 ,x is well to cut 9 f ! edge b on ! l9e d1 ,fig4 #da1 ) a saw1 9 ord] to readily break out ! surplus /eel & n b5d ! regulator b>4 ,by sett+ ! pieces ( /eel obliquely 9 ! vise1 or s ! l9e e comes ev5 ) ! vise jaws1 we c cut to m ne>ly con=m to ! circul> loop ,a'' ( ! regulator ,a4 ,illu/ration3 ,fig4 #dc ,! smoo? /eel surface ( ! b5t ma9spr+ c prev5ts ! vise jaws f m>k+ ! s(t /eel ( ! regulator b>4 ,a p]son :o has n tri$ ?is me?od ( cutt+ out s(t /eel w\ld n believe ) :at facility pieces c be %ap$4 ,any workman :o has a univ]sal face plate to 8 la! c turn out ! c5t] ( ! regulator b> to receive ! disk ,c1 & also turn out ! c5t] ( ! regulator spr+ ,b4 ,:at we h said ab\t ! regulator b> applies also to ! regulator spr+ ,b4 ,?is spr+ is atta*$ to ! cock ,d by means ( two small screws at n4 ,! micromet] screw ,f is tapp$ ?r\gh ,b'' z 9 ! ord9>y ,h[>d regulator1 & ! screw %\ld be ab\t ,no4 #f ( a ,swiss screw-plate4 ,! wire f :i* su* screw is made %\ld be #a_/aj 9 diamet]4 ,! /eel cap ,c is fitt$ l ! f9] =ms ( ,swiss wat*es4 ,! hairspr+ /ud ,e is ( /eel1 %ap$ z %[n1 & comes outl9$ ) ! o!r p>ts4 ,,to ,,temp] ,,& ,,poli% ,,/eel4 ,! regulator b> %\ld be h>d5$ by be+ plac$ 9 a fold$ piece ( %eet iron & heat$ r$ hot1 & ?r[n into cold wat]4 ,! regulator b> ,a ,a' is ab\t #c long2 & = hold+ x = h>d5+1 cut a piece ( ?9 %eet iron #b by #c & fold x ?r\gh ! middle l5g?wise1 z indicat$ by ! dott$ l9e g1 ,fig4 #dd4 ,! %eet iron :5 fold$ w appe> z %[n at ,fig4 #de4 ,a piece ( flat %eet metal ( ! same ?ickness z ! regulator b> %\ld be plac$ betwe5 ! iron leaves ,i ,i1 & ! leaves beat5 d[n ) a hamm]1 t ! iron may s]ve z a support = ! regulator dur+ heat+ & h>d5+4 ,a pa/e made ( ca/ile soap & wat] appli$ to ! regulator b> 9 ! iron envelope w protect x f oxidiz+ mu* dur+ ! heat+4 ,! portions ( ! regulator b> m>k$ h are int5d$ to be r\nd$1 :ile ! p>ts m>k$ m are int5d$ to be dead flat4 ,! r\nd+ is c>efully done1 fir/ ) a file & f9i%$ ) em]y pap]4 ,! out] edge ( ! loop ,a'' is a little r\nd$1 also ! inn] edge next ! cap ,c4 ,?is w be und]/ood by inspect+ ,fig4 #df1 :]e we %[ a magnifi$ v]tical section ( ! regulator on l9e l1 ,fig4 #dj4 ,! curvature %\ld embrace t portion ( ,a'' betwe5 ! radial l9es o o'1 & %\ld1 on ! model1 n measure m ?an #a_/dj4 ,x w be se5 t ! curv$ surface ( ! regulator is sunk s x meets only ! v]tical edge ( ! loop ,a''4 ,= ! av]age workman1 poli%+ ! flat p>ts m is ! mo/ difficult to d1 & = ?is reason we w give entire details4 ,x is to be expect$ t ! regulator b> w spr+ a little 9 h>d5+1 b if only a little we ne$ pay no att5tion to x4 ,illu/ration3 ,fig4 #dd ,illu/ration3 ,fig4 #de ,illu/ration3 ,fig4 #df ,,h[ ,,flat ,,/eel ,,poli%+ ,,is ,,done4 ,poli%+ a regulator b> = a l>ge model1 su* z we are build+1 is only a heavy job ( flat /eel "w1 a little l>g] b no m difficult ?an to poli% a regulator = a sixte5-size wat*4 ,we w\ld ask p]mission "h to say t really nice flat /eel "w is some?+ :i* only a comp>atively few workm5 c d1 &1 /ill1 ! process is q simple & ! accessories few & inexp5sive4 ,fir/1 gr\nd-glass slab #f by #f by 2 second1 flat z9c piece #c by #c by 2 ?ird1 a piece ( ?ick %eet brass #c by #b by #a_/h2 & a bottle ( ,vi5na lime4 ,! glass slab is only a piece ( plate glass cut to ! size giv5 above4 ,! z9c slab is pure z9c plan$ dead flat1 & ! glass gr\nd to a dead surface ) ano!r piece ( plate glass & "s m$ium f9e em]y & wat]1 ! :ole surface be+ gone ov] ) em]y & wat] until completely depoli%$4 ,! regulator b>1 aft] c>eful fil+ & dress+ up on ! edges ) an oil/one slip or a n>r[ em]y buff1 is f9i%$ z previ\sly describ$4 ,we w\ld add to ! details already giv5 a few words on poli%+ ! edges4 ,illu/ration3 ,fig4 #dg ,x is n necess>y t ! edges ( /eelwork1 l ! regulator b> ,b1 ,fig4 #dg1 %\ld be poli%$ to a flat surface2 inde$1 !y look bett] to be nicely r\nd$4 ,p]haps we c convey ! idea bett] by ref]r+ to c]ta9 p>ts3 say1 spr+ to ! regulator1 %[n at ,d1 ,fig4 #dj1 & also ! hairspr+ /ud ,e4 ,! edges ( ^! p>ts look be/ bevel$ 9 a r\nd$ mann]4 ,illu/ration3 ,fig4 #dh ,illu/ration3 ,fig4 #di ,x is a little difficult to convey 9 words :at is meant by r\nd$ mann]4 ,to aid 9 und]/&+ our mean+1 we ref] to ,figs4 #dh & #di1 :i* are transv]se sections ( ,d1 ,fig4 #ej1 on ! l9e f4 ,! edges ( ,d1 9 ,fig4 #dh1 are simply r\nd$4 ,!re are no rules = su* r\nd+--only good judgm5t & an eye = :at looks well4 ,! edges ( ,d z %[n 9 ,fig4 #di are m on ! bevel$ ord]4 ,9 smoo?+ & poli%+ su* edges1 an ord9>y jewel]'s /eel burni% c be us$4 ,illu/ration3 ,fig4 #ej ,,smoo?+ ,,& ,,poli%+4 ,! idea 9 smoo?+ & poli%+ su* edges is to get a fair gloss )\t mu* att5tion to p]fect =m1 inasmu* z x is ! flat surface d on top :i* produces ! impression ( f9e f9i%4 ,if ?is is flat & brilliant1 ! r\nd$ edges1 l g c c really h q an inf]ior poli% & /ill look well4 ,= produc+ ! flat poli% on ! upp] surface ( ! regulator b> ,b & spr+ ,d1 ! flat surface d1 ,figs4 #dh1 #di1 #ea & #eb1 we mu/ atta* ! regulator b> to a plate ( heavy brass1 z %[n at ,fig4 #dg1 :]e ,a repres5ts ! brass plate1 & ,b ! regulator b>1 arrang$ = gr9d+ & poli%+ flat4 ,illu/ration3 ,fig4 #ea ,illu/ration3 ,fig4 #eb ,= atta*+ ! regulator b> ,b to ! brass plate ,a1 a good plan is to cem5t x fa/ ) la! wax2 b a bett] plan is to make ! plate ,a ( heavy %eet iron1 some?+ ab\t #a_/h ?ick1 & secure ! two toge!r ) ?ree or f\r little cat*es ( s(t sold]4 ,x is to be und]/ood ! edges ( ! regulator b> or ! regulator spr+ are poli%$1 & all t rema9s to be done is to gr9d & poli% ! flat face4 ,two pieces a a ( ! same ?ickness z ! regulator b> are plac$ z %[n & atta*$ to ,a to prev5t rock+4 ,aft] ,b is securely atta*$ to ,a1 ! regulator %\ld be coat$ ) %ellac dissolv$ 9 alcohol & well dri$4 ,! object ( ?is %ellac coat+ is to keep ! angles =m$ at ! meet+ ( ! face & side clean 9 ! process ( gr9d+ ) oil/one du/ & oil4 ,! face ( ! regulator is n[ plac$ on ! gr\nd glass aft] sme>+ x ) oil & oil/one du/4 ,x requires b a v slight coat+ to d ! "w4 ,! gr9d+ is cont9u$ until ! requir$ surface is dead flat1 aft] :i* ! "w is wa%$ ) soap & wat] & ! %ellac dissolv$ away ) alcohol4 ,! f9al poli% is obta9$ on ! z9c lap ) ,vi5na lime & alcohol4 ,:]e la! cem5t is us$ = secur+ ! regulator to ! plate ,a1 ! alcohol us$ ) ! ,vi5na lime dissolves ! cem5t & sme>s ! /eel4 ,diamant9e & oil are ! be/ mat]ials = poli%+ :5 ! regulator b> is cem5t$ to ! plate ,a4 ,,k ,,t ,,is ,,mo/ ,,ess5tial4 ,! k mo/ important = a practical work+ wat*mak] to possess is h[ to get ! wat*es he has to repair 9 a %ape to give satisfaction to 8 cu/om]s4 ,no "o w dispute ! tru? ( ! above italicis$ /atem5t4 ,x is only :5 we seek to h limits set1 & def9e :at su* k %\ld consi/ (1 t disagreem5t occurs4 ,"o workman :o has read ,grossmann or ,sauni]1 or bo?1 w\ld insi/ on all wat*es be+ made to a c]ta9 /&>d1 &1 accord+ to _! ideas1 all su* lev] wat*es z we are n[ deal+ ) %\ld h club-too? escapem5ts ) equidi/ant lock+s1 t5 degrees lev] & pallet action1 ) "o & "o-half degrees lock & "o & "o-half degrees drop4 ,ano!r workman w\ld insi/ on circul> pallets1 8 judgm5t be+ bas$ *iefly on :at he _h read z /at$ by "s au?or4 ,n[ ! facts ( ! situation are t lev] escapem5ts v>y z made by diff]5t manufactur]s1 "o conc]n us+ circul> pallets & ano!r us+ pallets ) equidi/ant lock+s4 ,,:at ,a ,,workman ,,%\ld ,,"k ,,to ,,repair ,a ,,wat*4 ,"o escapem5t mak] w divide ! impulse equally betwe5 ! too? & pallet2 ano!r w give an excess to ! too?4 ,n[ :ile ^! matt]s dem& our att5tion 9 ! highe/ degree 9 a !oretical s5se1 /ill1 = su* "k h[s z c\nt 9 a work%op1 !y are ( b trivial importance 9 practice4 ,we propose to deal 9 detail ) ! !oretical consid]ation ( ?ick & ?9 pallets1 & dwell exhau/ively on circul> pallets & ^? ) equidi/ant lock+ faces2 b be=e we d s we wi% to impress on our read]s ! importance ( be+ able to free !mselves ( ! idea t all lev] escapem5ts %\ld con=m to ! rigid rules ( any dictum4 ,,educate ,,! ,,eye ,,to ,,judge ,,( ,,angul> ,,z ,,well ,,z ,,l9e> ,,ext5t4 ,= illu/ration3 ,x w\ld be easy to design a lev] escapem5t t w\ld h lock+ faces :i* 7 bas$ on ! idea ( employ+ nei!r sy/em1 b a compromise betwe5 ! two1 & /ill give a good1 s\nd action4 ,all workm5 %\ld le>n to e/imate accurately ! ext5t ( angul> motion1 s z to be able to judge correctly ( escapem5t actions4 ,x is n only necess>y to "k t a club-too? escapem5t %\ld h "o & "o-half degrees drop1 b ! eye %\ld be educat$1 s to speak1 z to be able to judge ( angul> z well z l9e> ext5t4 ,illu/ration3 ,fig4 #ec ,mo/ me*anics w e/imate ! size ( any object measur$ 9 in*es or p>ts ( in*es v closely2 b z reg>ds angul> ext5t1 except 9 a few in/ances1 we w f9d me*anics b indiff]5t judges4 ,to illu/rate1 let u ref] to ,fig4 #ec4 ,"h we h ! base l9e ,a ,a' & ! p]p5dicul> l9e a ,b4 ,n[ almo/ any p]son w\ld be able to see if ! angle ,a a ,b 0 equal to ,b a ,a'2 b n five 9 "o hundr$ practical me*anics w\ld be able to e/imate ) ev5 tol]able accuracy ! measure ! angles made to ! base by ! l9es b c d2 & /ill wat*mak]s are requir$ 9 ! daily practice ( _! craft to "w to angul> motions & movem5ts almo/ z important z to results z diamet]s4 ,:at is ! use ( our kn[+ t 9 !ory an escape-:eel too? %\ld h "o & "o-half degrees drop1 :5 9 reality x has ?ree degrees8 ,x is only by educat+ ! eye f c>efully-made draw+s2 or1 :at is bett]1 con/ruct+ a model on a l>ge scale1 t we c le>n to judge ( prop] proportion & relation ( p>ts1 especially z we h no conv5i5t tool = measur+ ! angul> motion ( ! =k or escape :eel4 ,nor is x important t we %\ld h1 if ! workman is ?or\ghly book$ up 9 ! pr9ciples involv$4 ,z we expla9$ e>ly 9 ?is treatise1 !re is no imp]ative necessity compell+ u to h ! pallets & =k move ?r\gh t5 degrees any m ?an n9e & "o-half degrees1 except t exp]i5ce has prov5 t t5 degrees is ab\t ! "r ?+ = good results4 ,9 ?is day1 :5 su* a l>ge p]c5tage ( lev] escapem5ts h expos$ pallets1 we c v readily manipulate ! pallets to mat* ! =k & roll] action4 ,= t matt]1 9 _m in/ances1 ) a faulty lev] escapem5t1 ! be/ way to g ab\t putt+ x to rights is to fir/ set ! =k & roll] s !y act correctly1 & !n br+ ! pallets to con=m to ! angul> motion ( ! =k s adju/$4 ,,=k ,,& ,,roll] ,,action4 ,al?\gh we c\ld say a good deal m ab\t pallets & pallet action1 /ill we ?9k x advisable to drop = ! pres5t ?is p>ticul> "p ( ! lev] escapem5t & take up =k & roll] action1 because1 z we h /at$1 frequ5tly ! =k & roll] are pr9cipally at fault4 ,9 consid]+ ! action & relation ( ! p>ts ( ! =k & roll]1 we w fir/ def9e :at is consid]$ necess>y to con/itute a good1 s\nd con/ruction :]e ! =k vibrates ?r\gh t5 degrees ( angul> motion & is suppos$ to be engag$ ) ! roll] by means ( ! jewel p9 = ?irty degrees ( angul> motion ( ! balance4 ,!re is no special reason :y ?irty degrees ( roll] action %\ld be employ$1 except t exp]i5ce 9 practical con/ruction has come to admit ?is z ab\t ! "r arc = wat*es ( ord9>y good1 s\nd con/ruction4 ,manufactur]s h made dep>tures f ?is /&>d1 b 9 almo/ e in/ance h f9ally come back to pretty ne> ^! proportions4 ,9 decid+ on ! l5g? ( =k & size ( roll]1 we fir/ decide on ! di/ance ap>t at :i* to place ! c5t] ( ! balance & ! c5t] ( ! pallet /aff4 ,^! two po9ts e/abli%$1 we h ! l5g? ( ! =k & diamet] ( ! roll] def9$ at once4 ,,h[ ,,to ,,f9d ,,! ,,roll] ,,diamet] ,,f ,,! ,,l5g? ,,( ,,! ,,=k4 ,to illu/rate1 let u imag9e ! small circles ,a ,b1 ,fig4 #ed1 to repres5t ! c5t] ( a pallet /aff & balance /aff 9 ! ord] nam$4 ,we divide ?is space into f\r equal p>ts1 z %[n1 & ! ?ird space w repres5t ! po9t at :i* ! pit* circles ( ! =k & roll] w int]sect1 z %[n by ! arc a & circle b4 ,n[ if ! l5g? ( ! radii ( ^! circles /& to ea* o!r z ?ree to "o1 & ! =k vibrates ?r\gh an arc ( t5 degrees1 ! jewel p9 engag+ su* =k mu/ rema9 9 contact ) said =k = ?irty degrees ( angul> motion ( ! balance4 ,illu/ration3 ,fig4 #ed ,or1 9 o!r words1 ! ratio ( angul> motion ( two mobiles act+ on ea* mu/ be 9 ! same ratio z ! l5g? ( _! radii at ! po9t ( contact4 ,if we desire to give ! jewel p91 or1 9 ord9>y horological phraseology1 h a great] arc ( roll] action1 we w\ld ext5d ! l5g? ( =k 7say7 to ! po9t c1 :i* w\ld be "o-fif? ( ! space betwe5 ,a & ,b1 & ! ratio ( =k to roll] action w\ld be f\r to "o1 & t5 degrees ( =k action w\ld give =ty degrees ( angul> motion to ! roll]--& su* escapem5ts h be5 con/ruct$4 ,,:y ,,?irty ,,degrees ,,( ,,roll] ,,action ,,is ,,ab\t ,,"r4 ,n[ we h two s\nd reasons :y we %\ld n ext5d ! arc ( vibration ( ! balance3 7a7 ,if !re is an advantage to be d]iv$ f a deta*$ escapem5t1 x w\ld surely be policy to h ! arc ( contact1 t is1 = ! jewel p9 to engage ! =k1 z %ort an arc z is compatible ) a s\nd action4 7b7 ,x w be evid5t to any ?9k+ me*anic t ! act+ =ce ( a =k :i* w\ld c>ry ! jewel p9 aga9/ ! =ce ex]t$ by ! balance spr+ ?r\gh an arc ( fifte5 degrees1 or half ( an arc ( ?irty degrees1 w\ld fail to d s ?r\gh an arc ( tw5ty degrees1 :i* is ! condition impos$ :5 we adopt =ty degrees ( roll] action4 ,= ! pres5t we w accept ?irty degrees ( roll] action z ! /&>d4 ,be=e we proce$ to del9eate our =k & roll] we w devote a brief consid]ation to ! size & %ape ( a jewel p9 to p]=m well4 ,9 ?is matt] !re has be5 a broad field gone ov]1 bo? !oretically & 9 practical con/ruction4 ,wide jewel p9s1 r\nd jewel p9s1 oval jewel p9s h be5 employ$1 b practical con/ruction has n[ pretty well settl$ on a r\nd jewel p9 ) ab\t two-fif?s cut away4 ,& z reg>ds size1 if we adopt ! l9e> ext5t ( f\r degrees ( =k or twelve degrees ( roll] action1 we w f9d x ab\t "r4 ,,h[ ,,to ,,set ,a ,,=k ,,& ,,roll] ,,action ,,"r4 ,z previ\sly /at$1 frequ5tly ! true place to beg9 to set a lev] escapem5t "r is ) ! roll] & =k4 ,b to d ?is prop]ly we %\ld "k :5 su* =k & roll] action is "r & safe 9 all respects4 ,we w see on analysis ( ! actions involv$ t !re are ?ree important actions 9 ! =k & roll] functions3 7a7 ,! =k imp>t+ p]fect impulse ?r\gh ! jewel p9 to ! balance4 7b7 ,prop] unlock+ action4 7c7 ,safety action4 ,! la/ function is 9 mo/ in/ances sadly neglect$ &1 we regret to add1 by a l>ge majority ( ev5 practical workm5 x is v imp]fectly und]/ood4 ,9 mo/ ,am]ican wat*es we h ample opportunity af=d$ to inspect ! pallet action1 b ! =k & roll] action is plac$ s t rigid inspection is next to impossible4 ,! ,va*]on conc]n ( ,swiss manufactur]s 7 acute en\gh to see ! importance ( su* inspection1 & proce$$ to cut a circul> op5+ 9 ! l[] plate1 :i* p]mitt$1 on ! removal ( ! dial1 a c>eful scrut9y ( ! action ( ! roll] & =k4 ,:ile writ+ on ?is topic we w\ld sugge/ ! importance n only ( kn[+ h[ to draw a correct =k & roll] action1 b lett+ ! workman :o desires to be au fait 9 escapem5ts del9eate & /udy ! action ( a faulty =k & roll] action--say "o 9 :i* ! =k1 al?\gh ( ! prop] =m1 is too %ort1 or :at at fir/ glance w\ld appe> to am\nt to ! same ?+1 a roll] too small4 ,draw+s help wond]fully 9 reason+ out n only correct actions1 b also faulty ones1 & our read]s are e>ne/ly advis$ to make su* faulty draw+s 9 sev]al /ages ( action4 ,by ?is c\rse !y w educate ! eye to discrim9ate n only z to correct actions1 b also to detect ^? :i* are imp]fect1 & we believe mo/ wat*mak]s w admit t 9 _m in/ances x takes mu* long] to locate a fault ?an to rem$y x aft] x has be5 f\nd4 ,illu/ration3 ,fig4 #ee ,let u n[ proce$ to del9eate a =k & roll]4 ,x is n imp]ative t we %\ld draw ! p>ts to any scale1 b x is a rule among ,engli% mak]s to let ! di/ance betwe5 ! c5t] ( ! pallet /aff & ! c5t] ( ! balance /aff equal 9 l5g? ! *ord ( n9ety-six degrees ( ! pit* circle ( ! escape :eel1 :i*1 9 case we employ a pit* circle ( #e radius1 w\ld make ! di/ance betwe5 ,a & ,b1 ,fig4 #ee1 approximately #g1 :i* is a v fair scale = /udy draw+s4 ,,h[ ,,to ,,del9eate ,a ,,=k ,,& ,,roll]4 ,to arrive at ! prop] proportions ( ! sev]al p>ts1 we divide ! space ,a ,b into f\r equal p>ts1 z previ\sly direct$1 & draw ! circle a & %ort arc b4 ,) our divid]s set at #e1 f ,b z a c5t] we sweep ! %ort arc c4 ,f our arc ( sixty degrees1 ) a #e radius1 we take five degrees1 & f ! int]section ( ! "r l9e ,a ,b ) ! arc c we lay (f on ea* side five degrees & e/abli% ! po9ts d e2 & f ,b z a c5t]1 ?r\gh ^! po9ts draw ! l9es ,b d' & ,b e'4 ,n[ ! arc embrac$ betwe5 ^! l9es repres5ts ! angul> ext5t ( our =k action4 ,f ,a z a c5t] & ) our divid]s set at #e1 we sweep ! arc f4 ,f ! scale ( degrees we j us$ we lay (f fifte5 degrees on ea* side ( ! l9e ,a ,b on ! arc f1 & e/abli% ! po9ts g h4 ,f ,a z a c5t]1 ?r\gh ! po9ts j e/abli%$ we draw ! radial l9es ,a g' & ,a h'4 ,! angul> ext5t betwe5 ^! l9es def9es ! limit ( our roll] action4 ,n[ if we lay (f on ! arc f six degrees ea* side ( its int]section ) ! l9e ,a ,b1 we def9e ! ext5t ( ! jewel p92 t is1 on ! arc f we e/abli% ! po9ts l m at six degrees f ! l9e ,a ,b1 & ?r\gh ! po9ts l m draw1 f ,a z a c5t]1 ! radial l9es ,a l' & ,a m'4 ,! ext5t ( ! space betwe5 ! l9es ,a l' & ,a m' on ! circle a def9es ! size ( our jewel p94 ,,to ,,det]m9e ,,! ,,size ,,( ,a ,,jewel ,,p94 ,illu/ration3 ,fig4 #ef ,to make ! situation bett] und]/ood1 we make an enl>g$ draw+ ( ! l9es def9+ ! jewel p9 at ,fig4 #ef4 ,at ! int]section ( ! l9e ,a ,b ) ! arc a we locate ! po9t k1 & f x z a c5t] we sweep ! circle i s x passes ?r\gh ! int]section ( ! l9es ,a l' & ,a m' ) ! arc a4 ,we divide ! radius ( ! circle i on ! l9e ,a ,b into five equal p>ts1 z %[n by ! v]tical l9es j4 ,( ^! five spaces we assume ?ree z ! ext5t ( ! jewel p91 cutt+ away t portion to ! "r ( ! heavy v]tical l9e at k4 ,illu/ration3 ,fig4 #eg ,we w n[ proce$ to del9eate a =k & roll] z ! p>ts are relat$ on fir/ contact ( jewel p9 ) =k & initial ) ! comm5c+ ( ! act ( unlock+ a pallet4 ,! position & relations are also ! same z at ! close ( ! act ( impulse4 ,we comm5ce ! draw+ at ,fig4 #eg1 z be=e1 by draw+ ! l9e ,a ,b & ! arcs a & b to repres5t ! pit* circles4 ,we also sweep ! arc f to enable u to del9eate ! l9e ,a g'4 ,next 9 ord] we draw our jewel p9 z %[n at ,d4 ,9 draw+ ! jewel p9 we proce$ z at ,fig4 #ef1 except we let ! l9e ,a g'1 ,fig4 #eg1 assume ! same relations to ! jewel p9 z ,a ,b 9 ,fig4 #ef2 t is1 we del9eate ! jewel p9 z if ext5d+ on ! arc a six degrees on ea* side ( ! l9e ,a g'1 ,fig4 #eg4 ,,! ,,!ory ,,( ,,! ,,=k ,,action4 ,to aid u 9 reason+1 we e/abli% ! po9t m1 z 9 ,fig4 #ee1 at m1 ,fig4 #eg1 & proce$ to del9eate ano!r & imag9>y jewel p9 at ,d' 7z we %[ 9 dott$ outl9e74 ,a brief reason+ w %[ t 9 all[+ ?irty degrees ( contact ( ! =k ) ! jewel p91 ! c5t] ( ! jewel p9 w pass ?r\gh an arc ( ?irty degrees1 z %[n on ! arcs a & f4 ,n[ "h is an excell5t opportunity to impress on our m9ds ! true value ( angul> motion1 inasmu* z ?irty degrees on ! arc f is ( m ?an twice ! l9e> ext5t z on ! arc a4 ,be=e we comm5ce to draw ! horn ( ! =k engag+ ! jewel p9 ,d1 %[n at full l9e 9 ,fig4 #eg1 we w come to p]fectly und]/& :at me*anical relations are requir$4 ,z previ\sly /at$1 we assume ! jewel p91 z %[n at ,d1 ,fig4 #eg1 is 9 ! act ( enc\nt]+ ! inn] face ( ! horn ( ! =k = ! end or purpose ( unlock+ ! engag$ pallet4 ,n[ if ! inn] face ( ! horn ( ! =k 0 on a radial l9e1 su* radial l9e w\ld be p ,b1 ,fig4 #eg4 ,we repeat ?is l9e at p1 ,fig4 #ef1 :]e ! p>ts are drawn on a l>g] scale4 ,to del9eate a =k at ! in/ant ! la/ ef=t ( impulse has be5 imp>t$ to ! jewel p91 & said jewel p9 is 9 ! act ( sep>at+ f ! inn] face ( ! prong ( ! =k--we w\ld also call att5tion to ! fact t relations ( p>ts are precisely ! same z if ! jewel p9 _h j return$ f an excursion ( vibration & 0 9 ! act ( enc\nt]+ ! inn] face ( ! prong ( ! =k 9 ! act ( unlock+ ! escapem5t4 ,we m5tion$ ?is matt] previ\sly1 b v5ture on ! repetition to make ev]y?+ cle> & easily und]/ood4 ,we comm5ce by draw+ ! l9e ,a ,b & divid+ x 9 f\r equal p>ts1 z on previ\s occasions1 & f ,a & ,b z c5t]s draw ! pit* circles c d4 ,by me?ods previ\sly describ$1 we draw ! l9es ,a a & ,a a'1 also ,b b & ,b b' to repres5t ! angul> motion ( ! two mobiles1 viz41 =k & roll] action4 ,z already %[n1 ! roll] occupies twelve degrees ( angul> ext5t4 ,to get at ?is conv5i5tly1 we lay (f on ! arc by :i* we locat$ ! l9es ,a a & ,a a' six degrees above ! l9e ,a a & draw ! l9e ,a h4 ,n[ ! angul> ext5t on ! arc c betwe5 ! l9es ,a a & ,a h repres5ts ! radius ( ! circle def9+ ! jewel p94 ,f ! int]section ( ! l9e ,a a ) ! arc c z a c5t]1 & ) ! radius j nam$1 we sweep ! small circle ,d1 ,fig4 #eh1 :i* repres5ts our jewel p92 we aft]w>d cut away two-fif?s & draw ! full l9e ,d1 z %[n4 ,we %[ at ,fig4 #ei a portion ( ,fig4 #eh1 enl>g$ f\r times1 to %[ c]ta9 portions ( our del9eations m di/9ctly4 ,if we give ! subject a mom5t's consid]ation we w see t ! l5g? ( ! prong ,e ( ! lev] =k is limit$ to su* a l5g? z w all[ ! jewel p9 ,d to pass x4 ,,h[ ,,to ,,del9eate ,,! ,,prongs ,,( ,a ,,lev] ,,=k4 ,illu/ration3 ,fig4 #eh ,illu/ration3 ,fig4 #ei ,to del9eate ?is l5g?1 f ,b z a c5t] we sweep ! %ort arc f s x passes ?r\gh ! out] angle n1 ,fig4 #ei1 ( ! jewel p94 ,?is arc1 c>ri$ across ! jewel p9 ,d1 limits ! l5g? ( ! opposite prong ( ! =k4 ,! out] face ( ! prong ( ! =k c be drawn z a l9e tang5t to a circle drawn f ,a z a c5t] ?r\gh ! angle n ( ! jewel p94 ,su* a circle or arc is %[n at o1 ,figs4 #eh & #ei4 ,!re has be5 a good deal said z to :e!r ! out] edge ( ! prong ( a =k %\ld be /raight or curv$4 ,to ! writ]'s m9d1 a /raight-fac$ prong1 l f s to m1 is :at is requir$ = a =k ) a s+le roll]1 :ile a =k ) a curv$ prong w be be/ adapt$ = a d\ble roll]4 ,?is subject w be tak5 up aga9 :5 we consid] d\ble-roll] action4 ,! ext5t or l5g? ( ! out] face ( ! prong is also an op5 subject1 b z !re is b "o factor ( ! problem ( lev] escapem5t con/ruction dep5d+ on x1 :5 we "n ?is & see ?is requirem5t satisfi$ we h made an end ( ?is "q4 ,! function p]=m$ by ! out] face ( ! prong ( a =k is to prev5t ! engag$ pallet f unlock+ :ile ! gu>d p9 is opposite to ! pass+ holl[4 ,! inn] angle s ( ! horn ( ! =k mu/ be s %ap$ & locat$ t ! jewel p9 w j cle> x z x passes out ( ! =k1 or :5 x passes into ! =k 9 ! act ( unlock+ ! escapem5t4 ,9 escapem5ts ) solid bank+s a trifle is all[$1 t is1 ! =k is made en\gh %ort] ?an ! absolute !oretical l5g? to all[ = safety 9 ?is respect4 ,,! ,,prop] ,,l5g? ,,( ,a ,,lev]4 ,we w n[ see h[ long a lev] mu/ be to p]=m its functions p]fectly4 ,n[ let u det]m9e at :at po9t on ! inn] face ( ! prong ,e' ! jewel p9 p>ts f ! =k1 or engages on its return4 ,to d ?is we draw a l9e f ! c5t] r 7,fig4 #ei7 ( ! jewel p91 s z to meet ! l9e e at "r angles1 & ! po9t t s e/abli%$ on ! l9e e is :]e contact w take place betwe5 ! jewel p9 & =k4 ,x w be se5 ?is po9t 7t7 ( contact is "s di/ance back ( ! angle u :i* t]m9ates ! inn] face ( ! prong ,e'2 consequ5tly1 x w be se5 ! prongs ,e ,e' ( ! =k c ) safety be %ort5$ en\gh to af=d a safe +ress or egress to ! jewel p9 to ! slot 9 ! =k4 ,z reg>ds ! l5g? ( ! out] face ( ! prong ( ! =k1 a good rule is to make x "o & a half times ! diamet] ( ! jewel p94 ,! dep? ( ! slot ne$ be no m ?an to free ! jewel 9 its passage across ! t5 degrees ( =k action4 ,a conv5i5t rule z to ! dep? ( ! slot 9 a =k is to draw ! l9e k1 :i*1 x w be se51 co9cides ) ! circle :i* def9es ! jewel p94 ,,h[ ,,to ,,del9eate ,,! ,,safety ,,action4 ,illu/ration3 ,fig4 #fj ,we w next consid] a safety action ( ! s+le roll] type4 ,! active or necess>y p>ts ( su* safety action consi/ ( a roll] or disk ( metal1 usually /eel1 %ap$ z %[n 9 plan at ,a1 ,fig4 #fj4 ,9 ! edge ( ?is disk is cut 9 front ( ! jewel p9 a circul> recess %[n at a call$ ! pass+ holl[4 ,! rema9+ "p ( ! safety action is ! gu>d p9 %[n at ,n ,figs4 #fa & #fb1 :i* is plac$ 9 ! lev]4 ,n[ x is to be und]/ood t ! sole function p]=m$ by ! gu>d p9 is to /rike ! edge ( ! roll] ,a at any "t :5 ! =k />ts to unlock ! engag$ pallet1 except :5 ! jewel p9 is 9 ! slot ( ! =k4 ,to avoid extreme c>e 9 fitt+ up ! pass+ holl[1 ! horns ( ! =k are arrang$ to /rike ! jewel p9 & prev5t unlock+ 9 case ! pass+ holl[ is made too wide4 ,to del9eate ! safety action we fir/ draw ! =k & jewel p9 z previ\sly direct$ & z %[n at ,fig4 #fc4 ,! position ( ! gu>d p9 %\ld be z close to ! bottom ( ! slot ( ! =k z possible & be safe4 ,z to ! size ( ! gu>d p91 x is usual to make x ab\t "o-?ird or half ! diamet] ( ! jewel p94 ,! size & position ( ! gu>d p9 decid$ on & ! small circle ,n drawn1 to def9e ! size & position ( ! roll] we set our divid]s s t a circle drawn f ! c5t] ,a w j t\* ! edge ( ! small circle ,n1 & ?us def9e ! out] b\nd>y ( our roll]1 or roll] table1 z x is frequ5tly call$4 ,illu/ration3 ,fig4 #fa ,illu/ration3 ,fig4 #fb ,= decid+ ! angul> ext5t ( ! pass+ holl[ we h no fix$ rule1 b if we make x to occupy ab\t half m angul> ext5t on ! circle y ?an w co9cide ) ! angul> ext5t ( ! jewel p91 x w be p]fectly safe & effectual4 ,we previ\sly /at$ t ! jewel p9 %\ld occupy ab\t twelve degrees ( angul> ext5t on ! circle c1 & if we make ! pass+ holl[ occupy eighte5 degrees 7:i* is "o & a half ! angul> ext5t ( ! jewel p97 x w d nicely4 ,b if we %\ld ext5d ! wid? ( ! pass+ holl[ to tw5ty-f\r degrees x w\ld d no h>m1 z ! jewel p9 w\ld be well inside ! horn ( ! =k be=e ! gu>d p9 c\ld ent] ! pass+ holl[4 ,illu/ration3 ,fig4 #fc ,we %[ 9 ,fig4 #fa ! =k z sep>at$ f ! roll]1 b 9 ,fig4 #fb1 :i* is a side view1 we %[ ! =k & jewel p9 z engag$4 ,:5 draw+ a =k & roll] action x is safe to %[ ! gu>d p9 z if 9 actual contact ) ! roll]4 ,!n 9 actual con/ruction1 if ! p>ts are made to measure & agree ) ! draw+ 9 ! gray1 t is1 be=e poli%+1 ! process ( poli%+ w r$uce ! convex edge ( ! roll] en\gh to free x4 ,x is evid5t if ?\ght is giv5 to ! matt]1 t if ! gu>d p9 is entirely free & does n t\* ! roll] 9 any position1 a condition & relation ( p>ts exi/ :i* is all we c desire4 ,we are aw>e t x is usual to give a consid]able latitude 9 ?is respect ev5 by mak]s1 & all[ a good bit ( side %ake to ! lev]1 b our judgm5t w\ld condemn ! practice1 especially 9 high-grade wat*es4 ,,re/rict ,,! ,,frictional ,,surfaces4 ,grossmann1 9 8 essay on ! deta*$ lev] escapem5t1 adopts "o & a half degrees lock4 ,n[1 we ?9k t "o degree is ample2 & we are sure t e workman exp]i5c$ 9 ! con/ruction ( ! f9] wat*es w agree ) u 9 ! ass]tion t we %\ld 9 all in/ances seek to r$uce ! ext5t ( all frictional surfaces1 no matt] h[ well jewel$4 ,act+ "u su* advice1 if we c r$uce ! surface friction on ! lock f "o & a half degrees to "o degree or1 bett]1 to ?ree-f\r?s ( a degree1 x is surely wise policy to d s4 ,& z reg>ds ! ext5t ( angul> motion ( ! lev]1 if we r$uce ?is to six degrees1 exclusive ( ! lock1 we w\ld und\bt$ly obta9 bett] results 9 tim+4 ,we %all next consid] ! effects ( op5+ ! bank+s too wide1 & foll[ ) v>i\s conditions :i* are sure to come 9 ! exp]i5ce ( ! practical wat* repair]4 ,x is to be suppos$ 9 ?is problem t ! =k & roll] action is all "r4 ,! read] may say to ?is1 :y n close ! bank+8 ,9 reply we w\ld (f] ! supposition t "s workman _h b5t ! gu>d p9 =w>d or set a pallet /one too f> out4 ,we h n[ in/ruct$ our read]s h[ to draw & con/ruct a lev] escapem5t complete1 ( ! correct proportions1 & w next take up defective con/ruction & consid] faults exi/+ to a less] or great] degree 9 almo/ e wat*4 ,faults may also be ^? aris+ f repairs by "s workman n fully po/$ 9 ! correct =m & relation ( ! sev]al p>ts :i* g to make up a lev] escapem5t4 ,x makes no diff]5ce to ! artisan call$ ^u to put a wat* 9 p]fect ord] z to :om he is to attribute ! imp]fection1 mak] or =m] repair]2 all ! workman hav+ ! job 9 h& has to d is to "k positively t su* a fault actually exi/s1 & t x devolves ^u him to correct x prop]ly4 ,,be ,,fe>less ,,9 ,,repairs1 ,,if ,,sure ,,y ,,are ,,"r4 ,h5ce ! importance ( ! workman be+ p]fectly po/$ on su* matt]s &1 kn[+ t he is "r1 c g ahead & make ! wat* z x %\ld be4 ,! writ] _h an exp]i5ce ( ?is k9d ye>s ago 9 ,*icago4 ,a ,jules ,jurg5s5 wat* _h be5 9 ! h&s ( sev]al good workm5 9 t city1 b x w\ld /op4 ,x 0 !n br\ght to him ) a /atem5t ( facts giv5 above4 ,he knew !re mu/ be a fault some:]e & se>*$ = x1 & f\nd x 9 ! exit pallet--a c]ta9 too? ( ! escape :eel "u ! "r conditions w\ld sometimes n escape4 ,x might g ?r\gh a great _m ?\s& times & yet x might1 & did sometimes1 hold en\gh to /op ! wat*4 ,n[ probably mo/ ( my fell[-workm5 9 ?is in/ance w\ld h be5 afraid to alt] a ,jurg5s51 or ev5 h9t to ! own] t su* a ?+ c\ld exi/ z a fault 9 con/ruction 9 a wat* ( ?is ju/ly-celebrat$ mak]4 ,! writ] remov$ ! /one1 gr\nd a little f ! base ( ! (f5d+ pallet /one1 replac$ x1 & all tr\ble end$--no /ops f t on4 ,,/udy ,,( ,,an ,,escapem5t ,,error4 ,illu/ration3 ,fig4 #fd ,n[ let u suppose a case1 & imag9e a full-plate ,am]ican movem5t 9 :i* ! +ress or entrance pallet ext5ds out too f>1 & 9 ord] to h x escape1 ! bank+ on t side is op5$ too wide4 ,we %[ at ,fig4 #fd a draw+ ( ! p>ts 9 _! prop] relations "u ! conditions nam$4 ,x w be se5 by c>eful inspection t ! jewel p9 ,d w n ent] ! =k1 :i* is absolutely necess>y4 ,?is condition v frequ5tly exi/s 9 wat*es :]e a new pallet /one has be5 put 9 by an inexp]i5c$ workman4 ,n[ ?is is "o ( ! in/ances 9 :i* workm5 compla9 ( he>+ a scrap+ s\nd :5 ! wat* is plac$ to ! e>4 ,! rem$y1 ( c\rse1 lies 9 w>m+ up ! pallet arms & pu%+ ! /one 9 a trifle1 ,b h[ mu*8 say "s ( our read]s4 ,!re is no def9ite rule1 b we w tell su* qu]i/s h[ !y c te/ ! matt]4 ,remove ! hairspr+1 & aft] putt+ ! tra9 9 place & secur+ ! plates toge!r1 give ! w9d+ arbor a turn or two to put p[] on ! tra92 close ! bank+s well 9 s ! wat* _c escape on ei!r pallet4 ,put ! balance 9 place & screw d[n ! cock4 ,c>efully turn back ! bank+ on "o side s ! jewel p9 w j pass out ( ! slot 9 ! =k4 ,repeat ?is process ) ! opposite bank+2 ! jewel p9 w n[ pass out on ea* side4 ,be sure ! gu>d p9 does n int]f]e ) ! =k action 9 any way4 ,! =k is n[ 9 position to con=m to ! conditions requir$4 ,,h[ ,,to ,,adju/ ,,! ,,pallets ,,to ,,mat* ,,! ,,=k4 ,if ! escapem5t is all "r1 ! tee? w h "o & a half degrees lock & escape correctly2 b 9 ! in/ance we are consid]+1 ! /one w n p]mit ! tee? to pass1 & mu/ be pu%$ 9 until !y w4 ,x is n a v difficult matt] aft] we h plac$ ! p>ts toge!r s we c see exactly h[ mu* ! pallet protrudes beyond :at is necess>y1 to judge h[ f> to pu% x back :5 we h x out & heat$4 ,!re is /ill an if 9 ! problem we are consid]+1 :i* lies 9 ! fact t ! =k we are exp]im5t+ ) may be too %ort = ! jewel p9 to engage x = t5 degrees ( angul> motion4 ,?is condition a man ( l>ge exp]i5ce w be able to judge ( v closely1 b ! bett] plan = ! workman is to make = himself a te/ gage = ! angul> movem5t ( ! =k4 ,( c\rse x w be und]/ood t ) a =k :i* engages ! roll] = eight degrees ( =k action1 su* =k w n give good results ) pallets gr\nd = t5 degrees ( pallet action2 /ill1 9 _m in/ances1 a compromise c be effect$ :i* w give results t w satisfy ! own] ( a wat* ( mod]ate co/1 & f a f9ancial po9t ( view x /&s ! repair] 9 h& to d no m "w ?an is absolutely necess>y to keep him well pleas$4 ,we h j made m5tion ( a device = te/+ ! angul> motion ( ! lev]4 ,be=e we take up ?is matt]1 h[ev]1 we w devote a little "t & att5tion to ! subject ( jewel p9s & h[ to set !m4 ,we h h]et(ore only consid]$ jewel p9s ( "o =m1 t is1 a r\nd jewel p9 ) two-fif?s cut away4 ,we assum$ ?is =m f ! fact t exp]i5ce has demon/rat$ t x is ! mo/ practicable & effici5t =m s f> devis$ or appli$4 ,subsequ5tly we %all take up ! subject ( jewel p9s ( diff]5t %apes4 ,,h[ ,,to ,,set ,a ,,jewel ,,p9 ,,z ,,x ,,%\ld ,,be4 ,_m workm5 h a mortal t]ror ( sett+ a jewel p9 & seem to fancy t !y mu/ h a specially-devis$ in/rum5t = accompli%+ ?is end4 ,mo/ ,am]ican wat*es h ! hole = ! jewel p9 a _w too wide = x1 & we h he>d repeat$ compla9ts f ?is cause4 ,probably ! orig9al object ( ?is accommodat+ sort ( hole 0 to favor or obviate faults ( pallet action4 ,let u suppose1 = illu/ration1 t we h a roll] ) ! usual /yle ( hole = a jewel p9 :i* w take almo/ any?+ f ! size ( a ,no4 #ab sew+ ne$le up to a r\nd ,fr5* clock pallet4 ,illu/ration3 ,fig4 #fe ,we are re/rict$ z reg>ds ! prop] size ( jewel p9 by ! wid? ( ! slot 9 ! =k4 ,select+ a jewel :i* j fits ! =k1 we c set x z reg>ds its relation to ! /aff s x w cause ! pit* circle ( ! jewel p9 to co9cide ) ei!r ( dott$ circles a or a'1 ,fig4 #fe4 ,?is w p]haps be bett] und]/ood by ref]r+ to ,fig4 #ff1 :i* is a view ( ,fig4 #fe se5 9 ! direction ( ! arr[ c4 ,"h we see ! roll] jewel at ,d1 & if we br+ x =w>d z f> z ! hole 9 ! roll] w p]mit1 x w occupy ! position indicat$ at ! dott$ l9es2 & if we set x 9 7t[>d ! /aff7 z f> z ! hole w all[1 x w occupy ! position indicat$ by ! full outl9e4 ,illu/ration3 ,fig4 #ff ,n[ su* o!r condition might v easily exi/1 t br++ ! jewel p9 =w>d to ! position indicat$ by ! dott$ l9es at ,d1 ,fig4 #ff1 w\ld rem$y ! defect describ$ & illu/rat$ at ,fig4 #fd )\t any o!r *ange be+ necess>y4 ,we d n ass]t1 und]/&1 t a hole too l>ge = ! jewel p9 is ei!r necess>y or desirable--:at we wi% to convey to ! read] is ! necess>y k s t he c pr(it by su* a /ate if necess>y4 ,a hole :i* j fits ! jewel p9 s ! m]e/ film ( cem5t w hold x 9 place is ! way x %\ld be2 b we ?9k x w be "s "t be=e su* roll]s are made1 inasmu* z economy appe>s to be a *ief consid]ation4 ,,ab\t ,,jewel-,,p9 ,,sett]s4 ,to make a jewel-p9 sett] :i* w set a jewel p9 /raight is easy en\gh1 b to devise any su* in/rum5t :i* w set a jewel s z to p]fectly accord ) ! =k action is probably n practicable4 ,:at ! workman ne$s is to "k f exam9ation :5 ! jewel p9 is 9 ! prop] position to p]=m its functions correctly1 & he c only arrive at ?is k by c>eful /udy & ?\ght on ! matt]4 ,if we make up our m9ds on exam9+ a wat* t a jewel p9 is set too wide1 t is1 s x c>ries ! =k ov] too f> & increases ! lock to an undue degree1 take out ! balance1 remove ! hairspr+1 w>m ! roll] ) a small alcohol lamp1 & !n ) ! tweez]s move ! jewel p9 9 t[>d ! /aff4 ,illu/ration3 ,fig4 #fg ,illu/ration3 ,fig4 #fh ,illu/ration3 ,fig4 #fi ,illu/ration3 ,fig4 #gj ,no attempt %\ld be made to move a jewel p9 unless ! cem5t :i* holds ! jewel is s(t1 s t :5 ! p>ts cool (f ! jewel is z rigid z ev]4 ,a v little practice w enable any workman :o has ! necess>y delicacy ( t\* requisite to ev] become a good wat*mak]1 to manipulate a jewel p9 to 8 entire satisfaction ) no o!r sett] ?an a pair ( tweez]s & 8 eye1 ) a prop] k ( :at he wants to accompli%4 ,to prop]ly heat a roll] = tru+ up ! jewel p91 leave x on ! /aff1 & aft] remov+ ! hairspr+ hold ! balance by ! rim 9 a pair ( tweez]s1 fla%+ x back & =? ?r\gh ! flame ( a r small alcohol lamp until ! rim ( ! balance is s hot x c j be held betwe5 ! ?umb & f+]1 & :ile at ?is temp]ature ! jewel p9 c be press$ =w>d or backw>d1 z illu/rat$ 9 ,fig4 #ff1 & !n a t\* or two w set ! p9 /raight or p>allel ) ! /aff4 ,figs4 #fh & #fi are self-explanatory4 ,= cem5t+ 9 a jewel p9 a v conv5i5t tool is %[n at ,figs4 #fg & #gj4 ,x is made ( a piece ( copp] wire ab\t #a_/af 9 diamet]1 b5t to ! =m %[n at ,fig4 #fg4 ,! ends b b ( ! copp] wire are flatt5$ a little & recess$ on _! inn] faces1 z %[n 9 ,fig4 #gj1 to grasp ! edges ( ! roll] ,a4 ,! heat ( an alcohol lamp is appli$ to ! loop ( ! wire at g until ! small bit ( %ellac plac$ 9 ! hole h melts4 ,! necess>y small pieces ( %ellac are made by w>m+ a bit ( ! gum to ne> ! melt+ po9t & !n draw+ ! s(t5$ gum into a filam5t ! size ( horse hair4 ,a bit ( ?is brok5 (f & plac$ 9 ! hole h supplies ! cem5t necess>y to fa/5 ! jewel p94 ,figs4 #fh & #fi w1 no d\bt1 assi/ 9 a cle> und]/&+ ( ! matt]4 ,,h[ ,,to ,,make ,,an ,,angle-,,measur+ ,,device4 ,we w n[ resume ! consid]ation ( ! device = measur+ ! ext5t ( ! angul> motion ( ! =k & pallets4 ,n[1 be=e we take ?is matt] up 9 detail we wi% to say1 or r repeat :at we h said be=e1 :i* is to ! effect t t5 degrees ( =k & lev] action is n imp]ative1 z we c get j z s\nd an action & precisely z good results ) n9e & a half or ev5 n9e degrees z ) t51 if o!r act+ p>ts are 9 unison ) su* an arc ( angul> motion4 ,! *ief use ( su* an angle-measur+ device is to aid 9 comp>+ ! relative action ( ! sev]al p>ts ) a kn[n /&>d4 ,illu/ration3 ,fig4 #ga ,= use ) full-plate movem5ts ab\t ! be/ plan is a spr+ clip or clasp to embrace ! pallet /aff bel[ ! pallets4 ,we %[ at ,fig4 #ga su* a device4 ,to make x1 take a r l>ge size ( sew+ ne$le--! k9d kn[n z a mill9]'s ne$le is ab\t ! be/4 ,! diamet] ( ! ne$le %\ld be ab\t ,no4 #b1 s t at b we c drill & put 9 a small screw4 ,x is important t ! :ole affair %\ld be v light4 ,! l5g? ( ! ne$le %\ld be ab\t #a-e_/h1 9 ord] t f ! not* a to ! end ( ! ne$le ,a' %\ld be #a4 ,! ne$le %\ld be anneal$ & flatt5$ a little1 to give a pretty good grasp to ! not* a on ! pallet /aff4 ,good judgm5t is important 9 mak+ ?is clamp1 z x is ne>ly impossible to give exact measurem5ts4 ,ab\t #a_/dj 9 wid? :5 se5 9 ! direction ( ! arr[ j w be f\nd to be ab\t ! "r wid?4 ,! spr+ ,b c be made ( a bit ( ma9spr+1 anneal$ & fil$ d[n to agree 9 wid? ) ! "p ,a4 ,9 connection ) ! device %[n at ,fig4 #ga we ne$ a movem5t-hold] to hold ! movem5t z ne>ly a con/ant height z possible above ! b5*4 ,! idea is1 :5 ! clamp ,a ,b is slipp$ on ! pallet /aff ! index h& ,a' w ext5d outw>d1 z %[n 9 ,fig4 #gb1 :]e ! circle ,c is suppos$ to repres5t ! top plate ( a wat*1 & ,a' ! index h&4 ,,h[ ,,! ,,angul> ,,motion ,,is ,,measur$4 ,illu/ration3 ,fig4 #gb ,fig4 #gb is suppos$ to be se5 f above4 ,x is evid5t t if we remove ! balance f ! movem5t %[n at ,c1 leav+ p[] on ! tra91 & ) an oil+ tool or hair broa* move ! lev] back & =?1 ! index h& ,a' w %[ 9 a magnifi$ mann] ! angul> motion ( ! lev]4 ,n[ if we provide an index arc1 z %[n at ,d1 we c measure ! ext5t ( su* motion f bank to bank4 ,illu/ration3 ,fig4 #gc ,illu/ration3 ,fig4 #gd ,to get up su* an index arc we fir/ make a /& z %[n at ,e ,f1 ,fig4 #gc4 ,! arc ,d is made to #a radius1 to agree ) ! index h& ,a'1 & is divid$ into twelve degree spaces1 six ea* side ( a z]o1 z %[n at ,fig4 #gd1 :i* is an enl>g$ view ( ! index ,d 9 ,fig4 #gb4 ,! index arc is atta*$ to a %ort bit ( wire ext5d+ d[n into ! support ,e1 & made adju/able z to height by ! set-screw l4 ,let u suppose ! index arc is adju/$ to ! index h& ,a'1 & we move ! =k z sugge/$2 y see ! h& w\ld %[ exactly ! arc pass$ ?r\gh f bank to bank1 & by mov+ ! /& ,e ,f we c arrange s ! z]o m>k on ! scale /&s 9 ! c5t] ( su* arc4 ,?is1 ( c\rse1 gives ! angul> motion f bank to bank4 ,z an exp]im5t1 let u close ! bank+s s !y arre/ ! =k at ! in/ant ! too? drops f ea* pallet4 ,if ?is arc is t5 degrees1 ! pallet action is z x %\ld be ) ! majority ( mod]n wat*es4 ,,te/+ ,,lock ,,& ,,drop ,,) ,,our ,,new ,,device4 ,let u try ano!r exp]im5t3 ,we c>efully move ! =k away f ! bank1 & if aft] ! index h& has pass$ ?r\gh "o & a half degrees ! =k flies ov]1 we "k ! lock is "r4 ,we repeat ! exp]im5t f ! opposite bank1 & 9 ! same mann] det]m9e if ! lock is "r on ! o!r pallets4 ,y see we h n[ ! means ( measur+ n only ! angul> motion ( ! lev]1 b ! angul> ext5t ( ! lock4 ,at fir/ glance "o w\ld say t if n[ we br+ ! roll] & =k action to co9cide & act 9 unison ) ! pallet action1 we w\ld be all "r2 & s we w\ld1 b frequ5tly ?is br++ ( ! roll] & =k to agree is n s easily accompli%$4 ,x is *iefly t[>d ?is end ! ,wal?am =k is made adju/able1 s x c be mov$ to or f ! roll]1 & also t we c all[ ! pallet arms to be mov$1 z we w try & expla94 ,z we set ! bank+s ! pallets are all "r2 b to te/ matt]s1 let u remove ! hairspr+ & put ! balance 9 place4 ,n[1 if ! jewel p9 passes 9 & out ( ! =k1 x is to be suppos$ ! =k & roll] action is all "r4 ,to te/ ! =k & roll] action we close ! bank+ a little on "o side4 ,if ! =k & jewel p9 are relat$ to ea* o!r z !y %\ld be1 ! jewel p9 w n pass out ( ! =k1 nor w ! engag$ too? drop f t pallet4 ,?is condition %\ld obta9 on bo? pallets1 t is1 if ! jewel p9 w n pass out ( ! =k on a giv5 bank ! too? engag$ on its pallet %\ld n drop4 ,we h n[ come to ! mo/ intricate & important problems :i* relate to ! lev] escapem5t4 ,h[ev]1 we promise our read]s t if !y w take ! pa9s to foll[ closely our elucidations1 to make ^! puzzles pla94 ,b we w>n !m t !y are no easy problems to solve1 b require good1 h>d ?9k+4 ,! readie/ way to ma/] ?is matt] is by means ( su* a model escapem5t z we h describ$4 ,) su* a model1 & ! pallets made to clamp ) small set-screws1 & roll] con/ruct$ s ! jewel p9 c\ld be set to or f ! /aff1 ?is matt] c be r$uc$ to object lessons4 ,b /udy ( ! due relation ( ! p>ts 9 good draw+s w also ma/] ! situation4 ,a ,,few ,,exp]im5ts ,,) ,,our ,,angle-,,measur+ ,,device4 ,9 us+ ! little in/rum5t = det]m9+ angul> motion t we h j describ$1 c>e mu/ be tak5 t ! spr+ clamp :i* embraces ! pallet /aff does n slip4 ,9 ord] to ?or\ghly und]/& ! me?ods ( us+ ?is angle-measur+ device1 let u take a fur!r lesson or two4 ,we consid]$ measur+ ! am\nt ( lock on ea* pallet1 & advis$ ! removal ( ! balance1 because if we left ! balance 9 we c\ld n readily tell exactly :5 ! too? pass$ on to ! impulse plane2 b if we t\* ! =k lightly ) an oil+ tool or a hair broa*1 mov+ x 7! =k7 c>efully away f ! bank & wat*+ ! arc indicat$ by ! h& ,a1 ,fig4 #gb1 we c det]m9e ) great exactness ! angul> ext5t ( lock4 ,! diagram at ,fig4 #ge illu/rates h[ ?is exp]im5t is conduct$4 ,we apply ! hair broa* to ! end ( ! =k ,m1 z %[n at ,l1 & g5tly move ! =k 9 ! direction ( ! arr[ i1 wat*+ ! h& ,a & note ! numb] ( degrees1 or p>ts ( degrees1 indicat$ by ! h& z pass$ ov] be=e ! too? is unlock$ & passes on to ! impulse plane & ! =k flies =w>d to ! opposite bank4 ,n[1 ! quick movem5t ( ! pallet & =k may make ! h& m>k m or less ( an arc on ! index ?an "o ( t5 degrees1 z ! grasp may slip on ! pallet /aff2 b ! arc indicat$ by ! sl[ movem5t 9 unlock+ w be correct4 ,illu/ration3 ,fig4 #ge ,by tak+ a piece ( %>p5$ pegwood & plac+ ! po9t 9 ! slot ( ! =k1 we c te/ ! =k to see if ! drop takes place mu* be=e ! lev] re/s aga9/ ! opposite bank4 ,z we h previ\sly /at$1 ! drop f ! pallet %\ld n take place until ! lev] almo/ re/s on ! bank+ p94 ,:at ! read] %\ld impress on 8 m9d is t ! lev] %\ld pass ?r\gh ab\t "o & a half degrees arc to unlock1 & ! rema9d] 7eight & a half degrees7 ( ! t5 degrees are to be devot$ to impulse4 ,b1 und]/&1 if ! impulse angle is only sev5 & a half degrees1 & ! jewel p9 acts 9 accordance ) ! rules previ\sly giv51 d n alt] ! pallet until y "k = c]ta9 y w ga9 by x4 ,an obs]vant workman w1 aft] a little practice1 be able to det]m9e ?is matt]4 ,we w next take up ! d\ble roll] & =k action1 & also consid] 9 _m ways ! effect ( less angles ( action ?an t5 degrees4 ,?is matt] n[ seems ( m importance1 f ! fact t we are desir\s to impress on our read]s t !re is no valid reason = adopt+ t5 degrees ( =k & roll] action ) ! table roll]1 except t ab\t ?is numb] ( degrees ( action are requir$ to secure a reliable safety action4 ,) ! d\ble roll]1 z l[ z six degrees =k & pallet action c be safely employ$4 ,9 =k & pallet actions bel[ six degrees ( angul> motion1 side-%ake 9 pivot holes becomes a dang]\s factor1 z w be expla9$ fur!r on4 ,x is p]fectly compreh5d+ ! action ( ! lev] escapem5t & !n be+ able to rem$y defects1 t con/itute ! ma/] workman4 ,,h[ ,,to ,,measure ,,! ,,angul> ,,motion ,,( ,,an ,,escape ,,:eel4 ,illu/ration3 ,fig4 #gf ,we c also make use ( our angle-te/+ device = measur+ our escape-:eel action1 by lett+ ! clasp embrace ! arbor ( ! escape :eel1 in/ead ( ! pallet /aff4 ,we set ! index arc z 9 our =m] exp]im5ts1 except we place ! movable index ,d1 ,fig4 #gf1 s t :5 ! engag$ too? re/s on ! lock+ face ( a pallet1 ! index h& /&s at ! extreme end ( our arc ( twelve degrees4 ,we next1 ) our po9t$ pegwood1 />t to move ! =k away f ! bank1 z be=e1 we look %>p & see ! index h& move backw>d a little1 indicat+ ! draw on ! lock+ face4 ,z soon z ! pallet rea*es ! impulse face1 ! h& ,a moves rapidly =w>d1 & if ! escapem5t is ( ! club-too? ord] & closely mat*$1 ! h& ,a w pass ov] t5 & a half degrees ( angul> motion be=e ! drop takes place4 ,illu/ration3 ,fig4 #gg ,we w w>n our read]s 9 advance1 t if !y make su* a te/+ device !y w be a/oni%$ at ! inaccuracy :i* !y w f9d 9 ! escapem5ts ( s-call$ f9e wat*es4 ,! lock1 9 _m in/ances1 in/ead ( be+ "o & a half degrees1 w (t5] be f\nd to be f two to f\r degrees1 & ! impulse d]iv$ f ! escape :eel1 z illu/rat$ at ,fig4 #gf1 w (t5 fall bel[ eight degrees4 ,su* wat*es w h a poor motion & tick l\d en\gh to keep a policeman awake4 ,trials ) actual wat*es1 ) su* a device z we h j describ$1 9 conjunction ) a c>eful /udy ( ! act+ p>ts1 especially if aid$ by a l>ge model1 su* z we h describ$1 w soon br+ ! /ud5t to a degree ( skill unkn[n to ! old-/yle workman1 :o1 if a poor escapem5t bo!r$ him1 w\ld b5d back ! bank+ p9s or wid5 ! slot 9 ! =k4 ,we hold t educat+ our repair workm5 up to a high k ( :at is requir$ to con/itute a high-grade escapem5t1 w h a b5eficial effect on manufactur]s4 ,:5 we wi% to apply our device to ! measurem5t ( ! escapem5t ( ?ree-qu>t]-plate wat*es1 we w require ano!r index h&1 ) ! grasp+ end b5t d[nw>d1 z %[n at ,fig4 #gg4 ,! idea ) ?is =m ( index h& is1 ! b5t-d[n jaws ,b'1 ,fig4 #gg1 grasp ! =k z close to ! pallet /aff z possible1 mak+ an all[ance = ! act+ c5t] by s plac+ ! index arc t ! h& ,a w read correctly on ! index ,d4 ,suppose1 = in/ance1 we place ! jaws ,b' inside ! pallet /aff1 we !n place ! index arc s ! h& reads to ! arc indicat$ by ! dott$ arc m1 ,fig4 #gh1 & if set outside ( ! pallet /aff1 read by ! arc o4 ,illu/ration3 ,fig4 #gh ,,h[ ,a ,,balance ,,controls ,,! ,,timekeep+ ,,( ,a ,,wat*4 ,we ?9k a majority ( ! f9e lev] escapem5ts made abroad 9 ?is day h :at is t]m$ d\ble-roll] safety action4 ,! *ief ga9s to be d]iv$ f ?is =m ( safety action are3 7#a7 ,r$uc+ ! arc ( =k & roll] action2 7#b7 r$uc+ ! friction ( ! gu>d po9t to a m9imum4 ,:ile x is entirely practicable to use a table roll] = hold+ ! jewel p9 ) a d\ble-roll] action1 /ill a dep>ture f t =m is desirable1 bo? = looks & because z mu* ( ! aggregate weight ( a balance %\ld be kept z f> f ! axis ( rotation z possible4 ,we might z well consid] "h z else:]e1 ! relation ! balance be>s to ! tra9 z a controll+ p[]4 ,/rictly speak+1 ! balance & hairspr+ are ! "t measur]s1 ! tra9 s]v+ only two purposes3 7a7 ,to keep ! balance 9 motion2 7b7 to classify & record ! numb] ( vibrations ( ! balance4 ,h5ce1 x is ( p>am\nt importance t ! vibrations ( ! balance %\ld be z untrammel$ z possible2 ?is is :y we urge r$uc+ ! arc ( connection betwe5 ! balance & =k to "o z brief z is consi/5t ) s\nd results4 ,) a d\ble-roll] safety action we c easily r$uce ! =k action to eight degrees & ! roll] action to tw5ty-f\r degrees4 ,inasmu* z satisfactory results 9 adju/m5t dep5d v mu* on ! p]fection ( con/ruction1 we %all n[ dwell to "s ext5t on ! necessity ( ! sev]al p>ts be+ made on correct pr9ciples4 ,= in/ance1 by r$uc+ ! arc ( engagem5t betwe5 ! =k & roll]1 we less5 ! duration ( any di/urb+ influ5ce ( escapem5t action4 ,to resume ! explanation ( :y x is desirable to make ! /aff & all p>ts ne> ! axis ( ! balance z light z possible1 we w\ld say x is ! mov+ portion ( ! balance :i* controls ! regul>ity ( ! int]vals ( vibration4 ,to illu/rate1 suppose we h a balance only #c_/h 9 diamet]1 b ( ! same weight z "o 9 an ord9>y eighte5-size movem5t4 ,we c readily see t su* a balance w\ld require b a v light hairspr+ to cause x to give ! usual #ah1jjj vibrations to ! h\r4 ,we c also und]/&1 aft] a little ?\ght1 t su* a balance w\ld ex]t z mu* break+ =ce on its pivots z a balance ( ! same weight1 b 9 diamet] act+ aga9/ a v mu* /rong] hairspr+4 ,!re is ano!r factor 9 ! balance problem :i* des]ves our att5tion1 :i* factor is atmosph]ic resi/ance4 ,?is increases rapidly 9 proportion to ! velocity4 ,,h[ ,,b>ometric ,,pressure ,,affects ,a ,,wat*4 ,! mo/ c>eful inve/igators 9 horological me*anics h decid$ t a balance mu* above #ge_/ajj 9 diamet]1 mak+ #ah1jjj vibrations p] h\r1 is n desirable1 because ( ! v>y+ atmosph]ic di/urbances z indicat$ by b>ometric pressure4 ,a balance ) all ( its weight z ne> ! p]iph]y z is consi/5t ) /r5g?1 is :at is to be desir$ = be/ results4 ,x is ! mov+ matt] compos+ ! balance1 pitt$ aga9/ ! ela/ic =ce ( ! hairspr+1 :i* we h to dep5d ^u = ! regul>ity ( ! timekeep+ ( a wat*1 & if we c take two gra9s' weight ( matt] f our roll] table & place !m 9 ! rim or screws ( ! balance1 s z to act to bett] advantage aga9/ ! hairspr+1 we h dispos$ ( ^! two gra9s s z to increase ! effici5cy ( ! controll+ p[] & n increase ! /ress on ! pivots4 ,illu/ration3 ,fig4 #gi ,we h d$uc$ f ! facts set =?1 two axioms3 7a7 ,t we %\ld keep ! weight ( our balance z mu* 9 ! p]iph]y z possible1 consi/5t ) due /r5g?2 7b7 avoid excessive size f ! di/urb+ effect ( ! air4 ,we %[ at ,a1 ,fig4 #gi1 ! %ape ( ! piece :i* c>ries ! jewel p94 ,z %[n1 x consi/s ( ?ree p>ts3 7#a7 ,! socket ,a1 :i* receives ! jewel p9 a2 7#b7 ! "p ,a'' & hole b1 :i* goes on ! balance /aff2 7#c7 ! c\nt]poise ,a'''1 :i* makes up = ! weight ( ! jewel socket ,a1 neck ,a' & jewel p94 ,?is c\nt]poise also makes up = ! pass+ holl[ ,c 9 ! gu>d roll] ,b1 ,fig4 #hj4 ,z ! piece ,a is always 9 ! same relation to ! roll] ,b1 ! poise ( ! balance mu/ always rema9 ! same1 no matt] h[ ! roll] action is plac$ on ! /aff4 ,we once saw a d\ble roll] ( ne>ly ! %ape %[n at ,fig4 #gi1 :i* _h a small gold screw plac$ at d1 evid5tly = ! purpose ( pois+ ! d\ble roll]s2 b1 to our ?9k+1 x 0 a sort ( hairsplitt+ h>dly wor? ! extra tr\ble4 ,roll]s = v f9e wat*es %\ld be pois$ on ! /aff be=e ! balance is plac$ ^u x4 ,illu/ration3 ,fig4 #hj ,we %all next give detail$ in/ructions = draw+ su* a d\ble roll] z w be adapt$ = ! l>ge model previ\sly describ$1 :i*1 z ! read] w rememb]1 0 = t5 degrees ( roll] action4 ,we w also po9t out ! necess>y *anges requir$ to make x adapt$ = eight degrees ( =k action4 ,we w\ld beg to urge aga9 ! advantages to be d]iv$ f con/ruct+ su* a model1 ev5 = workm5 :o h _h a long exp]i5ce 9 escapem5ts1 our ^w = x !y w discov] a great _m new wr9kles !y nev] dream$ ( previ\sly4 ,x is important t e practical wat*mak] %\ld ?or\ghly ma/] ! !ory ( ! lev] escapem5t & be able to compreh5d & und]/& at sight ! faults & errors 9 su* escapem5ts1 :i*1 9 ! e-day practice ( 8 pr(ession1 come to 8 notice4 ,9 no place is su* k m requir$ ?an 9 =k & roll] action4 ,we are l$ to say ! above *iefly = ! b5efit ( a class ( workm5 :o ?9k !re is a c]ta9 set ( rules :i*1 if !y c\ld be obta9$1 w\ld enable !m to set to rights any & all escapem5ts4 ,x is well to und]/& t no su* sy/em exi/s & t1 practically1 we mu/ make "o error balance ano!r2 & x is ! "k h[ to make su* faults & errors c\nt]act ea* o!r t enables "o workman to e>n m = himself or 8 employ] 9 two days ?an ano!r workman1 :o c file & drill z well z he c1 w e>n 9 a week4 ,,proportions ,,( ,,! ,,d\ble-,,roll] ,,escapem5t4 ,! proportion 9 size betwe5 ! two roll]s 9 a d\ble-roll] escapem5t is an op5 "q1 or1 at lea/1 mak]s seldom agree on x4 ,grossmann %[s1 9 8 "w on ! lev] escapem5t1 two sizes3 7#a7 ,half ! diamet] ( ! act+ roll]2 7#b7 two-?irds ( ! size ( ! act+ roll]4 ,! *ief fault urg$ aga9/ a small] safety roll] is1 t x necessitates long] horns to ! =k to c>ry out ! safety action4 ,long] horns mean m metal 9 ! lev]1 & x is ! conc$$ policy ( all rec5t mak]s to h ! =k & pallets z light z possible4 ,ano!r fault p]ta9+ to long horns is1 :5 ! horn does h to act z safety action1 a great] friction ensues4 ,9 all s\ndly-con/ruct$ lev] escapem5ts ! safety action is only call$ into use 9 exceptional cases1 & if ! wat* 0 ly+ /ill w\ld !oretically nev] be requir$4 ,:]e =k & pallets are pois$ on _! arbor1 pocket motion 7except torsional7 %\ld b v little affect ! =k & pallet action ( a wat*1 & torsional motion is some?+ seldom br\ght to act on a wat* to an ext5t to make x wor?y ( mu* consid]ation4 ,9 ! d\ble-roll] action :i* we %all consid]1 we %all adopt ?ree-fif?s ( ! pit* diamet] ( ! jewel-p9 action z ! prop] size4 ,n b :at ! proportions giv5 by ,grossmann w d good s]vice2 b we adopt ! proportions nam$ because x enables u to use a light =k1 & /ill ! friction ( ! gu>d po9t on ! roll] is b little m ?an :]e a gu>d roll] ( half ! diamet] ( ! act+ roll] is employ$4 ,! =k action we %all consid] at pres5t is t5 degrees1 b subsequ5tly we %all consid] a d\ble-roll] action 9 :i* ! =k & pallet action is r$uc$ to eight degrees4 ,we %all conceive ! play betwe5 ! gu>d po9t & ! safety roll] z "o degree1 :i* w leave half a degree ( lock rema9+ 9 action on ! engag$ pallet4 ,,!oretical ,,action ,,( ,,d\ble ,,roll] ,,consid]$4 ,9 ! draw+ at ,fig4 #ha we %[ a diagram ( ! action ( ! d\ble-roll] escapem5t4 ,! small circle at ,a repres5ts ! c5t] ( ! pallet /aff1 & ! "o at ,b ! c5t] ( ! balance /aff4 ,! radial l9es ,a d & ,a d' repres5t ! arc ( angul> motion ( =k action4 ,! circle b b repres5ts ! pit* circle ( ! jewel p91 & ! circle at c c ! p]iph]y ( ! gu>d or safety roll]4 ,! po9ts e/abli%$ on ! circle c c by int]section ( ! radial l9es ,a d & ,a d' we w d5om9ate ! po9ts h & h'4 ,x is at ^! po9ts ! end ( ! gu>d po9t ( ! =k w t]m9ate4 ,9 con/ruction1 or 9 del9eat+ = con/ruction1 we %[ ! gu>d en\gh %ort ( ! po9ts h h' to all[ ! =k an angul> motion ( "o degree1 f ,a z a c5t]1 be=e said po9t w\ld come 9 contact ) ! safety roll]4 ,illu/ration3 ,fig4 #ha ,we draw ?r\gh ! po9ts h h'1 f ,b z a c5t]1 ! radial l9es ,b g & ,b g'4 ,we measure ?is angle by sweep+ ! %ort arc i ) any ( ! radii we h us$ = arc measurem5t 9 =m] del9eations1 & f9d x to be a trifle ov] sixty degrees4 ,to give ourselves a practical object lesson1 let u imag9e t a real gu>d po9t re/s on ! circle c at h4 ,suppose we make a not* 9 ! gu>d roll] repres5t$ by ! circle c1 to admit su* imag9>y gu>d po9t1 & !n comm5ce to revolve ! circle c 9 ! direction ( ! arr[ j1 lett+ ! gu>d po9t re/ con/antly 9 su* not*4 ,:5 ! not* n 9 c has be5 c>ri$ ?r\gh ?irty degrees ( arc1 c\nt+ f ,b z a c5t]1 ! gu>d po9t1 z relates to ,a z a c5t]1 w\ld only h pass$ ?r\gh an arc ( five degrees4 ,we %[ su* a gu>d po9t & not* at o n4 ,9 fact1 if a jewel p9 0 set to engage ! =k on ! pit* circle b a1 ! escapem5t w\ld lock4 ,to obviate su* lock we wid5 ! not* n to ! ext5t indicat$ by ! dott$ l9es n'1 all[+ ! gu>d po9t to fall back1 s to speak1 into ! not* n1 :i* really repres5ts ! pass+ holl[4 ,x is n to be und]/ood t ! ext5d$ not* at n is correctly drawn z reg>ds position1 because :5 ! gu>d po9t 0 on ! l9e ,a f ! po9t o w\ld be 9 ! c5t] ( ! ext5d$ not*1 or pass+ holl[4 ,we %all next give ! details ( draw+ ! d\ble roll]1 b be=e do+ s we deem$ x important to expla9 ! action ( su* gu>d po9ts m fully ?an has be5 done h]et(ore4 ,,h[ ,,to ,,design ,a ,,d\ble-,,roll] ,,escapem5t4 ,we h already giv5 v desirable =ms = ! p>ts ( a d\ble-roll] escapem5t1 consequ5tly we %all n[ deal *iefly ) act+ pr9ciples z reg>ds ! roll]s1 b w give1 at ,fig4 #hb1 a v well proportion$ & practical =m ( =k4 ,! pit* circle ( ! jewel p9 is indicat$ by ! dott$ circle a1 & ! jewel p9 ( ! usual cyl9drical =m1 ) two-fif?s cut away4 ,! safety roll] is ?ree-fif?s ( ! diamet] ( ! pit* diamet] ( ! jewel-p9 action1 z indicat$ by ! dott$ circle a4 ,! safety roll] is %[n 9 full outl9e at ,b'1 & ! pass+ holl[ at ,e4 ,x w be se5 t ! arc ( int]section embrac$ betwe5 ! radial l9es ,b c & ,b d is ab\t sixty-"o & a half degrees = ! roll]1 b ! angul> ext5t ( ! pass+ holl[ is only a little ov] ?irty-two degrees4 ,! pass+ holl[ ,e is locat$ & def9$ by draw+ ! radial l9e ,b c f ! c5t] ,b ?r\gh ! int]section ( radial l9e ,a i ) ! dott$ arc b1 :i* repres5ts ! pit* circle ( ! safety roll]4 ,we w "n ?is int]section ! po9t l4 ,n[ ! end ( ! gu>d po9t ,c t]m9ates at ! po9t l1 & ! pass+ holl[ ,e ext5ds on b sixte5 degrees on ea* side ( ! radial l9e ,b c4 ,illu/ration3 ,fig4 #hb ,! roll] action is suppos$ to cont9ue ?r\gh ?irty degrees ( angul> motion ( ! balance /aff1 & is embrac$ on ! circle a betwe5 ! radial l9e ,b k & ,b o4 ,to del9eate ! inn] face ( ! horn p ( ! =k ,f we draw ! %ort arc g1 f ,a z a c5t]1 & on said arc locate at two degrees f ! c5t] at ,b ! po9t f4 ,we w designate ! upp] angle ( ! out] face ( ! jewel p9 ,d z ! po9t s &1 f ,a z a c5t]1 sweep ?r\gh ?is po9t s ! %ort arc n n4 ,p>allel ) ! l9e ,a i & at ! di/ance ( half ! diamet] ( ! jewel p9 ,d1 we draw ! %ort l9es t t'1 :i* def9e ! inn] faces ( ! =k4 ,! int]section ( ! %ort l9e t ) ! arc n we w designate ! po9t r4 ,) our divid]s set to embrace ! space betwe5 ! po9t r & ! po9t f1 we sweep ! arc :i* def9es ! inn] face ( ! prong ( ! =k4 ,! space we j made use ( is practically ! same z ! radius ( ! circle a1 & consequ5tly ( ! same curvature4 ,practically1 ! l5g? ( ! gu>d po9t ,c' is made z long z w1 ) c]ta9ty1 cle> ! safety roll] ,b 9 all positions4 ,:ile we set ! po9t f at two degrees f ! c5t] ,b1 /ill1 9 a well-con/ruct$ escapem5t1 "o & a half degrees %\ld be suffici5t1 b ! extra half degree w d no h>m4 ,if ! roll] ,b' is accurately made & ! gu>d po9t ,c' prop]ly fitt$1 ! =k w n h half a degree ( play4 ,! read] w rememb] t 9 ! escapem5t model we describ$ we cut d[n ! drop to "o degree1 be+ less by half a degree ?an advis$ by ,grossmann & ,sauni]4 ,we also advis$ only "o degree ( lock4 ,9 ! p]fect$ lev] escapem5t1 :i* we %all describe & give work+ draw+s = ! con/ruction (1 we %all describe a deta*$ lev] escapem5t ) only eight degrees =k & pallet action1 ) only ?ree-f\r?s ( a degree drop & ?ree-f\r?s ( a degree lock1 :i* we c assure our read]s is easily )9 ! limits ( practical con/ruction by mod]n ma*9]y4 ,,h[ ,,! ,,gu>d ,,po9t ,,is ,,made4 ,illu/ration3 ,fig4 #hc ,! gu>d po9t ,c'1 z %[n at ,fig4 #hb1 is ( extremely simple con/ruction4 ,back ( ! slot ( ! =k1 :i* is ?ree-fif?s ( ! diamet] ( ! jewel p9 9 dep?1 is made a squ>e hole1 z %[n at u1 & ! back end ( ! gu>d po9t ,c is fitt$ to ?is hole s t x is rigid 9 position4 ,?is mann] ( fa/5+ ! gu>d po9t is equally effici5t z t ( atta*+ x ) a screw1 & mu* light]--a matt] ( ! highe/ importance 9 escapem5t con/ruction1 z we h already urg$4 ,ab\t ! be/ mat]ial = su* gu>d po9ts is ei!r alum9um or phosphor bronze1 z su* mat]ial is light] ?an gold & v rigid & /rong4 ,at ,fig4 #hc we %[ a side view ( ! ess5tial p>ts depict$ 9 ,fig4 #hb1 z if se5 9 ! direction ( ! arr[ v1 b we h add$ ! piece :i* holds ! jewel p9 ,d4 ,a c>eful /udy ( ! cut %[n at ,fig4 #hb w soon give ! horological /ud5t an excell5t idea ( ! d\ble-roll] action4 ,we w n[ take up & consid] at l5g? :y ,sauni] draws 8 entrance pallet ) fifte5 degrees draw & 8 exit pallet ) only twelve degrees draw4 ,to make ourselves m conv]sant ) ,sauni]'s me?od ( del9eat+ ! lev] escapem5t1 we reproduce ! ess5tial features ( 8 draw+1 ,fig4 #a1 plate ,,viii1 ( 8 ,mod]n ,horology1 9 :i* he makes ! draw ( ! lock+ face ( ! entrance pallet fifte5 degrees & 8 exit pallet twelve degrees4 ,9 ! cut %[n at ,fig4 #hd we use ! same lett]s ( ref]5ce z he employs4 ,we d n quote 8 description or directions = del9eation because he ref]s to s mu* matt] :i* he has previ\sly giv5 9 ! book j ref]r$ to4 ,besides we _c entirely endorse 8 me?ods ( del9eations = _m reasons1 "o ( :i* appe>s 9 ! draw+ at ,fig4 #hd4 ,illu/ration3 ,fig4 #hd ,,m ,,ab\t ,,tang5tial ,,lock+s4 ,mo/ writ]s endorse ! idea ( tang5tial lock+s1 & ,sauni] speaks ( ! escapem5t z %[n at ,fig4 #hd z hav+ su* tang5tial lock+s1 :i* is n ! case4 ,he def9es ! position ( ! pallet /aff f ! circle t1 :i* repres5ts ! extreme l5g? ( ! tee?2 draw+ ! radial l9es ,a ,d & ,a ,e to embrace an arc ( sixty degrees1 & e/abli%+ ! c5t] ( 8 pallet /aff ,c at ! int]section ( ! l9es ,d ,c & ,e ,c1 :i* are drawn at "r angles to ! radial l9es ,a ,d & ,a ,e1 & tang5tial to ! circle t4 ,"h is an error2 ! l9es def9+ ! c5t] ( ! pallet /aff %\ld h be5 drawn tang5t to ! circle s1 :i* repres5ts ! lock+ angle ( ! tee?4 ,?is w\ld h plac$ ! c5t] ( ! pallet /aff f>!r 91 or clos] to ! :eel4 ,any p]son c see at a glance t ! pallets z del9eat$ are n tang5tial 9 a true s5se4 ,illu/ration3 ,fig4 #he ,we h previ\sly consid]$ engag+ friction & also repeat$ly h spok5 ( tang5tial lock+s1 b w repeat ! idea ( tang5tial lock+s at ,fig4 #he4 ,a tang5tial lock+ is neutral1 or ne>ly s1 z reg>ds engag+ friction4 ,= illu/ration we ref] to ,fig4 #he1 :]e ,a repres5ts ! c5t] ( an escape :eel4 ,we draw ! radial l9es ,a y & ,a z s t !y embrace sixty degrees ( ! arcs s or t1 :i* correspond to simil> circles 9 ,fig4 #hd1 & repres5t ! extreme ext5t ( ! tee? & likewise ! lock+ angle ( su* tee?4 ,9 fact1 ) ! club-too? escapem5t all t "p ( a too? :i* ext5ds beyond ! l9e s %\ld be consid]$ ! same z ! add5dum 9 ge> :eels4 ,consequ5tly1 a tang5tial lock+ made to co9cide ) ! c5t] ( ! impulse plane1 z recomm5d$ by ,sauni]1 w\ld require ! pallet /aff to be locat$ at ,c' in/ead ( ,c1 z he draws x4 ,if ! angle k' ( ! too? k 9 ,fig4 #hd 0 ext5d$ outw>d f ! c5t] ,a s x w\ld engage or re/ on ! lock+ face ( ! entrance pallet z %[n at ,fig4 #hd1 !n ! draw ( ! lock+ angle w\ld n be q fifte5 degrees2 b x is evid5t no lock c take place until ! angle a ( ! entrance pallet has pass$ inside ! circle s4 ,we w\ld say "h t we h add$ ! lett]s s & t to ! orig9al draw+s1 z we h frequ5tly to ref] to ^! circles1 & )\t lett]s _h no means ( designation4 ,be=e ! lock+ angle k' ( ! too? c engage ! pallet1 z %[n 9 ,fig4 #hd1 ! pallet mu/ turn on ! c5t] ,c ?r\gh an angul> movem5t ( at lea/ f\r degrees4 ,we %[ ! situation 9 ! diagram at ,fig4 #hf1 us+ ! same lett]s ( ref]5ce = simil> p>ts z 9 ,fig4 #hd4 ,illu/ration3 ,fig4 #hf ,z drawn 9 ,fig4 #hd ! angle ( draft ,g a ,i is equal to fifte5 degrees1 b :5 br\ght 9 a position to act z %[n at ,g a' ,i'1 ,fig4 #hf1 ! draw is less ev5 ?an twelve degrees4 ,! angle ,c a ,i rema9s con/ant1 z %[n at ,c a' ,i'1 b ! relation to ! radial ,a ,g *anges :5 ! pallet moves ?r\gh ! angle w ,c w'1 z x mu/ :5 lock$4 ,a tang5tial lock+ 9 ! true s5se ( ! mean+ ( ! phrase is a lock+ set s t a pallet ) its face co9cid+ ) a radial l9e l ,a ,g w\ld be neutral1 & ! ?ru/ ( ! too? w\ld be tang5t to ! circle describ$ by ! lock+ angle ( ! too?4 ,?us ! c5t] ,c1 ,fig4 #hf1 is plac$ on ! l9e w' :i* is tang5t to ! circle s2 said l9e w' also be+ at "r angles to ! radial l9e ,a ,g4 ,! facts are1 ! problems relat+ to ! club-too? lev] escapem5t are v intricate & require v c>eful analysis1 & )\t su* c>e ! horological /ud5t c v readily be misl$4 ,faulty draw+s1 :5 /udy+ su* problems1 lead to no end ( errors1 & practical m5 :o make imp]fect draw+s lead to ! popul> phrase1 ,oh1 su* a matt] may be all "r 9 !ory1 b w n "w 9 practice4 ,we %\ld always be> 9 m9d t !ory1 if "r1 mu/ lead practice4 ,,correct ,,draw+ ,,requir$4 ,if we del9eate our entrance pallet to h a draw ( twelve degrees :5 9 actual contact ) ! too?1 & !n con/ruct 9 exact con=mity ) su* draw+s1 we w f9d our lev] to hug ! banks 9 e in/ance4 ,x is inatt5tion to su* details :i* produces ! errors ( mak]s compla9$ ( by ,sauni] 9 section #fif ( 8 ,mod]n ,horology1 & :i* he attempts to correct by draw+ ! lock+ face at fifte5 degrees draw4 ,we %all %[ t nei!r ,c nor ,c'1 ,fig4 #he1 is ! !oretically correct position = ! pallet c5t] = a tang5tial lock+4 ,we w n[ take up ! consid]ation ( a club-too? lev] escapem5t ) circul> pallets & tang5tial lock+s2 b previ\s to mak+ ! draw+s we mu/ decide sev]al po9ts1 among :i* are ! ?ickness ( ! pallet arms1 :i* e/abli%es ! angul> motion ( ! escape :eel utiliz$ by su* pallet arms1 & also ! angul> motion imp>t$ to ! pallets by ! impulse faces ( ! tee?4 ,we w1 = ! pres5t1 accept ! ?ickness ( ! arms z be+ equival5t to five degrees ( angul> ext5t ( ! pit* circle ( ! escape :eel4 ,illu/ration3 ,fig4 #hg ,illu/ration3 ,fig4 #hh ,9 mak+ our draw+s we comm5ce1 z on =m] occasions1 by e/abli%+ ! c5t] ( our escape :eel at ,a1 ,fig4 #hg1 & sweep+ ! arc a a to repres5t ! pit* circle ( su* :eel4 ,?r\gh ! c5t] ,a we draw ! v]tical l9e ,a ,b1 :i* is suppos$ to also pass ?r\gh ! c5t] ( ! pallet /aff4 ,! int]section ( ! l9e ,a ,b ) ! arc a we t]m ! po9t d1 & f ?is po9t we lay (f on said arc a ?irty degrees ea* side ( said int]section1 & ?us e/abli% ! po9ts c b4 ,f ,a1 ?r\gh ! po9t c1 we draw ! l9e ,a c c'4 ,on ! arc a a & two & a half degrees to ! left ( ! po9t c we e/abli% ! po9t f1 :i* space repres5ts half ( ! ?ickness ( ! entrance pallet4 ,f ,a we draw ?r\gh ! po9t f ! l9e ,a f f'4 ,f f1 & at "r angles to said l9e ,a f1 we draw ! l9e f e until x crosses ! l9e ,a ,b4 ,n[ ?is l9e f e is tang5t to ! arc a f ! po9t f1 & consequ5tly a lock+ plac$ at ! po9t f is a true tang5tial lock+2 & if ! re/+ or lock+ face ( a pallet 0 made to co9cide ) ! l9e ,a f'1 su* lock+ face w\ld be /rictly dead or neutral4 ,! int]section ( ! l9e f e ) ! l9e ,a ,b we call ! po9t ,c1 & locate at ?is po9t ! c5t] ( our pallet /aff4 ,accord+ to ! me?od ( del9eat+ ! lev] escapem5t by ,moritz ,grossmann ! tang5t l9e = locat+ ! c5t] ( ! pallet /aff is drawn f ! po9t c1 :i* w\ld locate ! c5t] ( ! pallet /aff at ! po9t h on ! l9e ,a ,b4 ,grossmann1 9 del9eat+ 8 lock+ face = ! draw1 %[s su* face at an angle ( twelve degrees to ! radial l9e ,a f'1 :5 he %\ld h drawn x twelve degrees to an imag9>y l9e %[n at f i1 :i* is at "r angles to ! l9e f h4 ,to ! writ]'s m9d ?is is n j z x %\ld be1 & may lead to misund]/&+ & bad con/ruction4 ,we %\ld always be> 9 m9d ! fact t ! basis ( a lock+ face is a neutral plane plac$ at "r angles to ! l9e ( ?ru/1 & ! draw comes f a lock+ face plac$ at an angle to su* neutral plane4 ,a c>eful /udy ( ! diagram at ,fig4 #hh w give ! read] correct ideas4 ,if a too? locks at ! po9t c1 ! tang5tial ?ru/ w\ld be on ! l9e c h'1 & a neutral lock+ face w\ld be on ! l9e ,a c4 ,,neutral ,,lock+s4 ,to aid 9 explanation1 let u remove ! pallet c5t] to ,d2 !n ! l9e ( ?ru/ w\ld be c ,d & a neutral lock+ face w\ld co9cide ) ! l9e m m1 :i* is at "r angles to ! l9e c ,d4 ,if we %\ld n[ make a lock+ face ) a draw & at an angle to ! l9e c ,d1 say1 = illu/ration1 to correspond to ! l9e c c' 7leav+ ! pallet c5t] at ,d71 we w\ld h a /rong draw & also a cruel engag+ friction4 ,if1 h[ev]1 we remov$ ! engag+ too?1 :i* we h j conceiv$ to be at c1 to ! po9t k on ! arc a' a'1 ,fig4 #hh1 ! pallet c5t] ,d w\ld !n repres5t a tang5tial lock+1 & a neutral pallet face w\ld co9cide ) ! radial l9e ,a k'2 & a lock+ face ) twelve degrees draw w\ld co9cide ne>ly ) ! l9e l4 ,let u next analyze :at ! effect w\ld be if we *ang$ ! pallet c5t] to h'1 ,fig4 #hh1 leav+ ! engag+ too? /ill at k4 ,9 ?is in/ance ! l9e l l w\ld !n co9cide ) a neutral lock+ face1 & to obta9 ! prop] draw we %\ld del9eate ! lock+ face to correspond to ! l9e k n1 :i* we assume to be twelve degrees f k l4 ,x is n to be und]/ood t we insi/ on precisely twelve degrees draw f a neutral plane = lock+ faces = lev] pallets4 ,:at we d insi/ ^u1 h[ev]1 is a safe & sure draw = a lev] pallet :i* w hold a =k to ! banks & w also return x to su* banks if by accid5t ! =k is mov$ away4 ,we are well aw>e t x takes lots ( pati5t1 h>d /udy to ma/] ! complications ( ! club-too? lev] escapem5t1 b x is e wat*mak]'s duty to conqu] ! problem4 ,! def9ition ( lock1 9 ! deta*$ lev] escapem5t1 is ! /oppage or arre/ ( ! escape :eel ( a wat* :ile ! balance is left free or deta*$ to p]=m ! great] portion ( its arc ( vibration4 ,draw is a function ( ! lock+ p>ts to pres]ve ! =k 9 ! prop] position to receive & act on ! jewel p9 ( ! balance4 ,x %\ld be borne 9 m9d 9 connection ) lock & draw1 t ! l9e ( ?ru/ z project$ f ! lock$ too? ( ! escape :eel %\ld be z ne> tang5tial z practicable4 ,?is maxim applies p>ticul>ly to ! entrance pallet4 ,we w\ld beg to add t practically x w make b little odds :e!r we plant ! c5t] ( our pallet /aff at ,c or h1 ,fig4 #hg1 provid$ we modify ! lock+ & impulse angles ( our pallets to con=m to su* pallet c5t]4 ,b x w n d to arrange ! p>ts = "o c5t] & !n *ange to ano!r4 ,,practical ,,h9ts ,,= ,,lev] ,,escapem5ts4 ,app>5tly !re seems to be a belief ) v _m wat*mak]s t !re is a set ( %or?& rules = sett+ an escapem5t1 especially 9 ,am]ican wat*es1 :i*1 if once acquir$1 conqu]s all imp]fections4 ,n[ we wi% to disabuse ! m9ds ( our read]s ( any su* notions4 ,al?\gh ! lev] escapem5t1 z adopt$ by our ,am]ican factories1 is con/ruct$ on c]ta9 l9es1 /ill ^! l9es are subject to modifications1 su* z may be dem&$ = c]ta9 defects ( con/ruction4 ,if we c\ld duplicate e "p ( a wat* movem5t p]fectly1 !n we c\ld h c]ta9 rules to g by1 & fix$ templets c\ld be us$ = sett+ pallet /ones & correct+ o!r escapem5t faults4 ,let u n[ make an analysis ( ! action ( a lev] escapem5t4 ,we %[ at ,fig4 #hi an ord9>y eighte5-size full-plate lev] ) =k & pallets4 ,! dott$ l9es a b are suppos$ to repres5t an angul> movem5t ( t5 degrees4 ,n[1 x is ! function ( ! =k to c>ry ! p[] ( ! tra9 to ! balance4 ,h[ well ! =k p]=ms its (fice we w consid] subsequ5tly2 = ! pres5t we are deal+ ) ! p[] z convey$ to ! =k by ! pallets z %[n at ,fig4 #hi4 ,illu/ration3 ,fig4 #hi ,! angul> motion betwe5 ! l9es a c 7:i* repres5ts ! lock7 is n only absolutely lo/--wa/$--b dur+ ?is movem5t ! tra9 has to retrograde2 t is1 ! dynamic =ce /or$ 9 ! mom5tum ( ! balance has to actually turn ! tra9 backw>d & aga9/ ! =ce ( ! ma9spr+4 ,true1 x is only ?r\gh a v %ort arc1 b ! necess>y =ce to effect ?is has to be disc\nt$ f ! p[] /or$ 9 ! balance f a =m] impulse4 ,= ?is reason we %\ld make ! angul> motion ( unlock+ z brief z possible4 ,grossmann1 9 8 essay1 endorses "o & a half degrees z ! prop] lock4 ,9 ! description :i* we employ$ 9 describ+ ! l>ge model = illu/rat+ ! action ( ! deta*$ lev] escapem5t1 we cut ! lock to "o degree1 & 9 ! description ( ! up-to-date lev] escapem5t1 :i* we %all h]eaft] give1 we %all cut ! lock d[n to ?ree-qu>t]s ( a degree1 a p]fection easily to be atta9$ by mod]n tools & appliances4 ,we %all also cut ! drop d[n to ?ree-qu>t]s ( a degree4 ,by ^! two economies we m ?an make up = ! p[] lo/ 9 unlock+4 ,) highly poli%$ ruby or sapphire pallets t5 degrees ( draw is ample4 ,b su* draw mu/ positively be t5 degrees f a neutral lock+ face1 n an escapem5t drawn on pap] & call$ t5 degrees1 b :5 actually measur$ w\ld only %[ eight & a half or n9e degrees4 ,,! ,,p]fect$ ,,lev] ,,escapem5t4 ,) t5 degrees angul> motion ( ! lev] & "o & a half degrees lock1 we %\ld h eight & a half degrees impulse4 ,! pi? ( ! problem1 z reg>ds pallet action1 = ! practical workman c be embodi$ 9 ! foll[+ "q3 ,:at proportion ( ! p[] d]iv$ f ! twelve degrees ( angul> motion ( ! escape :eel is really convey$ to ! =k8 ,! great leak ( p[] z transmitt$ by ! lev] escapem5t to ! balance is to be f\nd 9 ! pallet action1 & we %all devote special att5tion to f9d+ & /opp+ su* leaks4 ,,:5 ,,p[] ,,is ,,lo/ ,,9 ,,! ,,lev] ,,escapem5t4 ,if we use a rat*et-too? escape :eel we mu/ all[ at lea/ "o & a half degrees drop to free ! back ( ! too?2 b ) a club-too? escape :eel made z c be con/ruct$ by prop] skill & c>e1 ! drop c be cut d[n to ?ree-qu>t]s ( a degree1 or "o-half ( ! loss ) ! rat*et too?4 ,we d n wi% our read]s to imag9e t su* a condition exi/s 9 mo/ ( ! s-call$ f9e wat*es1 because if we take ! tr\ble to measure ! actual drop ) "o ( ! little in/rum5ts we h describ$1 x w be f\nd t ! drop is seldom less ?an two1 or ev5 ?ree degrees4 ,if we measure ! angul> movem5t ( ! =k :ile lock$1 x w seldom be f\nd less ?an two or ?ree degrees4 ,n[1 we c all und]/& t ! friction ( ! lock+ surface has to be c\nt$ z well z ! recoil ( ! draw4 ,lock+ friction is seldom look$ aft] z c>efully z ! situation dem&s4 ,our factories make ! impulse face ( ! pallets r\nd$1 b leave ! lock+ face flat4 ,we are aw>e ?is condition is1 9 a degree1 necess>y f ! use ( expos$ pallets4 ,9 _m ( ! ,engli% lev] wat*es ) rat*et tee?1 ! lock+ faces are made cyl9drical1 b ) su* wat*es ! pallet /ones1 z f> z ! writ] has se51 are set close2 t is1 ) /eel pallet arms ext5d+ above & bel[ ! /one4 ,!re is ano!r feature ( ! club-too? lev] escapem5t t next dem&s our att5tion :i* we h nev] se5 discuss$4 ,we ref] to arrang+ & dispos+ ( ! impulse ( ! escape :eel to meet ! resi/ance ( ! hairspr+4 ,let u imag9e ! dott$ l9e ,a d1 ,fig4 #hi1 to repres5t ! c5t] ( action ( ! =k4 ,we c readily see t ! =k 9 a /ate ( re/ w\ld /& half way betwe5 ! two banks f ! action ( ! hairspr+1 & 9 ! pallet action ! =ce ( ! escape :eel1 "o too? ( :i* re/s on ! impulse face ( a pallet1 w\ld be ex]t$ aga9/ ! ela/ic =ce ( ! hairspr+4 ,if ! =ce ( ! ma9spr+1 z repres5t$ by ! escape-:eel too?1 is sup]ior to ! p[] ( ! hairspr+1 ! wat* />ts itself4 ,! phases ( ?is important "p ( ! deta*$ lev] escapem5t w be fully discuss$4 ,,ab\t ,,! ,,club-,,too? ,,escapem5t4 ,we w n[ take up a /udy ( ! deta*$ lev] escapem5t z relates to pallet action1 ) ! po9t specially 9 view ( con/ruct+ an escapem5t :i* _c set 9 ! pocket1 or1 9 o!r words1 an escapem5t :i* w />t aft] w9d+ 7if run d[n7 )\t %ak+ or any =ce o!r ?an t suppli$ by ! tra9 z impell$ by ! ma9spr+4 ,9 ! draw+ at ,fig4 #ij we propose to utilize elev5 degrees ( escape-:eel action1 aga9/ t5 & a half1 z laid d[n by ,grossmann4 ,( ?is elev5 degrees we propose to divide ! impulse arc ( ! escape :eel 9 six & five degrees1 six to be d]iv$ f ! impulse face ( ! club too? & five f ! impulse plane ( ! pallet4 ,! pallet action we divide into five & f\r1 ) "o degree ( lock4 ,five degrees ( pallet action is d]iv$ f ! impulse face ( ! too? & f\r f ! impulse face ( ! pallet4 ,! read] w please be> 9 m9d t we d n give ^! proportions z imp]ative1 because we propose to give ! fulle/ evid5ce into ! read]'s h&s & enable him to judge = himself1 z we d n believe 9 lay+ d[n imp]i\s laws t ! read] mu/ accept on our ass]tion z be+ correct4 ,our idea is r to furni% ! prop] facts & put him 9 a situation to "k = himself4 ,! read] is urg$ to make ! draw+s = himself on a l>ge scale1 say1 an escape :eel #aj pit* diamet]4 ,su* draw+s w enable him to realize small errors :i* h be5 tol]at$ too mu* 9 draw+s ( ?is k9d4 ,! draw+s1 z !y appe> 9 ! cut1 are "o-f\r? ! size recomm5d$1 & _m ( ! l9es fail to %[ po9ts we desire to call att5tion to4 ,z = in/ance1 ! pallet c5t] at ,b is tang5tial to ! pit* circle a f ! po9t ( too? contact at f4 ,to e/abli% ?is po9t we draw ! radial l9es ,a c & ,a d f ! escape-:eel c5t] ,a1 z %[n1 by lay+ (f ?irty degrees on ea* side ( ! int]section ( ! v]tical l9e i 7pass+ ?r\gh ! c5t]s ,a ,b7 ) ! arc a1 & !n lay+ (f two & a half degrees on a & e/abli%+ ! po9t f1 & ?r\gh f f ! c5t] ,a draw ! radial l9e ,a f'4 ,?r\gh ! po9t f we draw ! tang5t l9e b' b b''1 & at ! int]section ( ! l9e b ) i we e/abli% ! c5t] ( our pallet /aff at ,b4 ,at two & a half degrees f ! po9t c we lay (f two & a half degrees to ! "r ( said po9t & e/abli% ! po9t n1 & draw ! radial l9e ,a n n'1 :i* e/abli%es ! ext5t ( ! arc ( angul> motion ( ! escape :eel utiliz$ by ! pallet arm4 ,illu/ration3 ,fig4 #ij ,we h n[ come to ! po9t :]e we mu/ ex]cise our reason+ p[]s a little4 ,we "k ! lock+ angle ( ! escape-:eel too? passes on ! arc a1 & if we utilize ! impulse face ( ! too? = five degrees ( pallet or lev] motion we mu/ %ape x to ?is end4 ,we draw ! %ort arc k ?r\gh ! po9t n1 kn[+ t ! inn] angle ( ! pallet /one mu/ re/ on ?is arc :]ev] x is situat$4 ,z1 = in/ance1 :5 ! lock+ face ( ! pallet is engag$1 ! inn] angle ( ! pallet /one mu/ re/ some:]e on ?is arc 7k7 inside ( a1 & ! extreme out] angle ( ! impulse face ( ! too? mu/ "p ) ! pallet on ?is arc k4 ,,h[ ,,to ,,locate ,,! ,,pallet ,,action4 ,) ! p>ts relat$ to ea* o!r z %[n 9 ! cut1 to e/abli% :]e ! inn] angle ( ! pallet /one is locat$ 9 ! draw+1 we measure d[n on ! arc k five degrees f its int]section ) a1 & e/abli% ! po9t s4 ,! l9e ,b b1 ,fig4 #ij1 z ! read] w see1 does n co9cide ) ! int]section ( ! arcs a & k1 & to conv5i5tly get at ! prop] location = ! inn] angle ( our pallet /one1 we draw ! l9e ,b b'1 :i* passes ?r\gh ! po9t n locat$ at ! int]section ( ! arc a ) ! arc k4 ,f ,b z a c5t] we sweep ! %ort arc j ) any conv5i5t radius ( :i* we h a sixty-degree scale1 & f ! int]section ( ,b b' ) j we lay (f five degrees & draw ! l9e ,b s'1 :i* e/abli%es ! po9t s on ! arc k4 ,z /at$ above1 we all[ "o degree = lock1 :i* we e/abli% on ! arc o by lay+ (f "o degree on ! arc j bel[ its int]section ) ! l9e ,b b4 ,we d n %[ ?is l9e 9 ! draw+1 f ! fact t x comes s ne> to ,b b' t x w\ld confuse ! read]4 ,above ! arc a on ! arc k at five degrees f ! po9t n we e/abli% ! po9t l1 by lay+ (f five degrees on ! arc j above ! int]section ( ! l9e ,b b ) j4 ,! po9t l1 ,fig4 #ij1 e/abli%es :]e ! out] angle ( ! too? w pass ! arc k to give five degrees ( angul> motion to ! lev]4 ,f ,a z a c5t] we sweep ! arc m1 pass+ ?r\gh ! po9t l4 ,! int]section ( ! arc m ) ! l9e ,a h we call ! po9t r1 & by draw+ ! "r l9e r f we del9eate ! impulse face ( ! too?4 ,on ! arc o & "o degree bel[ its int]section ) ! l9e ,b b we e/abli% ! po9t t1 & by draw+ a "r l9e f t to s we del9eate ! impulse face ( our entrance pallet4 ,,action ,,draw+s4 ,"o great fault ) mo/ ( our text books on horology lies 9 ! fact t :5 deal+ ) ! deta*$ lev] escapem5t ! draw+s %[ only ! position ( ! pallets :5 lock$1 & _m ( ! conditions assum$ are arriv$ at by m5tal processes1 )\t mak+ ! prop] draw+s to %[ ! actual relation ( ! p>ts at ! "t su* conditions exi/4 ,= illu/ration1 x is (t5 urg$ t !re is a "t 9 ! action ( ! club-too? lev] escapem5t action :5 ! incl9e on ! too? & ! incl9e on ! pallet pres5t p>allel surfaces1 & consequ5tly endure excessive friction1 especially if ! oil is a little ?ick5$4 ,we propose to make draw+s to %[ ! exact position & relation ( ! entrance pallet & too? at ?ree int]vals viz3 7#a7 ,lock$2 7#b7 ! position ( ! p>ts :5 ! lev] has p]=m$ "o-half ( its angul> motion2 7#c7 :5 half ( ! impulse face ( ! too? has pass$ ! pallet4 ,! position ( ! entrance pallet :5 lock$ is suffici5tly well %[n 9 ,fig4 #ij to give a correct idea ( ! relations ) ! entrance pallet2 & to con=m to /atem5t 7#b71 z above4 ,we w n[ del9eate ! entrance pallet1 n 9 actual contact1 h[ev]1 ) ! pallet1 because if we did s ! l9es we employ$ w\ld become confus$4 ,! me?ods we use are su* t we c del9eate ) absolute correctness ei!r a pallet or too? at any po9t 9 its angul> motion4 ,we h previ\sly giv5 in/ructions = draw+ ! pallet lock$2 & to del9eate ! pallet aft] five degrees ( angul> motion1 we h only to conceive t we sub/itute ! l9e s' = ! l9e b'4 ,all angul> motions & measurem5ts = pallet actions are f ! c5t] ( ! pallet /aff at ,b4 ,z we desire to n[ del9eate ! entrance pallet1 x has pass$ ?r\gh five degrees ( angul> motion & ! inn] angle s n[ lies on ! pit* circle ( ! escape :eel1 ! angul> space betwe5 ! l9es b' s' be+ five degrees1 ! l9e b'' r$uc+ ! impulse face to f\r degrees4 ,,draw+ ,,an ,,escapem5t ,,to ,,%[ ,,angul> ,,motion4 ,to del9eate our lock+ face we draw a l9e at "r angles to ! l9e ,b b'' f ! po9t t1 said po9t be+ locat$ at ! int]section ( ! arc o ) ! l9e ,b b''4 ,to draw a l9e p]p5dicul> to ,b b'' f ! po9t t1 we take a conv5i5t space 9 our divid]s & e/abli% on ! l9e ,b b'' ! po9ts x x' at equal di/ances f ! po9t t4 ,we op5 ! divid]s a little 7no special di/ance7 & sweep ! %ort arcs x'' x'''1 z %[n at ,fig4 #ia4 ,?r\gh ! int]section ( ! %ort arcs x'' x''' & to ! po9t t we draw ! l9e t y4 ,! read] w see f our =m] explanations t ! l9e t y repres5ts ! neutral plane ( ! lock+ face1 & t to h ! prop] draw we mu/ del9eate ! lock+ face ( our pallet at twelve degrees4 ,to d ?is we draw ! l9e t x' at twelve degrees to ! l9e t y1 & proce$ to outl9e our pallet faces z %[n4 ,we c n[ und]/&1 aft] a mom5t's ?\ght1 t we c del9eate ! impulse face ( a too? at any po9t or place we *oose by lay+ (f six degrees on ! arc m1 & draw+ radial l9es f ,a to embrace su* arc4 ,to illu/rate1 suppose we draw ! radial l9es w' w'' to embrace six degrees on ! arc a4 ,we make ^! l9es contigu\s to ! entrance pallet ,c = conv5i5ce only4 ,to del9eate ! impulse face ( ! too?1 we draw a l9e ext5d+ f ! int]section ( ! radial l9e ,a' w' ) ! arc m to ! int]section ( ! arc a ) ! radial l9e ,a w''4 ,illu/ration3 ,fig4 #ia ,we next desire to "k :]e contact w take place betwe5 ! :eel-too? ,d & pallet ,c4 ,to det]m9e ?is we sweep1 ) our divid]s set s "o leg re/s at ! escape-:eel c5t] ,a & ! o!r at ! out] angle t ( ! entrance pallet1 ! %ort arc t' w4 ,:]e ?is arc int]sects ! l9e w 7:i* repres5ts ! impulse face ( ! too?7 is :]e ! out] angle t ( ! entrance pallet ,c w t\* ! impulse face ( ! too?4 ,to prove ?is we draw ! radial l9e ,a v ?r\gh ! po9t :]e ! %ort arc t t' passes ?r\gh ! impulse face w ( ! too? ,d4 ,!n we cont9ue ! l9e w to n1 to repres5t ! impulse face ( ! too?1 & !n measure ! angle ,a w n betwe5 ! l9es w n & v ,a1 & f9d x to be approximately sixty-f\r degrees4 ,we !n1 by a simil> process1 measure ! angle ,a t s' & f9d x to be approximately sixty-six degrees4 ,:5 contact ensues betwe5 ! too? ,d & pallet ,c ! too? ,d w attack ! pallet at ! po9t :]e ! radial l9e ,a v crosses ! too? face4 ,we h n[ expla9$ h[ we c del9eate a too? or pallet at any po9t ( its angul> motion1 & w next expla9 h[ to apply ?is k 9 actual practice4 ,,practical ,,problems ,,9 ,,! ,,lev] ,,escapem5t4 ,to del9eate our entrance pallet aft] "o-half ( ! engag$ too? has pass$ ! inn] angle ( ! entrance pallet1 we proce$1 z 9 =m] illu/rations1 to e/abli% ! escape-:eel c5t] at ,a1 & f x sweep ! arc b1 to repres5t ! pit* circle4 ,we next sweep ! %ort arcs p s1 to repres5t ! arcs ?r\gh :i* ! inn] & out] angles ( ! entrance pallet move4 ,n[1 to comply ) our /atem5t z above1 we mu/ draw ! too? z if half ( x has pass$ ! arc s4 ,to d ?is we draw f ,a z a c5t] ! radial l9e ,a j1 pass+ ?r\gh ! po9t s1 said po9t s be+ locat$ at ! int]section ( ! arcs s & b4 ,! too? ,d is to be %[n z if "o half ( x has pass$ ! po9t s2 &1 consequ5tly1 if we lay (f ?ree degrees on ea* side ( ! po9t s & e/abli% ! po9ts d m1 we h locat$ on ! arc b ! angul> ext5t ( ! too? to be drawn4 ,to aid 9 our del9eations we draw f ! c5t] ,a ! radial l9es ,a d' & ,a m'1 pass+ ?r\gh ! po9ts d m4 ,! arc a is next drawn z 9 =m] in/ructions & e/abli%es ! l5g? ( ! add5dum ( ! escape-:eel tee?1 ! out] angle ( our escape-:eel too? be+ locat$ at ! int]section ( ! arc a ) ! radial l9e ,a d'4 ,z %[n 9 ,fig4 #ib1 ! impulse planes ( ! too? ,d & pallet ,c are 9 contact &1 consequ5tly1 9 p>allel planes1 z m5tion$ on page #ia4 ,x is n an easy matt] to det]m9e at exactly :at degree ( angul> motion ( ! escape :eel su* condition takes place2 because to det]m9e su* relation ma!matically requires a k ( high] ma!matics1 :i* w\ld require m /udy ?an mo/ practical m5 w\ld c>e to be/[1 especially z !y w\ld h b v little use = su* k except = ?is problem & a few o!rs 9 deal+ ) epicycloidal curves = ! tee? ( :eels4 ,= all practical purposes x w make no diff]5ce :e!r su* p>allelism takes place aft] eight or n9e degrees ( angul> motion ( ! escape :eel subsequ5t to ! lock+ action4 ,! great po9t1 z f> z practical results g1 is to det]m9e if x takes place at or ne> ! "t ! escape :eel meets ! greate/ resi/ance f ! hairspr+4 ,we f9d by analysis ( our draw+ t p>allelism takes place ab\t ! "t :5 ! too? has ?ree degrees ( angul> motion to make1 & ! pallet lacks ab\t two degrees ( angul> movem5t = ! too? to escape4 ,x is ?us evid5t t ! relations1 z %[n 9 our draw+1 are 9 favor ( ! tra9 or ma9spr+ p[] ov] hairspr+ resi/ance z ?ree is to two1 :ile ! av]age is only z elev5 to t52 t is1 ! escape :eel 9 its entire ef=t passes ?r\gh elev5 degrees ( angul> motion1 :ile ! pallets & =k move ?r\gh t5 degrees4 ,! /ud5t w ?us see we h arrang$ to give ! tra9-p[] an advantage :]e x is mo/ ne$$ to ov]come ! oppos+ influ5ce ( ! hairspr+4 ,illu/ration3 ,fig4 #ib ,z reg>ds ! exalt$ adhesion ( ! p>allel surfaces1 we fancy !re is m h>m fe>$ ?an really exi/s1 because1 to take ! wor/ view ( ! situation1 su* p>allelism only exi/s = ! briefe/ duration1 9 a practical s5se1 because !oretically ^! surfaces nev] slide on ea* o!r z p>allel planes4 ,ma!matically consid]$1 ! !oretical plane repres5t$ by ! impulse face ( ! too? approa*es p>allelism ) ! plane repres5t$ by ! impulse face ( ! pallet1 arrives at p>allelism & in/antly passes away f su* p>allelism4 ,,to ,,draw ,a ,,pallet ,,9 ,,any ,,position4 ,z del9eat$ 9 ,fig4 #ib1 ! impulse planes ( ! too? & pallet are 9 contact2 b we h x 9 our p[] to del9eate ! pallet at any po9t we *oose betwe5 ! arcs p s4 ,to describe & illu/rate ! above rem>k1 we say ! l9es ,b e & ,b f embrace five degrees ( angul> motion ( ! pallet4 ,n[1 ! impulse plane ( ! pallet occupies f\r ( ^! five degrees4 ,we d n draw a radial l9e f ,b inside ( ! l9e ,b e to %[ :]e ! out] angle ( ! impulse plane comm5ces1 b ! read] w see t ! impulse plane is drawn "o degree on ! arc p bel[ ! l9e ,b e4 ,we cont9ue ! l9e h h to repres5t ! impulse face ( ! too?1 & measure ! angle ,b n h & f9d x to be tw5ty-sev5 degrees4 ,n[ suppose we wi% to del9eate ! entrance pallet z if n 9 contact ) ! escape-:eel too?--= illu/ration1 say1 we wi% ! inn] angle ( ! pallet to be at ! po9t v on ! arc s4 ,we draw ! radial l9e ,b l ?r\gh v2 & if we draw ano!r l9e s x passes ?r\gh ! po9t v at an angle ( tw5ty-sev5 degrees to ,b l1 & cont9ue said l9e s x crosses ! arc p1 we del9eate ! impulse face ( our pallet4 ,we measure ! angle i n ,b1 ,fig4 #ib1 & f9d x to be sev5ty-f\r degrees2 we draw ! l9e v t to ! same angle ) v ,b1 & we def9e ! inn] face ( our pallet 9 ! new position4 ,we draw a l9e p>allel ) v t f ! int]section ( ! l9e v y ) ! arc p1 & we def9e our lock+ face4 ,if n[ we revolve ! l9es we h j drawn on ! c5t] ,b until ! l9e l ,b co9cides ) ! l9e f ,b1 we w f9d ! l9e y y to co9cide ) h h1 & ! l9e v v' ) n i4 ,,high] ,,ma!matics ,,appli$ ,,to ,,! ,,lev] ,,escapem5t4 ,we h n[ in/ruct$ ! read] h[ to del9eate ei!r too? or pallet 9 any conceivable position 9 :i* !y c be relat$ to ea* o!r4 ,probably no?+ has af=d$ m effici5t aid to practical me*anics ?an has be5 af=d$ by ! graphic solution ( ab/ruce ma!matical problems2 & if we add to ?is ! means ( correction by ma!matical calculations :i* d n involve ! highe/ ma!matical acquirem5ts1 we h approa*$ pretty close to ! actual requirem5ts ( ! practical wat*mak]4 ,illu/ration3 ,fig4 #ic ,to bett] expla9 :at we mean1 we ref] ! read] to ,fig4 #ic1 :]e we %[ prelim9>y draw+s = del9eat+ a lev] escapem5t4 ,we wi% to asc]ta9 by ! graphic me?od ! di/ance betwe5 ! c5t]s ( action ( ! escape :eel & ! pallet /aff4 ,we make our draw+ v c>efully to a giv5 scale1 z1 = in/ance1 ! radius ( ! arc a is #e4 ,aft] ! draw+ is 9 ! condition %[n at ,fig4 #ic we measure ! di/ance on ! l9e b betwe5 ! po9ts 7c5t]s7 ,a ,b1 & we ?us by graphic means obta9 a measure ( ! di/ance betwe5 ,a ,b4 ,n[1 by ! use ( trigonometry1 we h ! l5g? ( ! l9e ,a f 7radius ( ! arc a7 & all ! angles giv51 to f9d ! l5g? ( f ,b1 or ,a ,b1 or bo? f ,b & ,a ,b4 ,by adopt+ ?is policy we c v]ify ! measurem5ts tak5 f our draw+s4 ,suppose we f9d by ! graphic me?od t ! di/ance betwe5 ! po9ts ,a ,b is #e4gh1 & by trigonometrical computation f9d ! di/ance to be #e4ggfb4 ,we "k f ?is t !re is 4#jjch to be acc\nt$ = some:]e2 b = all practical purposes ei!r measurem5t %\ld be satisfactory1 because our draw+ is ab\t ?irty-eight times ! actual size ( ! escape :eel ( an eighte5-size movem5t4 ,,h[ ,,! ,,basis ,,= ,,close ,,measurem5ts ,,is ,,obta9$4 ,let u fur!r suppose ! diamet] ( our actual escape :eel to be 4#bf1 & we 7 con/ruct+ a wat* aft] ! l9es ( our draw+4 ,by l9es1 9 ?is case1 we mean 9 ! same g5]al =m & ratio ( p>ts2 z1 = illu/ration1 if ! di/ance f ! int]section ( ! arc a ) ! l9e b to ! po9t ,b 0 "o-fifte5? ( ! diamet] ( ! escape :eel1 ?is ratio w\ld hold good 9 ! actual wat*1 t is1 x w\ld be ! "o-fifte5? "p ( 4#bf4 ,aga91 suppose ! diamet] ( ! escape :eel 9 ! l>ge draw+ is #aj & ! di/ance betwe5 ! c5t]s ,a ,b is #e4gh2 to obta9 ! actual di/ance = ! wat* ) ! escape :eel 4#bf diamet]1 we make a /atem5t 9 proportion1 ?us3 #aj 3 #e4gh 33 4#bf to ! actual di/ance betwe5 ! pivot holes ( ! wat*4 ,by computation we f9d ! di/ance to be 4#ae4 ,^! proportions w hold good 9 e "p ( actual con/ruction4 ,all p>ts--?ickness ( ! pallet /ones1 l5g? ( pallet arms1 etc4--be> ! same ratio ( proportion4 ,we measure ! ?ickness ( ! entrance pallet /one on ! l>ge draw+ & f9d x to be 4#dg2 we make a simil> /atem5t to ! "o above1 ?us3 #aj 3 4#dg 33 4#bf to ! actual ?ickness ( ! real pallet /one4 ,by computation we f9d x to be 4#jabb4 ,all angul> relations are alike1 :e!r 9 ! l>ge draw+ or ! small pallets to mat* ! actual escape :eel 4#bf 9 diamet]4 ,?us1 9 ! pallet ,d1 ,fig4 #ic1 ! impulse face1 z reckon$ f ,b z a c5t]1 w\ld occupy f\r degrees4 ,,make ,a ,,l>ge ,,escapem5t ,,model4 ,reason w\ld sugge/ ! idea ( hav+ ! !oretical keep pace & t\* ) ! practical4 ,x has be5 a grave fault ) _m writ]s on horological matt]s t !y did n make & measure ! ab/ractions :i* !y del9eat$ on pap]4 ,we d n mean by ?is to endorse ! cavil we s (t5 he>--,oh1 t is all "r 9 !ory1 b x w n "w 9 practice4 ,if !ory is "r1 practice mu/ con=m to x4 ,! tr\ble ) _m !ories is1 !y d n conta9 all ! elem5ts or factors ( ! problem4 ,illu/ration3 ,fig4 #id ,ne> ! beg9n+ ( ?is treatise we advis$ our read]s to make a l>ge model1 & describ$ 9 detail ! complete p>ts = su* a model4 ,:at we propose n[ is to make adju/able ! pallets & =k to su* a model1 9 ord] t we c set !m bo? "r & wrong1 & ?us practically demon/rate a p]fect action & also ! v>i\s faults to :i* ! lev] escapem5t is subject4 ,! pallet arms are %ap$ z %[n at ,a1 ,fig4 #id4 ,! pallets ,b ,b' c be made ( /eel or /one1 & = all practical purposes ^? made ( /eel answ] q z well1 & h ! advantage ( be+ *eap]4 ,a plate ( %eet brass %\ld be obta9$1 %ap$ z %[n at ,c1 ,fig4 #ie4 ,?is plate is ( ?9 brass1 ab\t ,no4 #ah1 & on x are outl9$ ! pallet arms %[n at ,fig4 #id4 ,illu/ration3 ,fig4 #ie ,illu/ration3 ,fig4 #if ,illu/ration3 ,fig4 #ig ,illu/ration3 ,fig4 #ih ,to make ! pallets adju/able1 !y are set 9 ?ick disks ( %eet brass1 z %[n at ,d1 ,figs4 #ie1 #if & #ig4 ,at ! c5t] ( ! plate ,c is plac$ a brass disk ,e1 ,fig4 #ih1 :i* s]ves to support ! lev] %[n at ,fig4 #ii4 ,?is disk ,e is p]man5tly atta*$ to ! plate ,c4 ,! lev] %[n at ,fig4 #ii is atta*$ to ! disk ,e by two screws1 :i* pass ?r\gh ! holes h h4 ,if we n[ place ! brass pieces ,d ,d' on ! plate ,c 9 su* a way t ! pallets set 9 !m correspond exactly to ! pallets z outl9$ on ! plate ,c1 we w f9d ! action ( ! pallets to be precisely ! same z if ! pallet arms ,a ,a'1 ,fig4 #id1 7 employ$4 ,illu/ration3 ,fig4 #ii ,to enable u to practically exp]im5t ) & to fully demon/rate all ! problems ( lock1 draw1 drop1 etc41 we make q a l>ge hole 9 ,c :]e ! screws b come4 ,to expla91 if ! screws b b 7 tapp$ directly into ,c1 z !y are %[n at ,fig4 #ie1 we c\ld only turn ! disk ,d on ! screw b2 b if we enl>ge ! screw hole 9 ,c to ?ree or f\r times ! natural diamet]1 & !n place ! nut e "u ,c to receive ! screw b1 we c !n set ! disks ,d ,d' & pallets ,b ,b' 9 almo/ any relation we *oose to ! escape :eel1 & clamp ! pallets fa/ & try ! action4 ,we %[ at ,fig4 #ig a view ( ! pallet ,b'1 disk ,d' & plate ,c 7se5 9 ! direction ( ! arr[ c7 z %[n 9 ,fig4 #ie4 ,,practical ,,lessons ,,) ,,=k ,,& ,,pallet ,,action4 ,x w be notic$ 9 ,fig4 #ii t ! hole g = ! pallet /aff 9 ! lev] is oblong2 ?is is to all[ ! lev] to be %ift$ back & =? z relates to roll] & =k action4 ,we w n bo!r ab\t ?is n[1 & only call att5tion to ! capabilities ( su* adju/m5ts :5 requir$4 ,at ! outset we w conceive ! =k ,f atta*$ to ! piece ,e by two screws pass+ ?r\gh ! holes h h1 ,fig4 #ii4 ,su* an arrangem5t w insure ! =k & roll] action keep+ "r if !y are put "r at fir/4 ,fig4 #ajj w d mu* to aid 9 convey+ a cle> impression to ! read]4 ,! idea ( ! adju/able features ( our escapem5t model is to %[ ! effects ( sett+ ! pallets wrong or hav+ !m ( bad =m4 ,= illu/ration1 we make use ( a pallet ) ! angle too acute1 z %[n at ,b'''1 ,fig4 #aja4 ,! problem 9 h& is to f9d out by me*anical exp]im5ts & te/s ! consequ5ces ( su* a *ange4 ,x is evid5t t ! angul> motion ( ! pallet /aff w be increas$1 & t we %all h to op5 "o ( ! bank+ p9s to all[ ! engag+ too? to escape4 ,to trace out all ! consequ5ces ( ?is "o little *ange w\ld require a consid]able am\nt ( /udy1 & _m draw+s w\ld h to be made to illu/rate ! effects :i* w\ld naturally foll[ only "o su* slight *ange4 ,illu/ration3 ,fig4 #ajj ,illu/ration3 ,fig4 #aja ,suppose1 = illu/ration1 we %\ld make su* a *ange 9 ! pallet /one ( ! entrance pallet2 we h increas$ ! angle betwe5 ! l9es k l by 7say7 "o & a half degrees2 by s do+ we w\ld increase ! lock on ! exit pallet to ?ree degrees1 provid$ we 7 work+ on a basis ( "o & a half degrees lock2 & if we pu%$ back ! exit pallet s z to h ! prop] degree ( lock 7"o & a half7 on x1 ! too? :i* w\ld next engage ! entrance pallet w\ld n lock at all1 b w\ld /rike ! pallet on ! impulse in/ead ( on ! lock+ face4 ,aga91 su* a *ange might cause ! jewel p9 to /rike ! horn ( ! =k1 z indicat$ at ! dott$ l9e m1 ,fig4 #ii4 ,deal+ ) su* & simil> ab/ractions by m5tal process requires ! close/ k9d ( reason+2 & if we attempt to del9eate all ! complications :i* foll[ ev5 su* a small *ange1 we w f9d ! job a l5g?y "o4 ,b ) a l>ge model hav+ adju/able p>ts we provide ourselves ) ! means = ! v be/ practical solution1 & ! workman :o makes & manipulates su* a model w soon ma/] ! lev] escapem5t4 ,,quiz ,,problems ,,9 ,,! ,,deta*$ ,,lev] ,,escapem5t4 ,"s ye>s ago a "y wat*mak] fri5d ( ! writ] made1 at 8 sugge/ion1 a model ( ! lev] escapem5t simil> to ! "o describ$1 :i* he us$ to play )1 z he t]m$ x--t is1 he w\ld set ! =k & pallets 7:i* 7 adju/able7 9 all sorts ( ways1 "r ways & wrong ways1 s he c\ld wat* ! results4 ,a favorite pa/ime 0 to set e "p = ! be/ results1 :i* 0 det]m9$ by ! arc ( vibration ( ! balance4 ,by ?is sort ( tra9+ he soon rea*$ t degree ( pr(ici5cy :]e "o c\ld no m puzzle him ) a bad lev] escapem5t ?an y c\ld spoil a meal = him by dis>rang+ 8 knife1 =k & spoon4 ,let u1 z a practical example1 take up ! consid]ation ( a %ort =k4 ,to repres5t ?is 9 our model we take a lev] z %[n at ,fig4 #ii1 ) ! elongat$ slot = ! pallet /aff at g4 ,to facilitate ! description we reproduce at ,fig4 #ajb ! figure j m5tion$1 & also employ ! same lett]s ( ref]5ce4 ,we fancy ev]ybody :o has any k ( ! lev] escapem5t has an idea ( exactly :at a %ort =k is1 & at ! same "t x w\ld p]haps puzzle !m a good deal to expla9 ! diff]5ce betwe5 a %ort =k & a roll] too small4 ,illu/ration3 ,fig4 #ajb ,illu/ration3 ,fig4 #ajc ,9 our practical problems1 z solv$ on a l>ge escapem5t model1 say we fir/ fit our =k ( ! prop] l5g?1 & !n by ! slot g move ! lev] back a little1 leav+ ! bank+s precisely z !y 74 ,:at are ! consequ5ces ( ?is slight *ange8 ,"o ( ! fir/ results :i* w\ld display itself w\ld be discov]$ by ! gu>d p9 fail+ to p]=m its prop] functions4 ,= in/ance1 ! gu>d p9 pu%$ inw>d aga9/ ! roll] w\ld cause ! engag$ too? to pass (f ! lock+ face ( ! pallet1 & ! =k1 in/ead ( return+ aga9/ ! bank+1 w\ld cause ! gu>d p9 to ride ! roll] dur+ ! entire excursion ( ! jewel p94 ,?is fault produces a scrap+ s\nd 9 a wat*4 ,suppose we attempt to rem$y ! fault by b5d+ =w>d ! gu>d p9 b1 z indicat$ by ! dott$ outl9e b' 9 ,fig4 #ajc1 said figure be+ a side view ( ,fig4 #ajb se5 9 ! direction ( ! arr[ a4 ,?is policy w\ld prev5t ! engag$ pallet f pass+ (f ( ! lock+ face ( ! pallet1 b w\ld be foll[$ by ! jewel p9 n pass+ fully into ! =k1 b /rik+ ! inside face ( ! prong ( ! =k at ab\t ! po9t indicat$ by ! dott$ l9e m4 ,we c see t if ! prong ( ! =k 0 ext5d$ to ab\t ! l5g? indicat$ by ! outl9e at c1 ! action w\ld be z x %\ld be4 ,to practically inve/igate ?is matt] to ! be/ advantage1 we ne$ "s arrangem5t by :i* we c det]m9e ! angul> motion ( ! lev] & also ( ! roll] & escape :eel4 ,to d ?is1 we provide ourselves ) a device :i* has already be5 describ$1 b ( small] size1 = measur+ =k & pallet action4 ,! device to :i* we allude is %[n at ,figs4 #ajd1 #aje & #ajf4 ,fig4 #ajd %[s only ! index h&1 :i* is made ( /eel ab\t #a_/bj ?ick & %ap$ z %[n4 ,! jaws ,b'' are int5d$ to grasp ! pallet /aff by ! not*es e1 & hold by friction4 ,! prongs l l are only to gu>d ! /aff s x w readily ent] ! not* e4 ,! circle d is only to enable u to bett] hold ! h& ,b flat4 ,illu/ration3 ,fig4 #ajd ,,h[ ,,to ,,measure ,,escapem5t ,,angles4 ,f ! c5t] ( ! not*es e to ! tip ( ! index h& ,b' ! l5g? is #b4 ,?is di/ance is also ! radius ( ! index arc ,c4 ,?is index arc is divid$ into ?irty degrees1 ) ?ree or f\r supplem5t>y degrees on ea* side1 z %[n4 ,= measur+ pallet action we only require t5 degrees1 & = roll] action ?irty degrees4 ,! arc ,c1 ,fig4 #aje1 c be made ( brass & is ab\t #a long by wide2 said arc is m\nt$ on a brass wire ab\t #a_/h diamet]1 z %[n at k1 ,fig4 #ajf1 :i* is a view ( ,fig4 #aje se5 9 ! direction ( ! arr[ i4 ,?is wire k ent]s a base %[n at ,d ,e1 ,fig4 #ajf1 :i* is provid$ ) a set-screw at j = hold+ ! index arc at ! prop] height to co9cide ) ! h& ,b4 ,illu/ration3 ,fig4 #aje ,illu/ration3 ,fig4 #ajf ,a good way to get up ! p>ts %[n 9 ,fig4 #ajf is to take a disk ( ?ick %eet brass ab\t #a 9 diamet] & ins]t 9 x a piece ( brass wire ab\t diamet] & #c_/h long1 ?r\gh :i* drill axially a hole to receive ! wire k4 ,aft] ! jaws ,b'' are clamp$ on ! pallet /aff1 we set ! index arc ,c s ! h& ,b' w indicate ! angul> motion ( ! pallet /aff4 ,by plac+ ! index h& ,b on ! balance /aff we c get at ! exact angul> duration ( ! engagem5t ( ! jewel p9 9 ! =k4 ,( c\rse1 x is und]/ood t ?is in/rum5t w also measure ! angles ( impulse & lock4 ,?us1 suppose ! entire angul> motion ( ! lev] f bank to bank is t5 degrees2 to det]m9e h[ mu* ( ?is is lock & h[ mu* impulse1 we set ! index arc ,c s t ! h& ,b' m>ks t5 degrees = ! entire motion ( ! =k1 & :5 ! escapem5t is lock$ we move ! =k f its bank & notice by ! arc ,c h[ _m degrees ! h& indicat$ be=e x pass$ ( its own accord to ! opposite bank4 ,if we h m ?an "o & a half degrees ( lock we h too mu* & %\ld seek to rem$y x4 ,h[8 ,x is j ! answ]s to su* que/ions we propose to give by ! aid ( our big model4 ,,det]m9ation ,,( ,,"r ,,me?ods4 ,be sure y are "r1 !n g ahead1 0 ! advice ( ! celebrat$ ,davie ,crockett4 ,! only tr\ble 9 apply+ ?is motto to wat*mak+ is to "k :5 y are "r4 ,we h also (t5 he>d ! rem>k t !re 0 only "o "r way1 b any numb] ( wrong ways4 ,n[ we are incl9$ to ?9k t mo/ ( ! p :o hold to b "o "r way are *iefly ^? :o believe all ways b _! own ways are wrong4 ,iron-b\nd rules are seldom s\nd ev5 9 e?ics1 & are utt]ly impracticable 9 me*anics4 ,we h se5 _m workm5 :o _h le>n$ to draw a lev] escapem5t ( a giv5 type1 & liv$ firm 9 ! belief t all lev] escapem5ts 7 wrong :i* 7 n made s z to con=m to ?is c]ta9 me?od4 ,"o workman believes 9 equidi/ant lock+s1 ano!r 9 circul> pallets2 ea* /rong 9 ! idea t _! p>ticul> & peculi> me?od ( design+ a lev] escapem5t 0 ! only "o to be tol]at$4 ,! writ] is free to confess t he has se5 lev] escapem5ts ( bo? types1 t is1 circul> pallets & equidi/ant lock+s1 :i* gave excell5t results4 ,ano!r moot$ po9t 9 ! lev] escapem5t is1 to decide betwe5 ! m]its ( ! rat*et & ! club-too? escape :eel4 ,engli% mak]s1 z a rule1 hold to ! rat*et too?1 :ile ,cont95tal & ,am]ican manufactur]s favor ! club too?4 ,! *ief argum5ts 9 favor ( ! rat*et too? are3 7a7 ,x w run )\t oil+ ! pallets2 7b7 9 case ! escape :eel is lo/ or brok5 x is m readily replac$1 z all rat*et-too? escape :eels are alike1 ei!r = circul> pallets or equidi/ant lock+s4 ,! objections urg$ aga9/ x are3 7a7 ,excessive drop2 7b7 ! escape :eel1 be+ frail1 is liable to be injur$ by incompet5t p]sons h&l+ x2 7c7 ?is escapem5t 9 _m in/ances does require to h ! pallets oil$4 ,,escapem5ts ,,comp>$4 7a7 ,t a rat*et-too? escape :eel requires m drop ?an a club too? mu/ be admitt$ )\t argum5t1 z ?is =m ( too? requires f "o-half to ?ree-f\r?s ( a degree m drop ?an a club too?2 7b7 z reg>ds ! frailty ( ! tee? we hold ?is z ( small import1 z any workman :o is compet5t to repair wat*es w\ld nev] injure ! delicate tee? ( an escape :eel2 7c7 rat*et-too? lev] escapem5ts w occasionally ne$ to h ! pallets oil$4 ,! writ] is incl9$ to ?9k t ?is defect c\ld be rem$i$ by prop] c>e 9 select+ ! /one 7ruby or sapphire7 & gr9d+ ! pallets 9 su* a way t ! escape-:eel tee? w n act aga9/ ! foliations ) :i* all cry/all9e /ones are built up4 ,all workm5 :o h _h an ext5d$ exp]i5ce 9 repair "w are well aw>e t !re are "s lev] escapem5ts 9 :i* ! pallets absolutely require oil2 o!rs w seem to get along v nicely )\t4 ,?is applies also to ,am]ican brass club-too? escapem5ts2 h5ce1 we h s mu* cont5tion ab\t oil+ pallets4 ,! writ] does n claim to "k positively t ! pallet /ones are at fault because "s escapem5ts ne$ oil+1 b ! fact mu/ admit ( explanation "s way1 & is ?is n at lea/ a rational solution8 ,all p]sons :o h paid att5tion to cry/allography are aw>e t cry/als are built up1 & h l9es ( cleavage4 ,9 ! manufacture ( hole jewels1 c>e mu/ be tak5 to "w ) ! axis ( cry/allization1 or a smoo? hole _c be obta9$4 ,! advantages claim$ = ! club-too? escapem5t are _m2 among !m may be cit$ 7a7 ! fact t x utilizes a great] arc ( impulse ( ! escape :eel2 7b7 ! impulse be+ divid$ betwe5 ! too? & ! pallet1 p]mits great] p[] to be utiliz$ at ! close ( ! impulse4 ,?is feature we h already expla9$4 ,x is no d\bt true t x is m difficult to mat* a set ( pallets ) an escape :eel ( ! club-too? ord] ?an ) a rat*et too?2 /ill ! writ] ?9ks t ?is objection is ( b little consequ5ce :]e a workman kn[s exactly :at to d & h[ to d x2 9 o!r words1 is sure he is "r1 & c !n g ahead intellig5tly4 ,x is claim$ by "s t all ,am]ican escape :eels ( a giv5 grade are exact duplicates2 b1 z we h previ\sly /at$1 ?is is n exactly ! case1 z !y v>y a trifle4 ,s d ! pallet jewels v>y a little 9 ?ickness & 9 ! angles4 ,suppose we put 9 a new escape :eel & f9d we h on ! entrance pallet too mu* drop1 t is1 ! too? :i* engag$ ?is pallet made a decid$ movem5t =w>d be=e ! too? :i* engag$ ! exit pallet enc\nt]$ ! lock+ face ( said pallet4 ,if we ?or\ghly und]/& ! lev] escapem5t we c see 9 an in/ant if putt+ 9 a ?ick] pallet /one = entrance pallet w rem$y ! defect4 ,"h aga9 we c /udy ! effects ( a *ange 9 our l>ge model bett] ?an 9 an escapem5t no l>g] ?an is 9 an ord9>y wat*4 ,,h[ ,,to ,,set ,,pallet ,,/ones4 ,!re h be5 _m devices br\ght =w>d to aid ! workman 9 adju/+ ! pallet /ones to lev] wat*es4 ,be=e go+ into ! details ( any su* device we %\ld ?or\ghly und]/& exactly :at we desire to accompli%4 ,9 sett+ pallet /ones we mu/ take into consid]ation ! relation ( ! roll] & =k action4 ,z has already be5 expla9$1 ! fir/ ?+ to d is to set ! roll] & =k action z x %\ld be1 )\t reg>d 9 a great degree to pallet action4 ,illu/ration3 ,fig4 #ajg ,to expla91 suppose we h a pallet /one to set 9 a full-plate movem5t4 ,! fir/ ?+ to d is to close ! bank+s s t ! jewel p9 w n pass out ( ! slot 9 ! =k on ei!r side2 !n gradually op5 ! bank+s until ! jewel p9 w pass out4 ,?is w be und]/ood by inspect+ ,fig4 #ajg1 :]e ,a ,a' %[s a lev] =k z if 9 contact ) bo? banks1 & ! jewel p91 repres5t$ at ,b ,b''1 j passes ! angle a c' ( ! =k4 ,! circle describ$ by ! jewel p9 ,b is indicat$ by ! arc e4 ,x is well to put a slight friction "u ! balance rim1 9 ord] t we c try ! fre$om ( ! gu>d p94 ,z a rule1 all ! gu>d p9 ne$s is to be free & n t\* ! roll]4 ,! entire po9t1 z f> z sett+ ! =k & bank+s is conc]n$1 is to h ! =k & roll] action s\nd4 ,= all ord9>y lev] escapem5ts ! angul> motion ( ! lev] bank$ 9 z j describ$ %\ld be ab\t t5 degrees4 ,z expla9$ 9 =m] examples1 if ! =k action is entirely s\nd & ! lev] only vibrates ?r\gh an arc ( n9e degrees1 x is q z well to make ! pallets con=m to ?is arc z to make ! jewel p9 c>ry ! =k ?r\gh full t5 degrees4 ,aga91 if ! lev] vibrates ?r\gh elev5 degrees1 x is z well to make ! pallets con=m to ?is arc4 ,! writ] is well aw>e t _m read]s w cavil at ?is idea & insi/ t ! workman %\ld br+ all ! p>ts "r on ! basis ( t5 degrees =k & lev] action4 ,9 reply we w\ld say t no escapem5t is p]fect1 & x is ! duty ( ! workman to get ! be/ results he c = ! money he gets = ! job4 ,9 ! in/ance giv5 above1 ( ! escapem5t ) n9e degrees ( lev] action1 :5 ! =k work$ all "r1 if we und]took to give ! =k ! t5 degrees dem&$ by ! /ickl] = accuracy we w\ld h to set out ! jewel p9 or l5g!n ! =k1 & to d ei!r w\ld require m "t ?an x w\ld to br+ ! pallets to con=m to ! =k & roll] action4 ,x is j ?is kn[+ h[ & ! decision to act t makes ! diff]5ce 9 ! workman :o is wor? to 8 employ] twelve or tw5ty-five doll>s p] week4 ,we h describ$ in/rum5ts = measur+ ! angle ( =k & pallet action1 b aft] "o has _h exp]i5ce he c judge pretty ne>ly & !n x is seldom necess>y to measure ! angle ( =k action z long z x is ne> ! prop] ?+1 & !n br+ ! pallets to mat* ! escape :eel aft] ! =k & roll] action is z x %\ld be--t is1 ! jewel p9 & =k "w free1 ! gu>d p9 has prop] fre$om1 & ! =k vibrates ?r\gh an arc ( ab\t t5 degrees4 ,usually ! workman c manipulate ! pallets to mat* ! escape :eel s t ! tee? w h ! prop] lock & drop at ! "r in/ant1 & aga9 h ! correct lock on ! next succe$+ pallet4 ,! too? %\ld fall b a slight di/ance be=e ! too? next 9 action locks x1 because all ! angul> motion ! escape :eel makes except :5 9 contact ) ! pallets is j s mu* lo/ p[]1 :i* %\ld g t[>d giv+ motion to ! balance4 ,!re seems to be a little confusion 9 ! use ( ! ^w drop 9 horological phrase1 z x is us$ to express ! act ( p>t+ ( ! too? ) ! pallet4 ,! idea w be se5 by inspect+ ,fig4 #ajh1 :]e we %[ ! too? ,d & pallet ,c z ab\t p>t+ or dropp+4 ,:5 we speak ( bank+ up to ! drop we mean we set ! bank+ screws s t ! tee? w j escape f ea* pallet4 ,by ! t]m fall we mean ! arc ! too? passes ?r\gh be=e ! next pallet is engag$4 ,?is action is also illu/rat$ at ,fig4 #ajh1 :]e ! too? ,d1 aft] dropp+ f ! pallet ,c1 is arre/$ at ! position %[n by ! dott$ outl9e4 ,we designate ?is arc by ! t]m fall1 & we measure ?is motion by its angul> ext5t1 z %[n by ! dott$ radial l9es i f & i g4 ,z we h expla9$1 ?is fall %\ld only ext5d ?r\gh an arc ( "o & a half degrees1 b by close escapem5t mat*+ ?is arc c be r$uc$ to "o degree1 or ev5 a trifle less4 ,illu/ration3 ,fig4 #ajh ,we %all next describe an in/rum5t = hold+ ! escape :eel & pallets :ile adju/+ !m4 ,z %[n at ,fig4 #ajg1 ! =k ,a' is bank$ a little close & ! jewel p9 z %[n w\ld1 9 "s portions1 rub on ,c'1 mak+ a scrap+ s\nd4 ,,h[ ,,to ,,make ,,an ,,escapem5t ,,mat*+ ,,tool4 ,illu/ration3 ,fig4 #aji ,a po9t has n[ be5 rea*$ :]e we c use an escapem5t mat*] to advantage4 ,!re are sev]al good ones on ! m>ket1 b we c make "o v *eaply & also add our own improvem5ts4 ,9 mak+ "o1 ! fir/ ?+ to be provid$ is a movem5t hold]4 ,any ( ! ?ree-jaw types ( su* hold]s w answ]1 provid$ ! jaws hold a movem5t plate p]fectly p>allel ) ! b$ ( ! hold]4 ,?is w be bett] und]/ood by inspect+ ,fig4 #aji1 :i* is a side view ( a device ( ?is k9d se5 edgewise 9 elevation4 ,9 ?is ,b repres5ts ! b$ plate1 :i* supports ?ree sw+ jaws1 %[n at ,c1 ,figs4 #aji & #aaj4 ,! wat* plate is indicat$ by ! p>allel dott$ l9es ,a1 ,fig4 #aji4 ,! seat a ( ! sw+ jaws ,c mu/ hold ! wat* plate ,a exactly p>allel ) ! b$ plate ,b4 ,9 ! *eap movem5t hold]s ^! seats 7a7 are apt to be ( irregul> heights1 & mu/ be correct$ = our purpose4 ,we w take x = grant$ t all ! seats a are ( precisely ! same height1 measur$ f ,b1 & t a wat* plate plac$ 9 ! jaws ,c w be held exactly p>allel ) ! said b$ ,b4 ,we mu/ next provide two pill>s1 %[n at ,d ,e1 ,figs4 #aji & #aaa4 ,^! pill>s furni% support = slid+ c5t]s :i* hold ! top pivots ( ! escape :eel & pallet /aff :ile we are te/+ ! dep?s & adju/+ ! pallet /ones4 ,x w be und]/ood t ^! pill>s ,d ,e are at "r angles to ! plane ( ! b$ ,b1 9 ord] t ! slides l ,g ,n on ! pill>s ,d ,e move exactly v]tical4 ,9 fact1 all ! p>ts mov+ up & d[n %\ld be accurately made1 s z n to de/roy ! dep?s tak5 f ! wat* plate ,a4 ,suppose1 to illu/rate1 t we place ! plate ,a 9 position z %[n1 & ins]t ! cone po9t n1 ,figs4 #aji & #aab1 9 ! pivot hole = ! pallet /aff1 adju/+ ! slide ,g ,n s t ! cone po9t re/s accurately 9 said pivot hole4 ,x is fur!r dem&$ t ! p>ts ,i ,h ,f ,g ,n ,d be s con/ruct$ & adju/$ t ! slid+ c5t] ,i moves truly v]tical1 & t we c *ange ends ) said c5t] ,i & place ! holl[ cone end m1 ,fig4 #aab1 s x w receive ! top pivot ( ! pallet /aff & hold x exactly upright4 ,illu/ration3 ,fig4 #aaj ,illu/ration3 ,fig4 #aaa ,illu/ration3 ,fig4 #aab ,! idea ( ! slid+ c5t] ,i is to p]fectly supply ! place ( ! opposite plate ( ! wat* & give u exactly ! same practical dep?s z if ! p>ts 7 9 _! place betwe5 ! plates ( ! movem5t4 ,! foot ( ! pill> ,d has a flange atta*$1 z %[n at f1 :i* aids 9 hold+ x p]fectly upright4 ,x is well to cut a screw on ,d at ,d'1 & screw ! flange f on su* screw & !n turn ! l[] face ( f flat to aid 9 hav+ ! pill> ,d p]fectly upright4 ,,details ,,( ,,fitt+ ,,up ,,escapem5t ,,mat*]4 ,x is well to fit ! screw ,d' loosely1 s t ! flange f w come p]fectly flat ) ! upp] surface ( ! base plate ,b4 ,! slide ,g ,n on ! pill> ,d c be made ( two pieces ( small brass tube1 "o fitt+ ! pill> ,d & ! o!r ! b> ,f4 ,! slide ,g ,n is held 9 position by ! set screw g1 & ! rod ,f by ! set screw h4 ,illu/ration3 ,fig4 #aac ,illu/ration3 ,fig4 #aad ,! piece ,h c be p]man5tly atta*$ to ! rod ,f4 ,we %[ sep>ate at ,figs4 #aac & #aad ! slide ,g ,n on an enl>g$ scale f ,fig4 #aji4 ,fig4 #aad is a view ( ,fig4 #aac se5 9 ! direction ( ! arr[ e4 ,all jo9ts & movable p>ts %\ld "w free1 9 ord] t ! c5t] ,i may be readily & accurately set4 ,! p>ts ,h ,f are %[n sep>ate & enl>g$ at ,figs4 #aae & #aaf4 ,! piece ,h c be made ( ?ick %eet brass securely atta*$ to ,f 9 su* a way z to br+ ! ,v-%ap$ groove at "r angles to ! axis ( ! rod ,f4 ,x is well to make ! rod ,f ab\t #a_/h 9 diamet]1 :ile ! slid+ c5t] ,i ne$ n be m ?an #a_/af 9 diamet]4 ,! cone po9t n %\ld be h>d5$ to a spr+ temp] & turn$ to a true cone 9 an accurately runn+ wire *uck4 ,illu/ration3 ,fig4 #aae ,illu/ration3 ,fig4 #aaf ,! holl[ cone end m ( ,i %\ld also be h>d5$1 b ?is is be/ done aft] ! holl[ cone is turn$ 94 ,! h>d5+ ( bo? ends %\ld only be at ! tips4 ,! slid+ c5t] ,i c be held 9 ! ,v-%ap$ groove by two light friction spr+s1 z indicat$ at ! dott$ l9es s s1 ,fig4 #aae1 or a flat plate ( ,no4 #bd or #be %eet brass ( ! size ( ,h c be employ$1 z %[n at ,figs4 #aaf & #aag1 :]e o repres5ts ! plate ( ,no4 #bd brass1 p p ! small screws atta*+ ! plate o to ,h1 & k a clamp+ screw to fa/5 ,i 9 position4 ,x w be f\nd t ! two light spr+s s s1 ,fig4 #aae w be ! mo/ satisfactory4 ,! wire legs1 %[n at ,l1 w aid 9 mak+ ! device set /eady4 ,! pill> ,e is provid$ ) ! same slides & o!r p>ts z describ$ & illu/rat$ z atta*$ to ,d4 ,! position ( ! pill>s ,d & ,e are indicat$ at ,fig4 #aaj4 ,illu/ration3 ,fig4 #aag ,illu/ration3 ,fig4 #aah ,we w next tell h[ to flatt5 ,f to keep ,h exactly v]tical4 ,to aid 9 explanation1 we w %[ 7enl>g$7 at ,fig4 #aah ! b> ,f %[n 9 ,fig4 #aji4 ,9 flatt5+ su* pieces to prev5t turn+1 we %\ld cut away ab\t two-fif?s1 z %[n at ,fig4 #aai1 :i* is an end view ( ,fig4 #aah se5 9 ! direction ( ! arr[ c4 ,9 su* flatt5+ we %\ld n only cut away two-fif?s at "o end1 b we mu/ pres]ve ?is proportion f end to end4 ,to aid 9 ?is op]ation we make a fix$ gage ( %eet metal1 %ap$ z %[n at ,i1 ,fig4 #abj4 ,illu/ration3 ,fig4 #aai ,,escapem5t ,,mat*+ ,,device ,,describ$4 ,illu/ration3 ,fig4 #abj ,9 practical con/ruction we fir/ file away ab\t two-fif?s ( ,f & !n gr9d ! flat side on a glass slab to a flat1 ev5 surface &1 ( c\rse1 equal ?ickness f end to end4 ,we reproduce ! sleeve ,g z %[n at ,fig4 #aac z if se5 f ! left & 9 ! direction ( ! axis ( ! b> ,f4 ,to prev5t ! b> ,f turn+ on its axis1 we ins]t 9 ! sleeve ,g a piece ( wire ( ! same size z ,f b ) ?ree-fif?s cut away1 z %[n at y1 ,fig4 #aba4 ,?is piece y is sold]$ 9 ! sleeve ,g s its flat face /&s v]tical4 ,to give s]vice & effici5cy to ! screw h1 we ?ick5 ! side ( ! sleeve ,f by add+ ! /ud w1 ?r\gh :i* ! screw h works4 ,a s(t metal plug goes betwe5 ! screw h & ! b> ,f1 to prev5t ,f be+ cut up & m>r$4 ,x w be se5 t we c place ! top plate ( a full-plate movem5t 9 ! device %[n at ,fig4 #aji & set ! v]tical c5t]s ,i s ! cone po9ts n w re/ 9 ! pivot holes ( ! escape :eel & pallets4 ,x is to be und]/ood t ! l[] side ( ! top plate is plac$ upp]mo/ 9 ! movem5t hold]4 ,illu/ration3 ,fig4 #aba ,if we n[ rev]se ! ends ( ! c5t]s ,i & let ! pivots ( ! escape :eel & pallet /aff re/ 9 ! holl[ cones ( ^! c5t]s ,i1 we h ! escape :eel & pallets 9 precisely ! same position & relation to ea* o!r z if ! l[] plate 0 9 position4 ,x is fur!r to be suppos$ t ! balance is 9 place & ! cock screw$ d[n1 al?\gh ! pres5ce ( ! balance is n absolutely necess>y if ! bank+ screws are set z direct$1 t is1 s ! jewel p9 w j freely pass 9 & out ( ! =k4 ,,h[ ,,to ,,set ,,pallet ,,/ones4 ,we h n[ come to sett+ or manipulat+ ! pallet /ones s !y w act 9 exact conjunction ) ! =k & roll]4 ,to d ?is we ne$ to h ! %ellac :i* holds ! pallet /ones heat$ en\gh to make x pla/ic4 ,! usual way is to heat a piece ( metal & place x 9 close proximity to ! pallets1 or to heat a pair ( pli]s & clamp ! pallet arms to s(t5 ! cem5t4 ,( c\rse1 x is und]/ood t ! movem5t hold] _c be mov$ ab\t :ile ! /ones are be+ manipulat$4 ,! bett] way is to set ! movem5t hold] on a r heavy plate ( glass or metal1 s t ! hold] w n jo/le ab\t2 !n set ! lamp s x w d its duty1 & aft] a little practice ! sett+ ( a pair ( pallet /ones to p]fectly p]=m _! functions w take b a few m9utes4 ,9 fact1 if ! /ones w answ] at all1 ?ree to five m9utes is z mu* "t z "o c\ld well devote to ! adju/m5t4 ,! read] w see t if ! lev] is prop]ly bank$ all he has to d is to set ! /ones s ! lock1 draw & drop are "r1 :5 ! entire escapem5t is z x %\ld be1 & w ne$ no fur!r trial or manipulat+4 ,,*apt] ,,ii4 ,,! ,,cyl9d] ,,escapem5t4 ,!re is always 9 me*anical matt]s an und]ly+ comb9ation ( pr9ciples & relations ( p>ts kn[n z !ory4 ,we (t5 he> ! rem>k made t su* a ?+ may be all "r 9 !ory1 b w n "w 9 practice4 ,?is /atem5t has no f\ndation 9 fact4 ,if a giv5 me*anical device accords /rictly ) !ory1 x w come out all "r practically4 ,m5tal conceptions ( a ma*9e are :at we may t]m _! !oretical exi/5ce4 ,:5 we make draw+s ( a ma*9e m5tally conceiv$1 we comm5ce its me*anical con/ruction1 & if we make su* draw+s to scale1 & add a specification /at+ ! mat]ials to be employ$1 we leave only ! m]e/ me*anical details to be c>ri$ out2 ! bra9 "w is done & only f+] "w rema9s to be execut$4 ,) ^! prelim9>y rem>ks we w take up ! consid]ation ( ! cyl9d] escapem5t inv5t$ by ,rob]t ,graham ab\t ! ye> #agbj4 ,x is "o ( ! two s-call$ frictional re/ dead-beat escapem5ts :i* h come into popul> use1 ! o!r be+ ! duplex4 ,usage1 or1 to put x 9 o!r words1 exp]i5ce d]iv$ f ! actual manufacture ( ! cyl9d] escapem5t1 settl$ ! be/ =ms & proportions ( ! sev]al p>ts ye>s ago4 ,/ill1 mak]s v>y slightly on c]ta9 l9es1 :i* are important = a man :o repairs su* wat*es to "k & be able to c>ry out1 9 ord] to put !m 9 a condition to p]=m z int5d$ by ! manufactur]s4 ,x is n kn[+ ^! l9es :i* leaves ! av]age wat*mak] s mu* at sea4 ,he cuts & moves & %ifts p>ts ab\t to see if dumb luck w n supply ! correction he does n "k h[ to make4 ,?is requisite k does n consi/ s mu* 9 kn[+ h[ to file or gr9d z x does 9 discrim9at+ :]e su* application ( manual dext]ity is to be appli$4 ,& "r "h let u make a rem>k to :i* we w call att5tion aga9 lat] on4 ,! po9t ( ?is rem>k lies 9 ! "q--,h[ _m ( ! s-call$ practical wat*mak]s c\ld tell y :at proportion ( a cyl9d] %\ld be cut away f ! half %ell8 ,h[ _m c\ld expla9 ! diff]5ce betwe5 ! real & app>5t lift8 ,comp>atively few1 & yet a k ( ^! ?+s is z important = a wat*mak] z x is = a surgeon to und]/& ! action ( a man's he>t or ! relations ( ! muscles to ! bones4 ,,ess5tial ,,p>ts ,,( ,,! ,,cyl9d] ,,escapem5t4 ,! cyl9d] escapem5t is made up ( two ess5tial p>ts1 viz43 ! escape :eel & ! cyl9d]4 ,! cyl9d] escape :eel 9 all mod]n wat*es has fifte5 tee?1 al?\gh ,sauni]1 9 8 ,mod]n ,horology1 del9eates a twelve-too? :eel = app>5tly no bett] reason ?an because x 0 m easily drawn4 ,we1 9 ?is treatise1 w consid] bo? ! !oretical action & ! practical con/ruction1 b m p>ticul>ly ! repair ( ?is escapem5t 9 a ?or\gh & complete mann]4 ,at />t+ out1 we w fir/ agree on ! names ( ! sev]al p>ts ( ?is escapem5t1 & to aid u 9 ?is we w ref] to ! accompany+ draw+s1 9 :i* ,fig4 #abb is a side elevation ( a cyl9d] complete & ready to h a balance /ak$ on to x4 ,fig4 #abc %[s ! cyl9d] remov$ f ! balance collet4 ,figs4 #abd & #abe %[ ! upp] & l[] plugs remov$ f ! cyl9d]4 ,fig4 #abf is a horizontal section ( ,fig4 #abb on ! l9e i4 ,fig4 #abg is a side view ( "o too? ( a cyl9d] escape :eel z if se5 9 ! direction ( ! arr[ f 9 ,fig4 #abf4 ,fig4 #abh is a top view ( two tee? ( a cyl9d] escape :eel4 ,! names ( ! sev]al p>ts usually employ$ are z foll[s3 ,a4--,upp] or ,ma9 ,%ell4 ,a'4--,half ,%ell4 ,a''4--,column4 ,a'''4--,small ,%ell4 ,b ,b' ,b''4--,balance ,collet4 ,g4--,upp] ,plug4 ,h4--,l[] ,plug4 g4--,entrance ,lip ( ,cyl9d]4 h4--,exit ,lip ( ,cyl9d]4 c4--,bank+ ,slot4 ,c4--,too?4 ,d4--,u arm4 ,e4--,/alk ( ,pill>4 ,i4--,u space4 l4--,po9t ( ,too?4 k4--,heel ( ,too?4 ,! cyl9d] escapem5t has two engagem5ts or actions1 dur+ ! passage ( ea* too?2 t is1 "o on ! outside ( ! cyl9d] & "o on ! inside ( ! %ell4 ,z we %all %[ lat] on1 ! cyl9d] escapem5t is ! only positively dead-beat escapem5t 9 use1 all o!rs1 ev5 ! duplex1 hav+ a slight recoil dur+ ! process ( escap+4 ,:5 ! too? ( a cyl9d] escape :eel :ile p]=m+ its functions1 /rikes ! cyl9d] %ell1 x re/s dead on ! out] or inn] surface ( ! half %ell until ! action ( ! balance spr+ has br\ght ! lip ( ! cyl9d] s t ! impulse face ( ! too? comm5ces to imp>t motion or p[] to ! balance4 ,illu/ration3 ,fig4 #abb ,illu/ration3 ,fig4 #abc ,illu/ration3 ,fig4 #abd ,illu/ration3 ,fig4 #abe ,illu/ration3 ,fig4 #abf ,illu/ration3 ,fig4 #abg ,illu/ration3 ,fig4 #abh ,mo/ writ]s on horological matt]s t]m ?is act ! lift1 :i* "n 0 no d\bt acquir$ :5 escapem5ts 7 *iefly conf9$ to p5dulum clocks4 ,v little ?\ght on ! matt] w %[ any p]son :o inspects ,fig4 #abf t if ! too? ,c is releas$ or escapes f ! inside ( ! half %ell ( ! cyl9d] ,a1 said cyl9d] mu/ turn or revolve a little 9 ! direction ( ! arr[ j1 & also t ! next succe$+ too? ( ! escape :eel w engage ! cyl9d] on ! outside ( ! half %ell1 fall+ on ! dead or neutral portion ( said cyl9d]1 to re/ until ! hairspr+ causes ! cyl9d] to turn 9 ! opposite direction & p]mitt+ ! too? n[ re/+ on ! outside ( ! cyl9d] to assume ! position %[n on ! draw+4 ,! fir/ problem 9 our consid]ation ( ! !oretical action ( ! cyl9d] escapem5t1 is to arrange ! p>ts we h describ$ s z to h ^! two movem5ts ( ! escape :eel ( l angul> values4 ,to expla9 :at we mean by ?is1 we mu/ premise by say+1 t z our escape :eel has fifte5 tee? & we make ea* too? give two impulses 9 alt]nate directions we mu/ arrange to h ^! half-too? movem5ts exactly alike1 or1 z /at$ above1 ( equal angul> values2 & also ea* impulse mu/ convey ! same p[] or =ce to ! balance4 ,all escape :eels ( fifte5 tee? act+ by half impulses mu/ impel ! balance dur+ twelve degrees 7m9us ! drop7 ( escape-:eel action2 or1 9 o!r words1 :5 a too? passes out ( ! cyl9d] f ! position %[n at ,fig4 #abf1 ! =m ( ! impulse face ( ! too? & ! %ape ( ! exit lip ( ! cyl9d] mu/ be su* dur+ twelve degrees 7less ! drop7 ( ! angul> motion ( ! escape :eel4 ,! entire p[] ( su* an escape :eel is devot$ to giv+ impulse to ! balance4 ,! ext5t ( angul> motion ( ! balance dur+ su* impulse is1 z previ\sly /at$1 t]m$ ! lift+ angle4 ,?is lift+ angle is by horological writ]s aga9 divid$ into real & app>5t lifts4 ,?is la/ division is only an imag9>y "o1 z ! real lift is ! "o to be /udi$ & expresses ! arc ?r\gh :i* ! impulse face ( ! too? impels ! balance dur+ ! act ( escap+1 & s1 z we %all subsequ5tly %[1 %\ld no m be c\nt$ ?an 9 ! deta*$ lev] escapem5t1 :]e a precisely simil> condition exi/s1 b is nev] consid]$ or discuss$4 ,we %all = ! pres5t take no note ( ?is lift+ angle1 b conf9e ourselves to ! problem j nam$1 ( s arrang+ & design+ our escape-:eel tee? & cyl9d] t ea* half ( ! too? space %all give equal impulses to ! balance ) ! m9imum ( drop4 ,to d ?is we w make a c>eful draw+ ( an escape-:eel too? & cyl9d] on an enl>g$ scale2 our me?od ( mak+ su* draw+s w be on a new & orig9al sy/em1 :i* is v simple yet complete4 ,,draw+ ,,! ,,cyl9d] ,,escapem5t4 ,all horological--& = t matt] all me*anical--draw+s are bas$ on two sy/ems ( measurem5ts3 7#a7 ,l9e> ext5t2 7#b7 angul> movem5t4 ,= ! fir/ measurem5t we adopt ! in* & its decimals2 = ! second we adopt degrees1 m9utes & seconds4 ,= measur+ ! latt] ! usual plan is to employ a protractor1 :i* s]ves ! d\ble purpose ( enabl+ u to lay (f & del9eate any angle & also to measure any angle obta9$ by ! graphic me?od1 & x is ?us by ?is graphic me?od we propose to solve v simply "s ( ! mo/ ab/ruce problems 9 horological del9eations4 ,z an in/ance1 we propose to draw our cyl9d] escapem5t ) no o!r in/rum5ts ?an a /eel /raight-edge1 %[+ "o-hundr$?s ( an in*1 & a pair ( divid]s2 ! degree measurem5t be+ obta9$ f arcs ( sixty degrees ( radii1 z w be expla9$ fur!r on4 ,9 describ+ ! me?od = draw+ ! cyl9d] escapem5t we %all make a radical dep>ture f ! sy/ems usually laid d[n 9 text-books1 & seek to simplify ! =mulas :i* h h]et(ore be5 giv5 = su* del9eations4 ,9 consid]+ ! cyl9d] escapem5t we %all pursue an analytical c\rse & /rive to build up f ! und]ly+ pr9ciples4 ,9 ! draw+s = ?is purpose we %all comm5ce ) "o hav+ an escape :eel ( #aj radius1 & our fir/ ef=t w be ! prim>y draw+ %[n at ,fig4 #abi4 ,"h we e/abli% ! po9t ,a = ! c5t] ( our escape :eel1 & f ?is c5t] sweep ! %ort arc a a ) a #aj radius1 to repres5t ! circumf]5ce ( our escape :eel4 ,f ,a we draw ! v]tical l9e ,a ,b1 & f ! int]section ( said l9e ) ! arc a a we lay (f twelve degree spaces on ea* side ( ! l9e ,a ,b on said arc a & e/abli% ! po9ts b c4 ,f ,a z a c5t] we draw ?r\gh ! po9ts b c ! radial l9es b' c'4 ,to def9e ! face ( ! incl9e to ! tee? we set our divid]s to ! radius ( any ( ! conv5i5t arcs ( sixty degrees :i* we h provid$1 & sweep ! arc t t4 ,f ! int]section ( said arc ) ! l9e ,a b' we lay (f on said arc sixty-f\r degrees & e/abli% ! po9t g & draw ! l9e b g4 ,:y we take sixty-f\r degrees = ! angle ,a b g w be expla9$ lat] on1 :5 we are discuss+ ! angul> motion ( ! cyl9d]4 ,by divid+ ! elev5? degree f ! po9t b on ! arc a a into ?irds & tak+ two ( !m1 we e/abli% ! po9t y & draw ! radial l9e ,a y'4 ,:]e ?is l9e ,a y' int]sects ! l9e b g we "n ! po9t n1 & 9 x is locat$ ! po9t ( ! escape-:eel too?4 ,t portion ( ! l9e b g :i* lies betwe5 ! po9ts b & n repres5ts ! measure ( ! inn] diamet] ( ! cyl9d]1 & also ! l5g? ( ! *ord ( ! arc :i* r\nds ! impulse face ( ! too?4 ,we divide ! space b n into two equal portions & e/abli% ! po9t e1 :i* locates ! position ( ! c5t] ( ! cyl9d]4 ,f ,a z a c5t] & ?r\gh ! po9t e we sweep ! arc e' e'1 & x is on ?is l9e t ! po9ts e/abli%+ ! c5t] ( ! cyl9d] w 9 e in/ance be locat$4 ,f ,a z a c5t]1 ?r\gh ! po9t n we sweep ! arc k1 & on ?is l9e we locate ! po9ts ( ! escape-:eel tee?4 ,= del9eat+ ! curv$ impulse faces ( ! escape-:eel tee? we draw f ! po9t e & at "r angles to ! l9e b g ! l9e e o4 ,we next take 9 our divid]s ! radius ( ! arc k1 & sett+ "o leg at ei!r ( ! po9ts b or n1 e/abli% ) ! o!r leg ! po9t p' on ! l9e e o1 & f ! po9t p' z a c5t] we sweep ! arc b v n1 :i* def9es ! curve ( ! impulse faces ( ! tee?4 ,f ,a z a c5t] ?r\gh ! po9t p' we sweep ! arc p1 & 9 all in/ances :]e we desire to del9eate ! curv$ face ( a too? we locate ei!r ! position ( ! po9t or ! heel ( su* too?1 & sett+ "o leg ( our divid]s at su* po9t1 ! o!r leg re/+ on ! arc p1 we e/abli% ! c5t] f :i* to sweep ! arc def9+ ! face ( said too?4 ,,advantages ,,ga9$ ,,9 ,,%ap+4 ,! reason = giv+ a curv$ =m to ! impulse face ( ! tee? ( cyl9d] escape :eels are some:at intricate1 & ! problem involves sev]al factors4 ,t !re are advantages 9 s %ap+ ! incl9e or impulse face is conc$$1 we believe1 by all rec5t manufactur]s4 ,! *ief b5efit d]iv$ f su* curv$ impulse faces w be evid5t aft] a little ?\ght & /udy ( ! situation & relation ( p>ts z %[n 9 ,fig4 #abi4 ,x w be se5 on inspection t ! angul> motion imp>t$ to ! cyl9d] by ! impulse face ( ! too? :5 curv$ z %[n1 is great] dur+ ! fir/ half ( ! twelve degrees ( escape-:eel action ?an dur+ ! la/ half1 ?us giv+ ! escape :eel ! advantage at ! "t ! balance spr+ increases its resi/ance to ! passage ( ! escape-:eel too? across ! lip ( ! cyl9d]4 ,or1 9 o!r words1 z ! ratio ( resi/ance ( ! balance spr+ increases1 9 a l ratio ! curv$ =m ( ! impulse face ( ! too? gives great] p[] to ! escape-:eel action 9 proportion to ! angul> motion ( ! escape :eel4 ,h5ce1 9 actual s]vice x is f\nd t cyl9d] wat*es ) curv$ impulse planes to ! escape-:eel tee? are less liable to set 9 ! pocket ?an ! tee? hav+ /raight impulse faces4 ,,! ,,out] ,,diamet] ,,( ,,! ,,cyl9d]4 ,illu/ration3 ,fig4 #abi ,to def9e ! rema9d] ( ! =m ( our escape-:eel too? we w next del9eate ! heel4 ,to d ?is we fir/ def9e ! out] diamet] ( our cyl9d]1 :i* is ! ext5t f ! po9t n to c1 & aft] draw+ ! l9e n c we halve ! space & e/abli% ! po9t x1 f :i* po9t z a c5t] we sweep ! circle w w1 :i* def9es ! out] circumf]5ce ( our cyl9d]4 ,) our divid]s set to embrace ! ext5t f ! po9t n to ! po9t c we set "o leg at ! po9t b1 & ) ! o!r leg e/abli% on ! arc k ! po9t h4 ,we next draw ! l9e b h1 & f ! po9t b draw ! l9e b f at "r angle to ! l9e b h4 ,our object = draw+ ^! l9es is to def9e ! heel ( our escape-:eel too? by a "r angle l9e tang5t to ! circle w1 f ! po9t b2 :i* circle w repres5ts ! curve ( ! out] circumf]5ce ( ! cyl9d]4 ,we %ape ! po9t ( ! too? z %[n to give x ! prop] /ability1 & draw ! full l9e j to a curve f ! c5t] ,a4 ,we h n[ def9$ ! =m ( ! upp] face ( ! too?4 ,h[ to del9eate ! ,u arms w be tak5 up lat] on1 z1 9 ! pres5t case1 ! necess>y l9es w\ld confuse our draw+4 ,we w\ld "h take ! opportunity to say t !re is a great latitude tak5 by mak]s z reg>ds ! ext5t ( angul> impulse giv5 to ! cyl9d]1 or1 z x is t]m$1 ! actual lift4 ,?is latitude gov]ns to a great ext5t ! angle ,a b g1 :i* we gave z sixty-f\r degrees 9 our draw+4 ,x is well to und]/& t ! use ( sixty-f\r degrees is bas$ on no h>d-&-fa/ rules1 b v>ies back & =?1 accord+ z a great] or less] angle ( impulse or lift is employ$4 ,9 practical work%op usage ! impulse angle is probably m easily e/imat$ by ! ratio betwe5 ! diamet] ( ! cyl9d] & ! measur$ 7by l9eal measure7 height ( ! impulse plane4 ,or1 to be m explicit1 we measure ! radial ext5t f ! c5t] ,a betwe5 ! arcs a k on ! l9e ,a b1 & use ?is = comp>ison ) ! out] diamet] ( ! cyl9d]4 ,we c readily see t z we increase ! height ( ! heel ( ! impulse face ( our too? we mu/ also increase ! angle ( impulse imp>t$ to ! cyl9d]4 ,) ! advantages ( accurate micromet] calip]s n[ possess$ by ! horological /ud5t x is an easy matt] to get at ! angul> ext5t ( ! real lift ( any cyl9d]4 ,! advantage ( su* measur+ in/rum5ts is also made manife/ 9 det]m9+ :5 ! prop] proportion ( ! cyl9d] is cut away = ! half %ell4 ,illu/ration3 ,fig4 #acj ,9 ! old] me?ods ( wat*mak+ x 0 a v common rule to say1 let ! height ( ! incl9e ( ! too? be "o-sev5? ( ! out] diamet] ( ! cyl9d]1 & at ! same "t ! trade 0 furni%$ ) no tools except a clumsy d\zieme gage2 b ) micromet] calip]s :i* read to "o-?\s&?s ( an in* su* rules c be def9itely c>ri$ into effect & n left to guess "w4 ,let u comp>e ! old me?od ) ! new3 ,suppose we h a new cyl9d] to put 92 we h ! old escape :eel1 b ! =m] cyl9d] is gone4 ,! old-/yle workman w\ld take a r\nd broa* & calculate ! size ( ! cyl9d] by f9d+ a place :]e ! broa* w\ld j g betwe5 ! tee?1 & ! size ( ! broa* at ?is po9t 0 suppos$ to be ! out] diamet] ( ! cyl9d]4 ,by our me?od we measure ! diamet] ( ! escape :eel 9 ?\s&?s ( an in*1 & f ?is size calculate exactly :at ! diamet] ( ! new cyl9d] %\ld be 9 ?\s&?s ( an in*4 ,suppose1 to fur!r c>ry out our comp>ison1 ! escape :eel :i* is 9 ! wat* has tee? :i* h be5 /on$ (f to p]mit ! use ( a cyl9d] :i* 0 too small inside1 or1 9 fact1 ( a cyl9d] too small = ! wat*3 9 ?is case ! broa* sy/em w\ld only add to ! tr\ble & give u a cyl9d] :i* w\ld p]mit too mu* inside drop4 ,,draw+ ,a ,,cyl9d]4 ,we h already in/ruct$ ! pupil h[ to del9eate a cyl9d] escape :eel too? & we w next describe h[ to draw a cyl9d]4 ,z already /at$1 ! c5t] ( ! cyl9d] is plac$ to co9cide ) ! c5t] ( ! *ord ( ! arc :i* def9es ! impulse face ( ! too?4 ,consequ5tly1 if we design a cyl9d] escape :eel too? z previ\sly describ$1 & sett+ "o leg ( our compasses at ! po9t e :i* is situat$ at ! c5t] ( ! *ord ( ! arc :i* def9es ! impulse face ( ! too? & ?r\gh ! po9ts d & b we def9e ! inside ( our cyl9d]4 ,we next divide ! *ord d b into eight p>ts & set our divid]s to five ( ^! p>ts1 & f e z a c5t] sweep ! circle h & def9e ! outside ( our cyl9d]4 ,f ,a z a c5t] we draw ! radial l9e ,a e'4 ,at "r angles to ! l9e ,a e' & ?r\gh ! po9t e we draw ! l9e f e z a c5t]1 & ) our divid]s set to ! radius ( any ( ! conv5i5t arcs :i* we h divid$ into sixty degrees1 we sweep ! arc i4 ,:]e ?is arc int]sects ! l9e f we t]m ! po9t k1 & f ?is po9t we lay (f on ! arc i #bbj degrees1 & draw ! l9e l e l'1 :i* we see co9cides ) ! *ord ( ! impulse face ( ! too?4 ,we set our divid]s to ! same radius by :i* we sweep ! arc i & set "o leg at ! po9t b = a c5t] & sweep ! arc j'4 ,if we measure ?is arc f ! po9t j' to int]section ( said arc j' ) ! l9e l we w f9d x to be sixty-f\r degrees1 :i* acc\nts = our tak+ ?is numb] ( degrees :5 we def9$ ! face ( our escape-:eel too?1 ,fig4 #abi4 ,!re is no reason :y we %\ld take tw5ty-degrees = ! angle k e l except t ! practical con/ruction ( ! l>g] sizes ( cyl9d] wat*es has e/abli%$ ! fact t ?is is ab\t ! "r angle to employ1 :ile 9 small] wat*es x frequ5tly runs up z high z tw5ty-five4 ,al?\gh ! cyl9d] is seem+ly a v simple escapem5t1 x is really a v ab/ruce "o to foll[ out s z to become famili> ) all ( its actions4 ,,! ,,cyl9d] ,,prop] ,,consid]$4 ,illu/ration3 ,fig4 #aca ,we w n[ proce$ & consid] ! cyl9d] prop]1 & to aid u 9 und]/&+ ! position & relation ( ! p>ts we ref] to ,fig4 #aca1 :]e we repeat ! circles d & h1 %[n 9 ,fig4 #acj1 :i* repres5ts ! inside & outside ( ! cyl9d]4 ,we h "h also repeat$ ! l9e f ( ,fig4 #acj z x cuts ! cyl9d] 9 half1 t is1 divides x into two segm5ts ( #ahj degrees ea*4 ,if we conceive ( a cyl9d] 9 :i* j "o-half is cut away1 t is1 ! lips are b\nd$ by /raight radial l9es1 we c also conceive ( ! relation & position ( ! p>ts %[n 9 ,fig4 #acj4 ,! fir/ position ( :i* we %\ld take cognizance is1 ! too? ,d is mov$ back to ! left s z to re/ on ! outside ( our cyl9d]4 ,! cyl9d] is also suppos$ to /& s t ! lips correspond to ! l9e f4 ,on press+ ! too? ,d =w>d ! incl9e ( ! too? w\ld attack ! entrance lip ( ! cyl9d] at j ab\t ! c5t] ( ! curv$ impulse face1 imp>t+ to ! cyl9d] tw5ty degrees ( angul> motion1 b ! po9t ( ! too? at d w\ld exactly enc\nt] ! inn] angle ( ! exit lip1 & ( c\rse ! cyl9d] w\ld af=d no re/ = ! too?2 h5ce1 we see ! importance ( n cutt+ away too mu* ( ! half %ell ( ! cyl9d]4 ,b be=e we fur!r consid] ! action ( ! too? ,d 9 its action z x passes ! exit lip ( ! cyl9d] we mu/ f9i% ) ! action ( ! too? on ! entrance lip4 ,a v little ?\ght & /udy ( ,fig4 #acj w conv9ce u t ! incl9e ( ! too? z x ent]s ! cyl9d] w comm5ce at t1 ,fig4 #acj1 b at ! close ( ! action ! too? p>ts f ! lip on ! inn] angle4 ,n[ x is evid5t t x w\ld require great] =ce to propel ! cyl9d] by its inn] angle ?an by ! out] "o4 ,to comp5sate = ?is we r\nd ! edge ( ! entrance lip s t ! action ( ! too? in/ead ( comm5c+ on ! out] angle comm5ces on ! c5t] ( ! edge ( ! entrance lip & also ends its action on ! c5t] ( ! entrance lip4 ,to give angul> ext5t en\gh to ! %ell ( ! cyl9d] to all[ = r\nd+ & also to af=d a secure re/ = ! too? inside ! cyl9d]1 we add six degrees to ! angul> ext5t ( ! entrance lip ( ! cyl9d] %ell1 z indicat$ on ! arc o'1 ,fig4 #aca1 ?ree ( ^! degrees be+ absorb$ = r\nd+ & ?ree to insure a dead re/ = ! too? :5 x ent]s ! cyl9d]4 ,,:y ,,! ,,angul> ,,ext5t ,,is ,,increas$4 ,)\t r\nd+ ! exit lip ! action ( ! too? on its exit w\ld be entirely on ! inn] angle ( ! %ell4 ,to obviate ?is x is ! usual practice to increase ! angul> ext5t ( ! cyl9d] t5 degrees1 z %[n on ! arc o' betwe5 ! l9es f & p1 ,fig4 #aca4 ,:y we %\ld all[ t5 degrees on ! exit lip & b six degrees on ! entrance lip w be und]/ood by obs]v+ ,fig4 #acj1 :]e ! radial l9es s & r %[ ! ext5t ( angul> motion ( ! cyl9d]1 :i* w\ld be lo/ if ! too? comm5c$ to act on ! inn] angle & end$ on ! out] angle ( ! exit lip4 ,?is arc is a little ov] six degrees1 & if we add a trifle ov] ?ree degrees = r\nd+ we w\ld acc\nt = ! t5 degrees betwe5 ! l9es f & p1 ,fig4 #aca4 ,x w n[ be se5 t ! angul> ext5t is #aif degrees4 ,if we draw ! l9e w we c see 9 :at proportion ! measurem5t %\ld be made betwe5 ! out] diamet] ( ! cyl9d] & ! measure ( ! half %ell4 ,x w be se5 on measurem5t t ! di/ance betwe5 ! c5t] e & ! l9e w is ab\t "o-fifte5? "p ( ! out] diamet] ( ! cyl9d] & consequ5tly ) a cyl9d] :i* measures #de_/ajjj ( an in* 9 diamet]1 n[ ! half %ell %\ld measure half ( ! entire diamet] ( ! cyl9d] plus "o-fifte5? "p ( su* diamet]1 or #be ?\s&?s ( an in*4 ,aft] ^! proportions are und]/ood & ! draw+ made1 ! eye w get accu/om$ to judg+ pretty ne> :at is requir$2 b mu* ! saf] plan is to measure1 :]e we h ! prop] tools = do+ s4 ,mo/ workm5 h an idea t ! dep? or di/ance at :i* ! cyl9d] is set f ! escape :eel is a matt] ( adju/m5t2 :ile ?is is true to a c]ta9 ext5t1 /ill !re is really only "o position = ! c5t] ( ! cyl9d]1 & t is s t ! c5t] ( ! pivot hole co9cides exactly ) ! c5t] ( ! *ord to ! curve ( ! impulse face ( ! too? or ! po9t e1 ,fig4 #acj4 ,any adju/m5t or mov+ back & =? ( ! *>iot to *ange ! dep? c\ld only be dem&$ :]e !re 0 "s fault exi/+ 9 ! cyl9d] or :]e x _h be5 mov$ out ( its prop] place by "s g5ius z an exp]im5t 9 cyl9d] dep?s4 ,x w be evid5t on obs]v+ ! draw+ at ,fig4 #aca t :5 ! cyl9d] is p]=m+ an arc ( vibration1 z soon z ! entrance lip has pass$ ! po9t indicat$ by ! radial l9e e x ! po9t ( ! escape-:eel too? w comm5ce to act on ! cyl9d] lip & cont9ue to d s ?r\gh an arc ( =ty degrees1 or f ! l9es x to l4 ,,mak+ ,a ,,work+ ,,model4 ,to practically /udy ! action ( ! cyl9d] escapem5t x is well to make a work+ model4 ,x is n necess>y t su* a model %\ld conta9 an entire escape :eel2 all t is really requir$ is two tee? cut out ( brass ( ! prop] =ms & proportions & atta*$ to ! end ( an arm #d-g_/h long ) /uds rivet$ to ! ,u arms to support ! tee?4 ,?is ,u arm is atta*$ to ! long arm we h j m5tion$4 ,a flat r+ ( heavy %eet brass is %ap$ to repres5t a %ort transv]se section ( a cyl9d]4 ,?is segm5t is m\nt$ on a yoke :i* turns on pivots4 ,9 mak+ su* a model we c employ all ! proportions & exact =ms ( ! l>g] draw+s made on a t5-in* radius4 ,su* a model becomes ( great s]vice 9 le>n+ ! importance ( prop]ly %ap+ ! lips ( ! cyl9d]4 ,& "r "h we beg to call att5tion to ! fact t 9 ! ord9>y repair %op ! prop] %ape ( cyl9d] lips is entirely neglect$4 ,,prop] ,,%ape ,,( ,,cyl9d] ,,lips4 ,! workman buys a cyl9d] & :e!r ! prop] am\nt is cut away f ! half %ell1 or ! lips1 ! correct =m is entirely ignor$1 & /ill c>eful att5tion to ! =m ( ! cyl9d] lips adds full t5 p] c5t4 to ! effici5cy ( ! motive =ce z appli$ to ! cyl9d]4 ,9 mak+ /udy draw+s ( ! cyl9d] escapem5t x is n necess>y to employ pap] s l>ge t we c e/abli% ^u x ! c5t] ( ! arc :i* repres5ts ! p]iph]y ( our escape :eel1 z we h at our disposal two plans by :i* ?is c be obviat$4 ,fir/1 plac+ a bit ( bri/ol bo>d on our draw+-bo>d 9 :i* we c set "o leg ( our divid]s or compasses :5 we sweep ! p]iph]al arc :i* we use 9 our del9eations2 second1 mak+ ?ree arcs 9 brass or o!r %eet metal1 viz43 ! p]iph]y ( ! escape :eel1 ! arc pass+ ?r\gh ! c5t] ( ! *ord ( ! arc ( ! impulse face ( ! too?1 & ! arc pass+ ?r\gh ! po9t ( ! escape-:eel too?4 ,( ^! plans we favor ! "o ( /ick+ a bit ( c>dbo>d on ! draw+ bo>d outside ( ! pap] on :i* we are mak+ our draw+4 ,illu/ration3 ,fig4 #acb ,at ,fig4 #acb we %[ ! position & relation ( ! sev]al p>ts j z ! too? passes into ! %ell ( ! cyl9d]1 leav+ ! lip ( ! cyl9d] j z ! too? p>t$ ) x4 ,! half %ell ( ! cyl9d] z %[n occupies #aif degrees or ! l>g] arc embrac$ betwe5 ! radial l9es k & l4 ,9 draw+ ! entrance lip ! act+ face is made almo/ id5tical ) a radial l9e except to r\nd ! corn]s = ab\t "o-?ird ! ?ickness ( ! cyl9d] %ell4 ,no portion1 h[ev]1 ( ! lip c be consid]$ z a /raight l9e1 b might be describ$ z a flatt5$ curve4 ,illu/ration3 ,fig4 #acc ,a little /udy ( :at w\ld be requir$ to get ! be/ results aft] mak+ su* a draw+ w aid ! pupil 9 arriv+ at ! prop] %ape1 especially :5 he rememb]s t ! ?ickness ( ! cyl9d] %ell ( a twelve-l9e wat* is only ab\t five "o-?\s&?s ( an in*4 ,b because ! p>ts are small we %\ld n %irk ! problem ( gett+ ! mo/ we possibly c out ( a cyl9d] wat*4 ,! ext5t ( arc betwe5 ! radial l9es k f1 z %[n 9 ,fig4 #acb1 is f\r degrees4 ,al?\gh 9 =m] draw+s we %[$ ! angul> ext5t add$ z six degrees1 z we %[ ! lip m 9 ,fig4 #acb1 two degrees are lo/ 9 r\nd+4 ,! space k f on ! egress or exit side is int5d$ to be ab\t f\r degrees1 :i* %[s ! ext5t ( lock4 ,we %[ at ,fig4 #acc ! too? ,d j hav+ pass$ out ( ! cyl9d]1 hav+ p>t$ ) ! exit lip p4 ,9 mak+ ?is draw+ we proce$ z ) ,fig4 #acb by e/abli%+ a c5t] = our radius ( #aj outside ( our draw+ pap] & draw+ ! l9e ,a ,a to su* c5t] & sweep+ ! arcs a b c4 ,we e/abli% ! po9t e1 :i* repres5ts ! c5t] ( our cyl9d]1 z be=e4 ,we take ! space to repres5t ! radial ext5t ( ! outside ( our cyl9d] 9 our divid]s & f e z a c5t] sweep a f9e p5cil l9e1 repres5t$ by ! dott$ l9e t 9 our draw+2 & :]e ?is circle int]sects ! arc a we "n x ! po9t s2 & x is at ?is po9t ! heel ( our escape-:eel too? mu/ "p ) ! exit lip ( ! cyl9d]4 ,f e z a c5t] & ?r\gh ! po9t s we draw ! l9e e l''4 ,) our divid]s set to ! radius ( any conv5i5t arc :i* we h divid$ into degrees1 we sweep ! %ort arc d'4 ,! int]section ( ?is arc ) ! l9e e l'' we "n ! po9t u2 & f e z a c5t] we draw ! radial l9e e u f'4 ,we place ! lett] f'' 9 connection ) ?is l9e because x 7! l9e7 be>s ! same relations to ! half %ell ( ! cyl9d] %[n 9 ,fig4 #acc t ! l9e f does to ! half %ell 7,d7 %[n 9 ,fig4 #acb4 ,we draw ! l9e f'' f'''1 ,fig4 #acc1 :i* divides ! cyl9d] into two segm5ts ( #ahj degrees ea*4 ,we take ! same space 9 our divid]s ) :i* we swept ! int]ior ( ! cyl9d] 9 ,fig4 #acb & sweep ! circle v1 ,fig4 #acc4 ,f e z a c5t] we sweep ! %ort arc d''1 ,fig4 #acc1 & f its int]section ( ! l9e f'' we lay (f six degrees on said arc d'' & draw ! l9e e' k''1 :i* def9es ! angul> ext5t ( our entrance lip to ! half %ell ( ! cyl9d] 9 ,fig4 #acc4 ,we draw ! full l9es ( ! cyl9d] z %[n4 ,we next del9eate ! heel ( ! too? :i* has j pass$ out ( ! cyl9d]1 z %[n at ,d'1 ,fig4 #acc4 ,we n[ h a draw+ %[+ ! position ( ! half %ell ( ! cyl9d] j z ! too? has pass$ ! exit lip4 ,?is draw+ also repres5ts ! position ( ! half %ell ( ! cyl9d] :5 ! too? re/s aga9/ x on ! outside4 ,if we %\ld make a draw+ ( an escape-:eel too? %ap$ exactly z ! "o %[n at ,fig4 #acb & ! po9t ( ! too? re/+ at x1 we w\ld %[ ! position ( a too? enc\nt]+ ! cyl9d] aft] a too? :i* has be5 engag$ 9 ! inside ( ! %ell has pass$ out4 ,by foll[+ ! in/ructions n[ giv51 we c del9eate a too? 9 any ( its relations ) ! cyl9d] %ell4 ,,del9eat+ ,,an ,,escape-,,:eel ,,too? ,,:ile ,,9 ,,action4 ,we w n[ g ?r\gh ! op]ation ( del9eat+ an escape-:eel too? :ile 9 action4 ,! position we %all assume is ! "o 9 :i* ! cyl9d] & escape-:eel too? are 9 ! relation ( ! passage ( half ! impulse face ( ! too? into ! cyl9d]4 ,to d ?is is simple en\gh3 ,we fir/ produce ! arcs a b c1 ,fig4 #acc1 z direct$1 & !n proce$ to del9eate a too? z 9 previ\s in/ances4 ,to del9eate our cyl9d] 9 ! position we h assum$ above1 we take ! space betwe5 ! po9ts e d 9 our divid]s & sett+ "o leg at d e/abli% ! po9t g1 to repres5t ! c5t] ( our cyl9d]4 ,if we !n sweep ! circle h f ! c5t] ( g we def9e ! inn] surface ( ! %ell ( our cyl9d]4 ,/rictly speak+1 we h n assum$ ! position we /at$1 t is1 ! impulse face ( ! too? z pass+ half way into ! cyl9d]4 ,to comply /rictly ) our /atem5t1 we divide ! *ord ( ! impulse face ( ! too? ,a into eight equal spaces1 z %[n4 ,n[ z ea* ( ^! spaces repres5t ! ?ickness ( ! cyl9d]1 if we take 9 our divid]s f\r ( ^! spaces & half ( ano!r1 we h ! radius ( a circle pass+ ! c5t] ( ! cyl9d] %ell4 ,consequ5tly1 if ) ?is space 9 our divid]s we set ! leg at d1 we e/abli% on ! arc b ! po9t i4 ,we locate ! c5t] ( our cyl9d] :5 "o-half ( an ent]+ too? has pass$ into ! cyl9d]4 ,if n[ f ! new c5t] ) our divid]s set at f\r ( ! spaces into :i* we h divid$ ! l9e e f we c sweep a circle repres5t+ ! inn] surface ( ! cyl9d] %ell1 & by sett+ our divid]s to five ( ^! spaces we c1 f i z a c5t]1 sweep an arc repres5t+ ! outside ( ! cyl9d] %ell4 ,= all purposes ( practical /udy ! del9eation we %[ at ,fig4 #acc is to be pref]r$1 because1 if we c>ry out all ! details we h describ$1 ! l9es w\ld become confus$4 ,we set our divid]s at five ( ! spaces on ! l9e e f & f g z a c5t] sweep ! circle j1 :i* del9eates ! out] surface ( our cyl9d] %ell4 ,let u n[1 z we direct$ 9 our =m] in/ructions1 draw a flatt5$ curve to repres5t ! act+ surface ( ! entrance lip ( our cyl9d] z if x 7 9 direct contact ) ! impulse face ( ! too?4 ,to del9eate ! exit lip we draw f ! c5t] g1 ,fig4 #acd1 to ! radial l9e g k1 said l9e pass+ ?r\gh ! po9t ( contact betwe5 ! too? & entrance lip ( ! cyl9d]4 ,let u next cont9ue ?is l9e on ! opposite side ( ! po9t g1 z %[n at g k'1 & we ?us bisect ! cyl9d] %ell into two equal p>ts ( #ahj degrees ea*4 ,z we previ\sly expla9$1 ! entire ext5t ( ! cyl9d] half %ell is #aif degrees4 ,we n[ set our divid]s to ! radius ( any conv5i5t arc :i* we h divid$ into degrees1 & f g z a c5t] sweep ! %ort arc l l1 & f ! int]section ( ?is arc ) ! l9e g k' we lay (f sixte5 degrees on ! said arc l & e/abli% ! po9t n1 f g z a c5t] draw ! radial l9e g n'4 ,take t5 degrees f ! same p>5t arc & e/abli% ! po9t m1 !n draw ! l9e g m'4 ,n[ ! arc on ! circles h j betwe5 ! l9es g n' & g m limits ! ext5t ( ! exit lip ( ! cyl9d] & ! arc betwe5 ! l9es g k' & g m' repres5ts ! lock+ surface ( ! cyl9d] %ell4 ,illu/ration3 ,fig4 #acd ,to del9eate ! ,u arms we ref] to ,fig4 #ace4 ,"h1 aga91 we draw ! arc a b c & del9eate a too? z be=e4 ,f ! po9t e locat$ at ! heel ( ! too? we draw ! radial l9e e e'4 ,f ! po9t e we lay (f on ! arc a five degrees & e/abli% ! po9t p2 we halve ?is space & draw ! %ort radial l9e p' s' & p s4 ,f ! po9t e on ! arc ,a we lay (f tw5ty-f\r degrees & e/abli% ! po9t t1 :i* locates ! heel ( ! next too? 9 advance ( ,a4 ,at two & a half degrees to ! "r ( ! po9t t we locate ! po9t r & draw ! %ort radial l9e r s4 ,on ! arc b & half way betwe5 ! l9es p s & r s1 we e/abli% ! po9t u1 & f x z a c5t] we sweep ! arc v def9+ ! curve ( ! ,u arms4 ,we h n[ giv5 m9ute in/ructions = draw+ a cyl9d] escapem5t 9 all its details except ! ext5t ( ! bank+ slot ( ! cyl9d]1 :i* is usually made to embrace an angul> ext5t ( #bgj degrees2 consequ5tly1 ! pill> ( ! cyl9d] w n measure m ?an n9ety degrees ( angul> ext5t4 ,!re is no escapem5t con/ruct$ :]e c>efully-made draw+s t5d m to p]fect k ( ! action ?an ! cyl9d]4 ,b x is necess>y ) ! pupil to in/itute a c>eful analysis ( ! actions involv$4 ,9 writ+ on a subject ( ?is k9d x is extremely p]plex+ to "k :5 to /op2 n t !re is s mu* dang] ( say+ too mu* z !re is n hav+ ! words read ) att5tion4 ,z an illu/ration1 let u consid] ! subject ( dep? betwe5 ! cyl9d] & ! escape :eel4 ,z previ\sly /at$1 #aif degrees ( cyl9d] %ell %\ld be employ$2 b suppose we f9d a wat* 9 :i* ! half %ell has _h too mu* cut away1 s ! too? on ent]+ ! half %ell aft] p>t+ ) ! entrance lip does n /rike dead on ! inside ( ! %ell1 b enc\nt]s ! edge ( ! exit lip4 ,9 ?is case ! impulse ( ! balance w\ld cause ! too? to slightly retrograde & ! wat* w\ld g b w\ld lack a good motion4 ,9 su* an in/ance a v slight advance ( ! *>iot w\ld rem$y ! fault--n p]fectly rem$y x1 b pat* up1 s to speak--& ! wat* w\ld run4 ,illu/ration3 ,fig4 #ace ,9 ?is day1 f9e cyl9d] wat*es are n made1 & only ! common k9d are met )1 & = ?is reason ! /ud5t %\ld famili>ize himself ) all ! imag9>y faults :i* c\ld occur f bad con/ruction4 ,! be/ way to d ?is is to del9eate :at he 7! /ud5t7 kn[s to be a faulty escapem5t1 z1 = in/ance1 a cyl9d] 9 :i* too mu* ( ! half %ell is cut away2 b 9 e in/ance let ! too? be ( ! correct =m4 ,!n del9eate an escapem5t 9 :i* ! cyl9d] is correct b ! tee? faulty2 also *ange ! ?ickness ( ! cyl9d] %ell1 s z to make ! tee? too %ort4 ,?is sort ( practice makes ! pupil ?9k & /udy & he w acquire a k :i* w nev] be =gott51 b always be pres5t to aid him 9 ! puzzles to :i* ! practical wat*mak] is e day subject4 ,! ability to solve ^! p]plex+ problems det]m9es 9 a great degree ! wor? ( a man to 8 employ]1 9 addition to e/abli%+ 8 reputation z a skill$ workman4 ,! "q is frequ5tly ask$1 ,h[ c ,i pr(itably employ myself 9 sp>e "t8 ,x w\ld seem t a wat*mak] c\ld d no bett] ?an to c>efully /udy matt]s horological1 /riv+ con/antly to atta9 a great] degree ( p]fection1 = by s do+ 8 e>n+ capacity w und\bt$ly be increas$4 ,,*apt] ,,iii4 ,,! ,,*ronomet] ,,escapem5t4 ,und\bt$ly ! det5t1 or1 z x is usually t]m$1 ! *ronomet] escapem5t1 is ! mo/ p]fect ( any ( our portable "t measur]s4 ,al?\gh ! m>9e *ronomet] is 9 a s5se a portable timepiece1 /ill x is n1 l a pocket wat*1 capable ( be+ adju/$ to positions4 ,z we are all aw>e1 ! det5t escapem5t is us$ 9 f9e pocket wat*es1 /ill ! g5]al feel+ ( manufactur]s is n favorable to x4 ,mu* ( ?is feel+ no d\bt is ow+ to ! me*anical difficulties pres5t$ 9 repair+ ! *ronomet] escapem5ts :5 ! det5t is brok51 & ! fact t ! spr+ det5t c\ld n be adju/$ to position4 ,we %all h occasion to speak ( position adju/m5ts z relate to ! *ronomet] escapem5t lat] on4 ,,advantages ,,( ,,! ,,*ronomet]4 ,we w proce$ n[ to consid] briefly ! advantages ! det5t escapem5t has ov] all o!rs4 ,x 0 soon discov]$ 9 con/ruct+ portable timepieces1 t to obta9 ! be/ results ! vibrations ( ! balance %\ld be z free z possible f any control or influ5ce except at su* times z x receiv$ ! necess>y impulse to ma9ta9 ! vibrations at a con/ant arc4 ,?is want und\bt$ly l$ to ! inv5tion ( ! det5t escapem5t4 ,! e>ly escapem5ts 7 all frictional escapem5ts1 i4e41 ! balance /aff 0 nev] free f ! influ5ce ( ! tra94 ,! v]ge escapem5t1 :i* 0 und\bt$ly ! fir/ employ$1 0 con/antly 9 contact ) ! escape :eel1 & 0 :at is kn[n z a recoil+ beat1 t is1 ! contact ( ! pallets actually caus$ ! escape :eel to recoil or turn back4 ,su* escapem5ts 7 too mu* influ5c$ by ! tra91 & any increase 9 p[] caus$ ! timepiece to ga94 ,! fir/ attempt to correct ?is imp]fection l$ to ! inv5tion & introduction ( ! fusee1 :i* enabl$ ! wat*mak] to obta9 f a coil$ spr+ ne>ly equal p[] dur+ ! entire p]iod ( action4 ,! next /ep 9 advance 0 ! dead-beat escapem5t1 :i* includ$ ! cyl9d] & duplex4 ,9 ^! frictional escapem5ts ! balance /aff lock$ ! tra9 :ile ! balance p]=m$ its arc ( vibration4 ,,frictional ,,escapem5ts ,,9 ,,high ,,favor4 ,^! frictional escapem5ts held favor ) _m em95t wat*mak]s ev5 aft] ! introduction ( ! deta*$ escapem5ts4 ,x is no m ?an natural we %\ld inquire1 :y8 ,! idea ) ! advocates ( ! frictional re/ escapem5ts 01 ! friction ( ! too? act$ z a corrective1 & l$ no d\bt to ! introduction ( go+-b>rel wat*es4 ,to illu/rate1 suppose 9 a cyl9d] wat* we increase ! motive p[]1 su* increase ( p[] w\ld n1 z 9 ! v]ge escapem5t1 increase ! rapidity ( ! vibrations2 x might1 9 fact1 cause ! timepiece to run sl[] f ! increas$ friction ( ! escape-:eel too? on ! cyl9d]2 also1 9 ! duplex escapem5t ! friction ( ! lock+ too? on ! /aff ret>ds ! vibrations4 ,dr4 ,hooke1 ! inv5tor ( ! balance spr+1 soon discov]$ x c\ld be manipulat$ to iso*ronism1 i4e41 s arcs ( diff]5t ext5t w\ld be =m$ 9 equal "t4 ,( c\rse1 ! friction-re/ escapem5t requir+ a spr+ to possess diff]5t prop]ties f "o :i* w\ld be iso*ronal ) a p]fectly deta*$ escapem5t1 ^! two frictional escapem5ts also diff]+1 ! duplex requir+ o!r prop]ties f :at w\ld iso*ronize a spr+ = a cyl9d] escapem5t4 ,al?\gh pocket wat*es ) duplex & cyl9d] escapem5ts hav+ balances comp5sat$ = heat & cold & balance spr+s adju/$ to iso*ronism gave v good results1 c>eful mak]s 7 satisfi$ t an escapem5t 9 :i* ! balance 0 deta*$ & free to act dur+ ! great] proportion ( ! arc ( vibration & uncontroll$ by any cause1 w\ld d /ill bett]1 & ?is l$ to ! det5t escapem5t4 ,,faults ,,9 ,,! ,,det5t ,,escapem5t4 ,z /at$ previ\sly1 ! det5t escapem5t hav+ pron\nc$ faults 9 positions :i* held x back1 x is probable x w\ld nev] h be5 employ$ 9 pocket wat*es to any ext5t if x _h n acquir$ su* a high reputation 9 m>9e *ronomet]s4 ,let u n[ analyze ! influ5ces :i* surr\nd ! det5t escapem5t 9 a m>9e *ronomet] & take acc\nt ( ! causes :i* are comb9$ to make x an accurate "t measur]1 & also take cognizance ( o!r int]f]+ causes :i* h a t5d5cy to prev5t desir$ results4 ,fir/1 we w imag9e a balance ) its spr+ su* z we f9d 9 f9e m>9e *ronomet]s4 ,x has small pivots runn+ 9 highly-poli%$ jewels2 su* pivots are p]fectly cyl9drical1 & no l>g] ?an are absolutely necess>y to endure ! task impos$ ^u !m--( c>ry+ ! weight ( ! balance & endure c>eful h&l+4 ,to af=d ! necess>y vibrations a spr+ is fitt$1 usually ( a helical =m1 s dispos$ z to cause ! balance to vibrate 9 arcs back & =? 9 equal "t1 provid$ ^! arcs are ( equal ext5t4 ,x is n[ to be tak5 note ( t we h x at our disposal & option to make ^! arcs equal 9 "t duration1 i4e41 to make ! long or %ort arcs ! quicke/ or to syn*ronize !m4 ,we c readily compreh5d we h n[ e/abli%$ a v p]fect measure ( %ort int]vals ( "t4 ,we c also see if we provide ! means ( ma9ta9+ ^! vibrations & c\nt+ !m we %\ld possess ! means ( c\nt+ ! flights ( "t ) great accuracy4 ,! conditions :i* surr\nd our balance are v con/ant1 ! small pivots turn+ 9 f9e h>d jewels lubricat$ ) an oil on :i* exposure to ! action ( ! air has little effect1 leaves b few influ5ces :i* c int]f]e ) ! regul> action ( our balance4 ,we add to ! influ5ces an adju/able correction = ! di/urbances ( heat & cold1 & we are conv9c$ t b little c\ld be add$4 ,,antagoni/ic ,,influ5ces4 ,9 ?is comb9ation we h pitt$ two antagoni/ic =ces aga9/ ea* o!r1 viz41 ! ela/icity ( ! spr+ & ! weight & in]tia ( ! balance2 bo? =ces are !oretically con/ant & %\ld produce con/ant results4 ,! me*anical "p ( ! problem is simply to af=d ^! two =ces p]fect facilities to act on ea* o!r & compel ea* to realize its full effect4 ,we mu/ also devise me*anical means to record ! duration ( ea* conflict1 t is1 ! "t l5g? ( ea* vibration4 ,_m ye>s h be5 sp5t 9 exp]im5t+ to arrive at ! be/ propositions to employ = ! sev]al p>ts to obta9 ! be/ practical results4 ,consequ5tly1 9 design+ a *ronomet] escapem5t we mu/ n only draw ! p>ts to a c]ta9 =m1 b consid] ! quality & weight ( mat]ial to employ4 ,to illu/rate :at we h j said1 suppose1 9 draw+ an escape :eel1 we mu/ n only del9eate ! prop] angle = ! act+ face ( ! too?1 b mu/ also take cognizance ( ! ?ickness ( ! too?4 ,by ?ickness we mean ! measurem5t ( ext5t ( ! too? 9 ! direction ( ! axis ( ! escape :eel4 ,an escape-:eel too? might be ( ! be/ =m to act 9 convey+ p[] to ! balance & yet by be+ too ?9 soon we> or produce excessive friction4 ,h[ ?ick an escape :eel %\ld be to produce be/ results1 is "o ( ! _m matt]s settl$ only by actual work%op exp]i5ce4 ,,factors ,,t ,,mu/ ,,be ,,consid]$4 ,ev5 ?is exp]i5ce is 9 e in/ance modifi$ by o!r influ5ces4 ,to illu/rate3 ,let u suppose 9 ! ord9>y to-day m>9e *ronomet] ! escape-:eel tee? ex]t$ a giv5 av]age =ce1 :i* we set d[n z s _m gra9s4 ,n[1 if we %\ld employ o!r mat]ial ?an hamm]-h>d5$ brass = an escape :eel x w\ld modify ! ?ickness2 also1 if we %\ld decrease ! motive p[] & increase ! arc ( impulse4 ,or1 if we %\ld dim9i% ! ext5t ( ! impulse arc & add to ! motive =ce1 e *ange w\ld h a controll+ influ5ce4 ,9 ! designs we %all employ1 x is our purpose to foll[ su* proportions z h be5 adopt$ by our be/ mak]s1 9 all respects1 includ+ =m1 size & mat]ial4 ,we w\ld say1 h[ev]1 !re has be5 b little deviation ) our pr9cipal manufactur]s ( m>9e *ronomet]s = ! la/ tw5ty ye>s z reg>ds ! g5]al pr9ciple on :i* !y 7 con/ruct$1 ! *ief aim be+ to excel 9 ! p]fection ( ! sev]al p>ts & ! c>e tak5 9 ! sev]al adju/m5ts4 ,be=e we proce$ to take up ! details ( con/ruct+ a *ronomet] escapem5t we _h bett] ma/] ! names = ! sev]al p>ts4 ,we %[ at ,fig4 #acf a complete plan ( a *ronomet] escapem5t z if se5 f ! back1 :i* is 9 reality ! front or dial side ( ! top plate4 ,! *ronomet] escapem5t consi/s ( f\r *ief or pr9cipal p>ts1 viz43 ,! escape :eel1 a portion ( :i* is %[n at ,a2 ! impulse roll] ,b2 unlock+ or dis*>g+ roll] ,c1 & ! det5t ,d4 ,^! pr9cipal p>ts are made up ( sub-p>ts3 ?us1 ! escape :eel is compos$ ( arms1 tee?1 recess & collet1 ! recess be+ ! portion ( ! escape :eel sunk1 to enable u to get wide tee? actions on ! impulse pallet4 ,! collet is a brass bu% on :i* ! :eel is set to af=d bett] support to ! escape :eel ?an c\ld be obta9$ by ! ?9n$ :eel if driv5 directly on ! p9ion arbor4 ,! impulse roll] is compos$ ( a cyl9drical /eel collet ,b1 ! impulse pallet d 7"s call x ! impulse /one71 ! safety recess b b4 ,! diamet] ( ! impulse collet is usually "o-half t ( ! escape :eel4 ,?is impulse roll] is /ak$ directly on ! balance /aff1 & its p]fection ( position assur$ by re/+ aga9/ ! foot ( ! %\ld] to :i* ! balance is secur$4 ,?is w be und]/ood by inspect+ ,fig4 #acg1 :i* is a v]tical longitud9al section ( a *ronomet] balance /aff1 ! l[] side ( ! impulse roll] be+ cupp$ out at c ) a ball gr9d] & f9i%$ a ball poli%4 ,illu/ration3 ,fig4 #acf ,illu/ration3 ,fig4 #acg ,x w be se5 ! impulse roll] is /ak$ flat aga9/ ! hub ,e ( ! balance /aff4 ,! unlock+ roll]1 or1 z x is also call$1 ! dis*>g+ roll]1 ,c1 is usually ?9n] ?an ! impulse roll] & has a jewel simil> to ! impulse jewel a %[n at f4 ,?is roll] is fitt$ by friction to ! l[] "p ( ! balance /aff & = additional security has a pipe or %ort socket e :i* embraces ! balance /aff at g4 ,! pipe e is usually flatt5$ on opposite sides to admit ( employ+ a special wr5* = turn+ ! dis*>g+ roll] 9 adju/+ ! jewel = op5+ ! escapem5t at ! prop] in/ant to p]mit ! escape :eel to act on ! impulse jewel a4 ,! p>ts :i* g to make up ! det5t ,d consi/ ( ! det5t foot ,f1 ! det5t spr+ h1 ! det5t blade i1 ! jewel pipe j1 ! lock+ jewel 7or /one7 s1 ! horn ( ! det5t k1 ! gold spr+ 7also call$ ! auxili>y & lift+ spr+7 m4 ,?is lift+ or gold spr+ m %\ld be made z light & ?9 z possible & /& c>eful h&l+4 ,we _c impress on our read]s too mu* ! importance ( mak+ a *ronomet] det5t light4 ,v few det5ts1 ev5 f ! h&s ( our be/ mak]s1 are z light z !y might be4 ,we %\ld 9 su* con/ruction h v little c>e = clumsy workm5 :o may h to repair su* me*anism4 ,?is feature %\ld n ent] into consid]ation4 ,we %\ld only be influ5c$ by ! feel+ t we are work+ = be/ results1 & x is act+ "u ?is influ5ce t we devote s mu* "t to e/abli%+ a correct idea ( ! und]ly+ pr9ciples involv$ 9 a m>9e *ronomet]1 in/ead ( proce$+ directly to ! draw+ ( su* an escapem5t & give empirical rules = ! l5g? ( ?is or ! diamet] ( t4 ,z1 = in/ance1 9 f9i%+ ! det5t spr+ h1 suppose we read 9 text books ! spr+ %\ld be r$uc$ 9 ?ickness1 s t a weight ( "o p5nyweight susp5d$ f ! pipe j w deflect ! det5t 4 ,?is is a rule well en\gh = p employ$ 9 a *ronomet] factory1 b = ! horological /ud5t su* fix$ rules 7ev5 if rememb]$7 w\ld be ( small use4 ,:at ! /ud5t requires is s\nd k ( ! :ys1 9 ord] t he may be able to ?or\ghly ma/] ?is escapem5t4 ,,functions ,,( ,,! ,,det5t4 ,we c see1 aft] a brief analysis ( ! pr9ciples involv$1 t ! functions requir$ ( ! det5t ,d are to lock ! escape :eel ,a & hold x :ile ! balance p]=ms its excursion1 & t ! det5t or recov]+ spr+ h mu/ h suffici5t /r5g? & p[] to p]=m two functions3 7#a7 ,return ! lock+ /one s back to ! prop] position to arre/ & hold ! escape :eel2 7#b7 ! spr+ h mu/ also be able to resi/1 )\t buckl+ or cockl+1 ! ?ru/ ( ! escape :eel1 repres5t$ by ! arr[s p o4 ,n[ we c readily und]/& t ! light] we make ! p>ts i j k m1 ! weak] ! spr+ h c be4 ,y say1 p]haps1 if we make x too weak x w be liable to buckle "u ! pressure ( ! escape :eel2 ?is1 9 turn1 w dep5d 9 a great measure on ! condition ( ! spr+ h4 ,suppose we h x /raight :5 we put x 9 position1 x w !n h no /ress to keep x press$ to ! hold+1 /op or bank+ screw1 :i* regulates ! lock ( ! too?4 ,to obta9 ?is /ress we set ! foot ,f ( ! det5t ar\nd to ! position indicat$ by ! dott$ l9es r & n1 & we get ! prop] t5sion on ! det5t spr+ to effect ! lock1 or r ( ! det5t 9 "t to lock ! escape :eel2 b ! spr+ h1 in/ead ( be+ p]fectly /raight1 is b5t & consequ5tly n 9 a condition to /& ! ?ru/ ( ! escape :eel1 indicat$ by ! arr[s o p4 ,,obta9+ ,,! ,,be/ ,,conditions4 ,n[ ! true way to obta9 ! be/ conditions is to give ! spr+ h a set curvature be=e we put x 9 place1 & !n :5 ! det5t is 9 ! prop] position ! spr+ h w h t5sion en\gh on x to br+ ! jewel s aga9/ ! /op screw1 :i* regulates ! lock1 & /ill be p]fectly /raight4 ,?is matt] is ( s mu* importance t we w give fur!r explanation4 ,suppose we b5d ! det5t spr+ h s x is curv$ to ! dott$ l9e t1 ,fig4 #acf1 & !n ! foot ,f w\ld assume ! position indicat$ at ! dott$ l9e r4 ,we next imag9e ! foot ,f to be put 9 ! position %[n by ! full l9es1 ! spr+ h w become /raight aga9 & 9 p]fect %ape to resi/ ! ?ru/ ( ! escape :eel4 ,little ways & me?ods l ! above h long be5 kn[n to ! trade1 b = "s reason are nev] m5tion$ 9 our text books4 ,a det5t spr+ #b_/ajjj ?ick & #hj_/ajjj wide w /& ! ?ru/ = any well-con/ruct$ m>9e *ronomet] 9 exi/5ce1 & yet x w n require half a p5nyweight to deflect x "o-f\r? ( an in*4 ,x is a good rule to make ! l5g? ( ! det5t f ! foot ,f to ! c5t] ( ! lock+ jewel pipe j equal to ! diamet] ( ! escape :eel1 & ! l5g? ( ! det5t spr+ h two-sev5?s ( ?is di/ance4 ,! l5g? ( ! horn k is det]m9$ by ! graphic plan & c be tak5 f ! plott$ plan4 ,! end1 h[ev]1 %\ld approa* z ne> to ! dis*>g+ jewel z possible & n absolutely t\*4 ,! dis*>g+ 7gold7 spr+ m is atta*$ to ! blade i ( ! det5t ) a small screw l cut 9 a ,no4 #ah hole ( a ,swiss plate4 ,:ile !re %\ld be a slight increase 9 ?ickness 9 ! det5t blade at w1 :]e ! gold spr+ is atta*$1 /ill x %\ld be no m ?an to sep>ate ! gold spr+ m f ! det5t blade i4 ,,important ,,consid]ations4 ,x is important ! spr+ %\ld be absolutely free & n t\* ! det5t except at its po9t ( atta*m5t at w & to re/ aga9/ ! end ( ! horn k1 & ! extreme end ( k1 :]e ! gold spr+ re/s1 %\ld only be :at we may t]m a dull or ?ick edge4 ,! end ( ! horn k 7%[n at y7 is be/ made1 = conv5i5ce ( elegant con/ruction1 squ>e--t is1 ! "p y turns at "r angles to k & is made ?ick] ?an k & at ! same "t deep]2 or1 to make a comp>ison to a clumsy article1 y is l ! head ( a nail1 :i* is all on "o side4 ,"s mak]s b5d ! horn k to a curve & all[ ! end ( ! horn to arre/ or /op ! gold spr+2 b z x is important ! entire det5t %\ld be z light z possible1 ! squ>e end be/ answ]s ?is purpose4 ,! bank+ plac$ at j %\ld arre/ ! det5t z ?r[n back by ! spr+ h at ! po9t ( p]cussion4 ,?is po9t ( p]cussion is a c]ta9 po9t 9 a mov+ mass :]e ! greate/ ef=t is produc$ & w\ld be some:]e ne> ! po9t x1 9 a b> ,g turn+ on a pivot at z1 ,fig4 #ach4 ,x w be evid5t1 on inspection ( ?is figure1 if ! b> ,g 0 turn+ on ! c5t] z x w\ld n give ! h>de/ impact at ! end v1 z p>ts ( its =ce w\ld be exp5d$ at ! c5t] z4 ,illu/ration3 ,fig4 #ach ,,decisions ,,arriv$ ,,at ,,by ,,exp]i5ce4 ,exp]i5ce has decid$ t ! impulse roll] %\ld be ab\t half ! diamet] ( ! escape :eel1 & exp]i5ce has also decid$ t an escape :eel ( fifte5 tee? has ! greate/ numb] ( advantages2 also1 t ! balance %\ld make #ad1djj vibrations 9 "o h\r4 ,we w accept ^! proportions & conditions z be/1 f ! fact t !y are n[ almo/ univ]sally adopt$ by our be/ *ronomet] mak]s4 ,al?\gh x w\ld seem z if ^! proportions %\ld h e/abli%$ !mselves e>li] among practical m51 we %all 9 ^! draw+s conf9e ourselves to ! graphic plan1 consid]+ x pref]able4 ,9 ! practical detail draw+ we advise ! employm5t ( ! scale giv51 i4e41 del9eat+ an escape :eel #aj 9 diamet]4 ,! draw+s :i* accompany ! description are "o-f\r? ( ?is size1 = ! sake ( conv5i5ce 9 copy+4 ,) an escape :eel ( fifte5 tee? ! impulse arc is exactly tw5ty-f\r degrees1 & ( c\rse ! p]iph]y ( ! impulse roll] mu/ int]sect ! p]iph]y ( ! escape :eel = ?is arc 7#bd74 ,! circles ,a ,b1 ,fig4 #aci1 repres5t ! p]iph]ies ( ^! two mobiles1 & ! problem 9 h& is to locate & def9e ! position ( ! two c5t]s a c4 ,^!1 ( c\rse1 are n sep>at$1 ! sum ( ! two radii1 i4e41 #e #b 79 ! l>ge draw+71 z ^! circles int]sect1 z %[n at d4 ,ari?metically consid]$1 ! problem is q difficult1 b graphically1 simple en\gh4 ,aft] we h swept ! circle ,a ) a radius ( #e1 we draw ! radial l9e a f1 said l9e ext5d+ beyond ! circle ,a4 ,,locat+ ,,! ,,c5t] ,,( ,,! ,,balance ,,/aff4 ,some:]e on ?is l9e is locat$ ! c5t] ( ! balance /aff1 & x is ! problem 9 h& to locate or e/abli% ?is c5t]4 ,n[1 x is kn[n ! circles :i* def9e ! p]iph]ies ( ! escape :eel & ! impulse roll] int]sect at e e#b4 ,we c e/abli% on our circle ,a :]e ^! int]sections take place by lay+ (f twelve degrees1 "o-half ( ! impulse arc on ea* side ( ! l9e ( c5t]s a f on ?is circle & e/abli%+ ! po9ts e e#b4 ,^! po9ts e e#b be+ locat$ at ! int]section ( ! circles ,a & ,b1 mu/ be at ! respective di/ances ( #e & #b di/ance f ! c5t] ( ! circles ,a ,b2 consequ5tly1 if we set our divid]s at #b & place "o leg at e & sweep ! %ort arc g#b1 & repeat ?is process :5 "o leg ( ! divid]s is set at e#b1 ! int]section ( ! %ort arcs g & g#b w locate ! c5t] ( our balance /aff4 ,we h n[ our two c5t]s e/abli%$1 ^: p]iph]ies are 9 ! relation ( #b to #a4 ,to "k1 9 ! *ronomet] :i* we are suppos$ to be con/ruct+1 ! exact di/ance ap>t at :i* to plant ! hole jewels = our two mobiles1 i4e41 escape :eel & balance /aff1 we measure c>efully on our draw+ ! di/ance f a to c 7! latt] we hav+ j e/abli%$7 & make our /atem5t 9 ! rule ( ?ree1 z foll[s3 ,z 7#aj7 ! diamet] ( drawn escape :eel is to our real escape :eel s is ! measur$ di/ance on our draw+ to ! real di/ance 9 ! *ronomet] we are con/ruct+4 ,x is well to use great c>e 9 ! l>ge draw+ to obta9 great accuracy1 & make said l>ge draw+ on a %eet ( metal4 ,?is c\rse is ju/ifi$ by ! degree ( p]fection to :i* measur+ tools h arriv$ 9 ?is day4 ,x w be f\nd on measurem5t ( ! arc ( ! circle ,b1 embrac$ betwe5 ! int]sections e e#b1 t x is ab\t =ty-eight degrees4 ,h[ mu* ( ?is we c utilize 9 our escapem5t w dep5d v mu* on ! p]fection & accuracy ( con/ruction4 ,illu/ration3 ,fig4 #aci ,we %[ at ,fig4 #adj ?ree tee? ( an escape :eel1 toge!r ) ! lock+ jewel ,e & impulse jewel ,d4 ,n[1 :ile !oretically we c\ld comm5ce ! impulse z soon z ! impulse jewel ,d 0 inside ( ! circle repres5t+ ! p]iph]y ( ! escape :eel1 /ill1 9 practical con/ruction1 we mu/ all[ = cont+5cies4 ,be=e x is safe = ! escape :eel to attack ! impulse jewel1 said jewel mu/ be safely inside ( said escape :eel p]iph]y1 9 ord] t ! attack+ too? %all act ) c]ta9ty & its full effect4 ,a good deal ( ?\ght & /udy c be be/[$ to great advantage on ! action ( a *ronomet] escapem5t4 ,let u exam9e ! conditions involv$4 ,we %[ 9 ,fig4 #adj ! impulse jewel ,d j pass+ inside ! circle ( ! p]iph]y ( ! escape :eel4 ,n[ ! att5dant conditions are ^!3 ,! escape :eel is lock$ fa/ & p]fectly dead1 & 9 ! ef=t ( unlock+ x has to fir/ turn backw>d aga9/ ! ef=t ( ! ma9spr+2 ! p[] ( =ce requir$ = ?is ef=t is d]iv$ f ! balance 9 :i* is /or$ up1 s to speak1 p[] f impulses imp>t$ to ! balance by =m] ef=ts ( ! escape :eel4 ,9 actual fact1 ! balance at ! "t ! unlock+ takes place is mov+ ) ne>ly its greate/ p]iph]al velocity &1 z /at$ above1 ! escape :eel is at re/4 ,"h comes a v delicate problem z reg>ds sett+ ! unlock+ or dis*>g+ jewel4 ,let u fir/ suppose we set ! dis*>g+ jewel s ! lock+ jewel frees its too? at ! exact in/ant ! impulse jewel is inside ! p]iph]y ( ! escape :eel4 ,z j /at$1 ! escape :eel is n only dead b actually mov+ back at ! "t ! release takes place4 ,n[1 x is evid5t t ! escape :eel requires an appreciable "t to move =w>d & attack ! impulse jewel1 & dur+ ?is appreciable "t ! impulse jewel has be5 mov+ =w>d inside ( ! arc ,a ,a1 :i* repres5ts ! p]iph]y ( ! escape :eel4 ,! prop] consid]ation ( ?is problem is ( m importance 9 *ronomet] mak+ ?an we might at fir/ ?\ght h imag9$1 consequ5tly1 we %all dwell ^u x at "s l5g?4 ,,h[ ,,to ,,set ,,! ,,dis*>g+ ,,jewel4 ,illu/ration3 ,fig4 #adj ,!oretically1 ! escape-:eel too? %\ld enc\nt] ! impulse jewel at ! "t--in/ant--bo? are mov+ ) ! same velocity4 ,x is evid5t !n t !re c be no special rule giv5 = ?is1 i4e41 h[ to set ! dis*>g+ jewel s x w free ! too? at exactly ! prop] in/ant1 f ! fact t "o *ronomet] tra9 may be mu* sl[] 9 gett+ to move =w>d f said tra9 be+ heavy & clumsy 9 con/ruction4 ,let u make an exp]im5t ) a real *ronomet] 9 illu/ration ( our problem4 ,to d s we remove our balance spr+ & place ! balance 9 position4 ,if we />t ! balance revolv+ 9 ! direction ( ! arr[ y1 ,fig4 #adj1 x w cause ! escapem5t to be unlock$ & ! balance to turn rapidly 9 "o direction & ) increas+ velocity until1 9 fact1 ! escape :eel has b v little effect on ! impulse jewel2 9 fact1 we c\ld1 by apply+ "s outside s\rce ( p[]--l bl[+ ) a bl[ pipe on ! balance--cause ! impulse jewel to pass 9 advance ( ! escape :eel2 t is1 ! escape-:eel too? w\ld n be able to cat* ! impulse jewel dur+ ! entire impulse arc4 ,let u suppose1 n[1 we set our unlock+ or dis*>g+ jewel 9 advance1 t is1 s ! escapem5t is really unlock$ a little be=e ! sett+ p>ts are 9 ! positions & relations %[n 9 ,fig4 #ada4 ,"u ! new conditions ! escape :eel w\ld comm5ce to move & get suffici5t velocity on x to act on ! impulse jewel z soon z x 0 inside ( ! p]iph]y ( ! escape :eel4 ,if ! balance 0 turn$ sl[ly n[ ! too? ( ! escape :eel w\ld n enc\nt] ! impulse jewel at all1 b fall into ! pass+ holl[ n2 b if we give ! balance a high velocity1 ! too? w\ld aga9 enc\nt] & act ^u ! jewel 9 ! prop] mann]4 ,exp]i5c$ adju/]s ( *ronomet]s c tell by li/5+ if ! escape-:eel too? attacks ! impulse jewel prop]ly1 i4e41 :5 bo? are mov+ ) simil> velocities4 ,! true s\nd indicat+ correct action is only giv5 :5 ! balance has its maximum arc ( vibration1 :i* %\ld be ab\t #a revolutions1 or p]=m an arc ( #bbe degrees on ea* excursion4 ,fig4 #adb is a side view ( ,fig4 #ada se5 9 ! direction ( ! arr[ y4 ,we h m5tion$ a *>iot to :i* ! det5t is atta*$1 b we %all make no attempt to %[ x 9 ! accompany+ draw+s1 z x really has no relation to ! problem 9 h&2 i4e41 expla9+ ! action ( ! *ronomet] escapem5t1 z ! *>iot relates entirely to ! conv5i5ce ( sett+ & adju/+ ! relation ( ! second p>ts4 ,! size1 or bett]1 say1 ! inside diamet] ( ! pipe at ,c1 ,fig4 #adc1 :i* holds ! lock+ jewel1 %\ld be ab\t "o-?ird ( a too? space1 & ! jewel made to fit p]fectly4 ,usually1 jewelmak]s h a t5d5cy to make ?is jewel too frail1 cutt+ away ! jewel back ( ! releas+ angle 7n1 ,fig4 #adc7 too mu*4 ,a ,,good ,,=m ,,( ,,lock+ ,,/one4 ,a v practical =m = a lock+ /one is %[n 9 transv]se section at ,fig4 #adc4 ,9 con/ruction x is a piece ( ruby1 or1 bett]1 sapphire cut to co9cide to its axis ( cry/allization1 into fir/ a solid cyl9d] nicely fitt+ ! pipe ,c & f9i%$ ) an aft]-gr9d+1 cutt+ away f\r-t5?s ( ! cyl9d]1 z %[n at ,i1 ,fig4 #adc4 ,"h ! l9e m repres5ts ! lock+ face ( ! jewel & ! l9e o ! cle>ance to free ! escap+ too?1 ! angle at n be+ ab\t fifty-f\r degrees4 ,?is angle 7n7 %\ld leave ! r\nd+ ( ! /one intact1 t is1 ! r\nd+ ( ! angle %\ld be left & n made aft] ! flat faces m o are gr\nd & poli%$4 ,! circul> space at ,i is fill$ ) an alum9um p94 ,! sizes %[n are ( ab\t ! "r relative proportions2 b we feel x well to repeat ! /atem5t made previ\sly1 to ! effect t ! det5t to a *ronomet] _c well be made too light4 ,illu/ration3 ,fig4 #ada ,illu/ration3 ,fig4 #adb ,illu/ration3 ,fig4 #adc ,! s-call$ gold spr+ %[n at ,h1 ,figs4 #ada & #adb1 %\ld also be z light z is consi/5t ) due /r5g? & c be made ( ! composite metal us$ = gold fill$ goods1 z ! only real b5efit to be d]iv$ f employ+ gold is to avoid ! necessity ( apply+ oil to any "p ( ! escapem5t4 ,if su* gold metal is employ$1 aft] hamm]+ to obta9 ! greate/ possible ela/icity to ! spr+1 ! gold is fil$ away1 except :]e ! spr+ is act$ ^u by ! dis*>g+ jewel h4 ,we h previ\sly m5tion$ ! importance ( avoid+ wide1 flat contacts betwe5 all act+ surfaces1 l :]e ! gold spr+ re/s on ! horn ( ! det5t at p2 also :]e ! det5t banks on ! bank+ screw1 %[n at ,g1 ,fig4 #adb4 ,"u ?is pr9ciple ! impact ( ! face ( ! dis*>g+ jewel ) ! end ( ! gold spr+ %\ld be conf9$ to z small a surface z is consi/5t ) :at w n produce abrasive action4 ,! gold spr+ is %ap$ z %[n at ,fig4 #adb & loses1 9 a measure1 "u ! pipe ( ! lock+ jewel1 a little m ?an "o-half ( ! pipe bel[ ! blade ( ! det5t be+ cut away1 z %[n 9 ,fig4 #adc1 :]e ! l9es r r %[ ! ext5t ( ! "p ( ! pipe :i* banks aga9/ ! bank+ screw ,g4 ,9 ?is place ev51 only ! curv$ surface ( ! outside ( ! pipe t\*es ! screw ,g1 aga9 avoid+ contact ( broad surfaces4 ,we %[ ! gold spr+ sep>ate at ,fig4 #add4 ,a slight torsion or twi/ is giv5 to ! gold spr+ to cause x to b5d ) a true curvature 9 ! act ( all[+ ! dis*>g+ pallet to pass back aft] unlock+4 ,if ! gold spr+ is fil$ & /on$ to ! "r flexure1 t is1 ! ?9ne/ po9t prop]ly plac$ or1 say1 locat$1 ! gold spr+ w n cont9ue 9 contact ) ! dis*>g+ pallet any long] "t or ?r\gh a great] arc ?an dur+ ! process ( unlock+4 ,to make ?is /atem5t bett] und]/ood1 let u suppose ! weake/ "p ( ! gold spr+ ,h is opposite ! arr[ y1 ,fig4 #ada1 x w readily be und]/ood ! contact ( ! dis*>g+ /one h w\ld cont9ue long] ?an if ! po9t ( greate/ 7or easie/7 flexure 0 ne>] to ! pipe ,c4 ,if ! end ,d#b ( ! horn ( ! det5t is z ne> z x %\ld be to ! dis*>g+ /one !re ne$ be no fe> b ! escapem5t w be unlock$4 ,! horn ,d#b ( ! det5t %\ld be b5t until five degrees ( angul> motion ( ! balance w unlock ! escape1 & ! contact ( dis*>g+ jewel h %\ld be made )\t engag+ friction4 ,?is condition c be det]m9$ by obs]v+ if ! jewel seems to slide up 7t[>d ! pipe ,c7 on ! gold spr+ aft] contact4 ,"s adju/]s set ! jewel ,j1 ,figs4 #adc & #ada1 9 su* a way t ! too? re/s close to ! base2 su* adju/]s claim+ ?is c\rse has a t5d5cy to avoid cockl+ or buckl+ ( ! det5t spr+ ,e4 ,su* adju/]s also set ! impulse jewel slightly oblique1 s z to lean on ! opposite angle ( ! too?4 ,our advice is to set bo? /ones 9 places correspond+ to ! axis ( ! balance /aff1 & ! escape-:eel mobiles4 ,,! ,,det5t ,,spr+4 ,illu/ration3 ,fig4 #add ,x w be notic$ we h made ! det5t spr+ ,e pretty wide & ext5d$ x well above ! blade ( ! det5t4 ,by %ap+ ! det5t 9 ?is way ne>ly all ! t5d5cy ( ! spr+ ,e to cockle is annull$4 ,we w\ld beg to add to :at we said 9 reg>d to sett+ jewels obliquely4 ,we are unable to und]/& ! advantage ( wide-fac$ /ones & deep tee? :5 we d n take advantage ( ! wide surfaces :i* we ass]t are important4 ,we gu>antee t ) a det5t & spr+ made z we %[1 !re w be no t5d5cy to cockle1 or if !re is1 x w be too feeble to ev5 display itself4 ,^? :o h _h ext5d$ exp]i5ce ) *ronomet]s _c fail to h notic$ a gummy secretion :i* accumulates on ! impulse & dis*>g+ /ones ( a *ronomet]1 al?\gh no oil is ev] appli$ to !m4 ,we imag9e ?is coat+ is d]iv$ f ! oil appli$ to ! pivots1 :i* c]ta9ly evaporates1 passes into vapor1 or ! rema9+ oil c\ld n become gummy4 ,we w\ld advise1 :5 sett+ jewels 7we mean ! lock+1 impulse & dis*>g+ jewels71 to employ no m %ellac ?an is absolutely necess>y1 dep5d+ *iefly on metallic contact = security4 ,,details ,,( ,,con/ruction4 ,we w n[ say a few words ab\t ! numb] ( beats to ! h\r = a box or m>9e *ronomet] to make to give ! be/ results4 ,exp]i5ce %[s t sl[ b mo/ p]fect con/ruction has settl$ t #ad1djj1 or f\r vibrations ( ! balance to a second1 z ! prop] numb]1 ! weight ( balance1 includ+ balance prop] & movable weights1 to be ab\t #e p5nyweights1 & ! comp5sat+ curb ab\t #a-b_/aj 9 diamet]4 ,! escape :eel1 #ee_/ajj 9 diamet] & recess$ s z to be z light z possible1 %\ld h suffici5t /r5g? to p]=m its functions prop]ly4 ,! ?ickness or1 m prop]ly1 ! face ext5t ( ! too?1 measur$ 9 ! direction ( ! axis ( ! escape :eel1 %\ld be ab\t #a_/bj4 ,! recess+ %\ld ext5d half way up ! radial back ( ! too? at t4 ,! curvature ( ! back ( ! tee? is produc$ ) ! same radii z ! impulse roll]4 ,to locate ! c5t] f :i* ! arc :i* def9es ! back ( ! tee? is swept1 we halve ! space betwe5 ! tee? ,a#b & a#d & e/abli% ! po9t n1 ,fig4 #ada1 & ) our divid]s set to sweep ! circle repres5t+ ! impulse roll]1 we sweep an arc pass+ ! po9t ( ! too? ,a#c & u1 ?us locat+ ! c5t] w4 ,f ! c5t] k ( ! escape :eel we sweep a complete circle1 a portion ( :i* is repres5t$ by ! arc w v4 ,= del9eat+ o!r tee? we set "o leg ( our divid]s to agree ) ! po9t ( ! too? & ! o!r leg on ! circle w v & produce an arc l z u4 ,,orig9al ,,design+ ,,( ,,! ,,escapem5t4 ,on del9eat+ our *ronomet] escapem5t %[n at ,fig4 #ada we h foll[$ no text-book au?ority1 b h drawn x accord+ to su* requirem5ts z are ess5tial to obta9 ! be/ results4 ,an escapem5t ( any k9d is only a ma*9e1 & m]ely requires 9 its con/ruction a comb9ation ( s\nd me*anical pr9ciples4 ,nei!r ,sauni] nor ,britt51 9 _! works1 give in/ructions = draw+ ?is escapem5t :i* w be> close analysis4 ,x is n our int5tion1 h[ev]1 to criticise ^! au?ors1 except we c pres5t bett] me?ods & give correct sy/ems4 ,,tang5tial ,,lock+s4 ,x has be5 a matt] ( great cont5tion ) mak]s ( *ronomet] & also lev] escapem5ts z to ! advantages ( tang5tial lock+s4 ,by ?is t]m is meant a lock+ ! same z is %[n at ,c1 ,fig4 #ada1 & means a det5t plant$ at "r angles to a l9e radial to ! escape-:eel axis1 said radial l9e pass+ ?r\gh ! po9t ( ! escape-:eel too? re/+ on ! lock+ jewel4 ,9 escapem5ts n set tang5tial1 ! det5t is pu%$ =w>d 9 ! direction ( ! arr[ x ab\t half a too? space4 ,britt51 9 8 ,h&-,book1 gives a draw+ ( su* an escapem5t4 ,we claim ! *ief advantage ( tang5tial lock+ to lie 9 ! action ( ! escape-:eel tee?1 bo? on ! impulse /one & also on ! lock+ /one ( ! det5t4 ,sauni]1 9 8 ,mod]n ,horology1 gives ! incl9ation ( ! front fan ( ! escape-:eel tee? z be+ at an angle ( tw5ty-sev5 degrees to a radial l9e4 ,britt5 says tw5ty degrees1 & also employs a non-tang5tial lock+4 ,our draw+ is on an angle ( tw5ty-eight degrees1 :i* is z l[ z is safe1 z we %all proce$ to demon/rate4 ,= e/abli%+ ! angle ( an escape-:eel too? we draw ! l9e ,c d1 f ! po9t ( ! escape-:eel too? re/+ on ! lock+ /one %[n at ,c at an angle ( tw5ty-eight degrees to radial l9e ,c k4 ,we h already discuss$ h[ to locate & plant ! c5t] ( ! balance /aff4 ,we %all n %[ 9 ?is draw+ ! angul> motion ( ! escape :eel1 b del9eate at ! radial l9es c e & c f ( ! arc ( ! balance dur+ ! ext5t ( its implication ) ! p]iph]y ( ! escape :eel1 :i* arc is "o ( ab\t =ty-eight degrees4 ,( ?is angle b =ty-?ree degrees is attempt$ to be utiliz$ = ! purpose ( impulse1 five degrees be+ all[$ = ! impulse jewel to pass inside ( ! arc ( p]iph]y ( ! escape :eel be=e ! lock+ jewel releases ! too? ( ! escape :eel re/+ ^u x4 ,at ?is po9t x is suppos$ ! escape :eel attacks ! impulse jewel1 because1 z we j expla9$1 ! lock+ jewel has releas$ ! too? engag+ x4 ,n[1 if ! tra9 _h no weight1 no in]tia to ov]come1 ! escape :eel too? ,a#b w\ld move =w>d & attack ! impulse pallet in/antly2 b1 9 fact1 z we h already expla9$1 !re w be an appreciable "t elapse be=e ! too? ov]takes ! rapidly-mov+ impulse jewel4 ,x w1 ( c\rse1 be und]/ood t ! ref]5ce lett]s us$ h]e9 ref] to ! illu/rations t h appe>$ on prec$+ pages4 ,if we reason c>efully on ! matt]1 we w readily compreh5d t we c move ! lock+ jewel1 i4e41 set x s ! unlock+ w take place 9 reality be=e ! impulse jewel has pass$ ?r\gh ! entire five degrees ( arc embrac$ betwe5 ! radial l9es c e & c g1 ,fig4 #ada1 & yet h ! too? attack ! jewel aft] ! five degrees ( arc4 ,9 practice x is safe to set ! dis*>g+ jewel h s ! release ( ! held too? ,a#a w take place z soon z ! too? ,a#b is inside ! pr9cipal l9e ( ! escape :eel4 ,z we previ\sly expla9$1 ! contact betwe5 ,a#b & ! impulse jewel i w\ld n 9 reality occur until ! said jewel i _h fully pass$ ?r\gh ! arc 7five degrees7 embrac$ betwe5 ! radial l9es c e & c g4 ,at ?is po9t we w expla9 :y we drew ! front fan ( ! escape-:eel tee? at ! angle ( tw5ty-eight degrees4 ,if ! fan ( impulse jewel i is set radial to ! axis ( ! balance1 ! engagem5t ( ! too? ,a#b w\ld be at a disadvantage if x took place prior to ?is jewel pass+ ?r\gh an arc ( five degrees inside ! p]iph]y ( ! escape :eel4 ,x w be evid5t on ?\ght t if an escape-:eel too? engag$ ! impulse /one be=e ! five-degrees angle _h pass$1 ! contact w\ld n be on its flat face1 b ! too? w\ld /rike ! impulse jewel on its out] angle4 ,a cont9u$ inspection w also reveal ! fact t 9 ord] to h ! po9t ( ! too? engage ! flat surface ( ! impulse pallet ! impulse jewel mu/ co9cide ) ! radial l9e c g4 ,if we seek to rem$y ?is condition by sett+ ! impulse jewel s ! face is n radial1 b incl9$ backw>d1 we enc\nt] a bad engag+ friction1 because1 dur+ ! fir/ "p ( ! impulse action1 ! too? has to slide up ! face ( ! impulse jewel4 ,all ?+s consid]$1 ! be/ action is obta9$ ) ! impulse jewel set s ! act+ face is radial to ! balance /aff & ! engagem5t takes place betwe5 ! too? & ! impulse jewel :5 bo? are mov+ ) equal velocities1 i4e41 :5 ! balance is p]=m+ ) an arc 7or motion7 ( #a revolutions or #bbe degrees ea* way f a po9t ( re/4 ,"u su* conditions ! actual contact w n take place be=e "s little "t aft] ! impulse jewel has pass$ ! five-degree arc betwe5 ! l9es c e & c g4 ,,! ,,drop ,,& ,,draw ,,consid]$4 ,exactly h[ mu* drop mu/ be all[$ f ! "t ! too? leaves ! impulse jewel be=e ! lock+ too? engages ! lock+ jewel w dep5d 9 a great measure on ! p]fection ( workman%ip1 b %\ld 9 no in/ance be m ?an :at is absolutely requir$ to make ! escapem5t safe4 ,! am\nt ( draw giv5 to ! lock+ /one c is usually ab\t twelve degrees to ! radial l9e k a4 ,mu* ( ! p]fection ( ! *ronomet] escapem5t w always dep5d on ! skill ( ! escapem5t adju/] & n on ! me*anical p]fection ( ! p>ts4 ,! jewels all h to be set by h& aft] !y are made1 & ! di/ance to :i* ! impulse jewel protrudes beyond ! p]iph]y ( ! impulse roll] is entirely a matt] = h& & eye1 b %\ld nev] exce$ #b_/ajjj4 ,aft] ! lock+ jewel c is set1 we c set ! foot ,f ( ! det5t ,d =w>d or back1 to p]fect & correct ! engagem5t ( ! escape-:eel tee? ) ! impulse roll] ,b4 ,if we set ?is too f> =w>d1 ! too? ,a#c w enc\nt] ! roll] :ile ! too? ,a#b w be free4 ,we w\ld beg to say "h !re is no escape :eel made :i* requires ! same extreme accuracy z ! *ronomet]1 z ! too? spaces & ! equal radial ext5t ( ea* too? %\ld be only limit$ by our p[]s t[>d p]fection4 ,x is usual to give ! det5t a lock+ ( ab\t two degrees2 t is1 x requires ab\t two degrees to op5 x1 c\nt+ ! c5t] ( fluxion ( ! det5t spr+ ,e & five degrees ( balance arc4 ,,fitt+ ,,up ,,( ,,! ,,foot4 ,sev]al attempts h be5 made by *ronomet] mak]s to h ! foot ,f adju/able2 t is1 s x c\ld be mov$ back & =? ) a screw1 b we h nev] kn[n ( any?+ satisfactory be+ accompli%$ 9 ?is direction4 ,ab\t ! be/ way ( fitt+ up ! foot ,f seems to be to provide x ) two s(t iron /eady p9s 7%[n at j7 ) correspond+ holes 9 ! *>iot1 said holes be+ conically enl>g$ s !y 7! p9s7 c be b5t & manipulat$ s ! det5t n only /&s 9 ! prop] position z reg>ds ! escape :eel1 b also to give ! det5t spr+ ,e ! prop] ela/ic =ce to return 9 "t to af=d a secure lock+ to ! arre/+ too? ( ! escape :eel aft] an impulse has be5 giv54 ,if ^! p9s j are b5t prop]ly by ! adju/]1 :oev] aft]w>ds cleans ! *ronomet] ne$s only to g5tly pu% ! foot ,f =w>d s z to cause ! p9s j to take ! correct positions z det]m9$ by ! adju/] & set ! screw l up to hold ! foot ,f :5 all ! o!r relations are z !y %\ld be1 except su* z we c control by ! screw ,g1 :i* prev5ts ! lock+ jewel f ent]+ too deeply into ! escape :eel4 ,9 addition to be+ a complete ma/] ( ! te*nical "p ( 8 bus9ess1 x is also desirable t ! up-to-date workman %\ld be famili> ) ! subject f a hi/orical po9t ( view4 ,to aid 9 su* an und]/&+ ( ! matt] we h translat$ f ,l',almana* de l',horolog]ie et de la ,bij\t]ie ! matt] conta9$ 9 ! foll[+ *apt]4 ,,*apt] ,,iv4 ,,hi/ory ,,( ,,escapem5ts4 ,x c\ld n h be5 long aft] man fir/ became cognizant ( 8 reason+ faculties t he began to take m or less notice ( ! flight ( "t4 ,! motion ( ! sun by day & ( ! moon & />s by night s]v$ to w>n him ( ! recurr+ p]iods ( light & d>kness4 ,by not+ ! position ( ^! /ell> bodies dur+ 8 lonely vigils1 he soon became pr(ici5t 9 r\ghly divid+ up ! cycle into sections1 :i* he d5om9at$ ! h\rs ( ! day & ( ! night4 ,primitive at fir/1 8 me?ods 7 simple1 8 ne$s few & 8 "t abundant4 ,increase 9 numb]s1 multiplicity ( duties1 & division ( occupation began to make x imp]ative t a m sy/ematic foll[+ ( ^! occupations %\ld be in/itut$1 & ) ?is end 9 view he contriv$1 by means ( burn+ lights or by re/rict+ ! fl[+ ( wat] or ! fall+ ( weights1 to subdivide into conv5i5t int]vals & 9 a tol]ably satisfactory mann] ! p]iods ( light4 ,^! mode/ means !n 7 ! fir/ /eps t[>d ! exact subdivisions ( "t :i* we n[ enjoy4 ,unre/1 progress1 discont5t ) ?+s t be1 we mu/ ackn[l$ge1 h1 f ! appe>ance ( ! fir/ clock to ! pres5t h\r1 be5 ! p[]s :i* h driv5 on ! inv5tive g5ius ( wat* & clockmak]s to designate "s new & m acceptable sy/em = regulat+ ! c\rse ( ! movem5t4 ,9 consequ5ce ( ?is re/less se>* aft] ! be/1 a v consid]able numb] ( escapem5ts h be5 inv5t$ & made up1 bo? = clocks & wat*es2 only a few1 h[ev]1 ( ! almo/ numb]less sy/ems h surviv$ ! te/ ( "t & be5 adopt$ 9 ! manufacture ( ! timepiece z we "k x n[4 ,inde$1 _m su* inv5tions nev] pass$ ! exp]im5tal /age1 & yet x w\ld be v int]e/+ to ! pr(essional horologi/1 ! appr5tice & ev5 ! layman to become m intimately acqua9t$ ) ! va/ v>iety ( inv5tions made ^u ?is doma9 s9ce ! inception ( horological sci5ce4 ,und\bt$ly1 a complete collection ( all ! escapem5ts inv5t$ w\ld con/itute a mo/ in/ructive "w = ! progressive wat*mak]1 & :ile we are wait+ = a compet5t au?or to take su* an exhau/ive "w ^u 8 h&s1 we %all endeavor to op5 ! way & tru/ t a numb] ( volunt>y collaborators w come =w>d & assi/ u to ! ext5t ( _! ability 9 fill+ up ! *9ks4 ,,problems ,,to ,,be ,,solv$4 ,! problem to be solv$ by means ( ! escapem5t has always be5 to gov]n1 )9 limits precise & p]fectly regul>1 if x be possible1 ! fl[ ( ! motive =ce2 t means ! procession ( ! :eel-"w &1 z a consequ5ce1 ( ! h&s !reto atta*$4 ,at fir/ blu% x seems z if a cont9ually-mov+ gov]nor1 su* z is 9 use on /eam eng9es1 = example1 ought to fulfil ! conditions1 & attempts h accord+ly be5 made ^u ?is l9e ) results :i* h prov5 entirely unsatisfactory4 ,hav+ ?or\ghly sift$ ! _m v>ieties at h&1 x has be5 f9ally det]m9$ t ! only means kn[n to provide ! mo/ regul> fl[ ( p[] consi/s 9 int]mitt5tly int]rupt+ ! procession ( ! :eel-"w1 & !reby ga9+ a p]iodically uni=m movem5t4 ,:atev] may be ! sy/em or k9d ( escapem5t employ$1 ! function+ ( ! me*anism is *>act]iz$ by ! susp5sion1 at regul> int]vals1 ( ! rotation ( ! la/ :eel ( ! tra9 & 9 transmitt+ to a regulator1 be x a balance or a p5dulum1 ! p[] s5t into t :eel4 ,,escapem5t ,,! ,,mo/ ,,ess5tial ,,"p4 ,( all ! p>ts ( ! timepiece ! escapem5t is !n ! mo/ ess5tial2 x is ! "p :i* assures regul>ity 9 ! runn+ ( ! wat* or clock1 & t "p ( p>ts t end[s ! piece ) real value4 ,! mo/ p]fect escapem5t w\ld be t "o :i* %\ld p]=m its duty ) ! lea/ influ5ce ^u ! "t ( oscillation or vibration ( ! regulat+ organ4 ,! /oppage ( ! tra9 by ! escapem5t is br\ght ab\t 9 diff]5t ways1 :i* may be ga!r$ "u ?ree heads or categories4 ,9 ! two :i* we %all m5tion fir/1 ! /op is effect$ directly ^u ! axis ( ! regulator1 or aga9/ a piece :i* =ms a "p ( t axis2 ! too? ( ! escape :eel at ! mom5t ( its dis5gagem5t rema9s support$ ^u or aga9/ t /op4 ,9 ! fir/ escapem5t inv5t$ &1 inde$1 9 "s actually employ$ to-day = c]ta9 k9ds ( timekeep]s1 we notice dur+ ! lock+ a retrograde movem5t ( ! escape :eel2 to ?is k9d ( movem5t has be5 giv5 ! "n ( recoil escapem5t4 ,x 0 recogniz$ by ! frat]nity t ?is recoil 0 prejudicial to ! regul>ity ( ! runn+ ( ! me*anism &1 aft] ! inv5tion ( ! p5dulum & ! spiral1 inv5tive mak]s succe$$ 9 replac+ ?is sort ( escapem5t ) "o :i* we n[ call ! dead-beat escapem5t4 ,9 ?is latt] ! :eel1 /opp$ by ! axis ( ! regulator1 rema9s immovable up to ! in/ant ( its dis5gagem5t or unlock+4 ,9 ! ?ird category h be5 collect$ all ^? =ms ( escapem5t :]e9 ! escape :eel is lock$ by an int]m$iate piece1 indep5d5t ( ! regulat+ organ4 ,?is latt] p]=ms its vibrations ( oscillation q )\t int]f]5ce1 & x is only 9 contact ) ! tra9 dur+ ! v brief mom5t ( impulse :i* is ne$ful to keep ! regulat+ organ 9 motion4 ,?is category con/itutes :at is kn[n z ! deta*$ escapem5t class4 ,( ! recoil escapem5t ! pr9cipal types are3 ! v]ge escapem5t or cr[n-:eel escapem5t = bo? wat*es & clocks1 & ! recoil an*or escapem5t = clocks4 ,! cyl9d] & duplex escapem5ts = wat*es & ! ,graham an*or escapem5t = clocks are /yles ( ! dead-beat escapem5t mo/ (t5 employ$4 ,among ! deta*$ escapem5ts we h ! lev] & det5t or *ronomet] escapem5ts = wat*es2 = clocks !re is no fix$ type ( deta*$ lev] & x f9ds no application to-day4 ,,! ,,v]ge ,,escapem5t4 ,! v]ge escapem5t1 call$ also ! cr[n-:eel escapem5t1 is by f> ! simple/ & pres5ts ! lea/ difficulty 9 con/ruction4 ,we regret t ! _w does n "k ei!r ! "n ( its orig9ator nor ! date at :i* ! inv5tion made its fir/ appe>ance1 b x seems to h foll[$ v closely ^u ! bir? ( me*anical horology4 ,up to #agej x 0 employ$ to ! exclusion ( almo/ all ! o!rs4 ,9 #ahej a v l>ge "p ( ! ord9>y comm]cial wat*es 7 /ill fitt$ ) ! v]ge escapem5t1 & x is /ill us$ "u ! =m ( recoil an*or 9 clocks1 eighty ye>s aft] ! inv5tion ( ! cyl9d] escapem5t1 or 9 #ahjb4 ,f]d9& ,b]?\d1 9 8 ,hi/ory ( ! ,measurem5t ( ,"t1 says ( ! balance-:eel escapem5t3 ,s9ce ! epo* ( its inv5tion an inf9ite v>iety ( escapem5ts h be5 con/ruct$1 b ! "o :i* is employ$ 9 ord9>y wat*es = e-day use is /ill ! be/4 ,9 ref]r+ to our illu/rations1 we beg fir/ to call att5tion to ! plates m>k$ ,figs4 #ade & #adf4 ,?is plate gives u two views ( a v]ge escapem5t2 t is1 a balance :eel & a v]ge =m$ by its two opposite pallets4 ,! views are int5tionally pres5t$ 9 ?is mann] to %[ t ! v]ge ,v may be dispos$ ei!r horizontally1 z 9 ,fig4 #adf1 or v]tically1 z 9 ,fig4 #ade4 ,illu/ration3 ,figs4 #ade & #adf ,illu/ration3 ,fig4 #adg ,let u imag9e t our draw+ is 9 motion1 !n w ! too? d1 ( ! cr[n :eel ,r1 be pu%+ aga9/ ! pallet ,p1 & j ^u ! po9t ( slipp+ by or escap+1 :ile ! opposite too? e is j ab\t to imp+e ^u ! advanc+ pallet ,p'4 ,?is x does1 & w at fir/1 ?r\gh ! impulse receiv$ f ! too? d be =c$ back by ! mom5tum ( ! pallet1 t is1 suff] a recoil2 b on ! return j\rney ( ! pallet ,p'1 ! too? e w !n add its impulse to ! rec$+ pallet4 ,! too? e hav+ ?us accompli%$ its mission1 w n[ slip by & ! too? c w come 9 lock ) ! pallet ,p &1 aft] ! mann] j describ$ = e1 cont9ue ! escapem5t4 ,usually ^! escape :eels are provid$ ) tee? to ! numb] ( #aa1 #ac or #ae1 & always unev54 ,a great advantage possess$ by ?is =m ( escapem5t is t x does n require any oil1 & x may be made to "w ev5 "u v inf]ior con/ruction4 ,,olde/ ,,arrangem5t ,,( ,a ,,cr[n-,,:eel ,,escapem5t4 ,illu/ration3 ,fig4 #adh ,plate #adg %[s u ! olde/ kn[n arrangem5t ( a cr[n-:eel escapem5t 9 a clock4 ,r is ! cr[n :eel or balance :eel act+ ^u ! pallets ,p & ,p'1 :i* =m "p ( ! v]ge ,v4 ,?is v]ge is susp5d$ z lightly z possible ^u a pliable cord ,c & c>ries at its upp] end two arms1 ,b & ,b1 call$ adju/]s1 =m+ ! balance4 ,two small weights ,d ,d1 adapt$ to movem5t along ! rules or adju/]s s]ve to regulate ! duration ( a vibration4 ,9 ,fig4 #adh we h ! arrangem5t adopt$ 9 small timepieces & wat*es3 ,b repres5ts ! regulator 9 ! =m ( a circul> balance1 b n yet furni%$ ) a spiral regulat+ spr+2 c is ! la/ :eel ( ! tra9 & call$ ! f\r? :eel1 x be+ t numb] di/ant f ! great :eel4 ,z w be se51 ! v]ge provid$ ) its pallets is v]tically plac$1 z 9 ! prec$+ plate4 ,illu/ration3 ,fig4 #adi ,"h x w quickly be se5 t reg>d$ f ! /&po9t ( regul>ity ( motion1 ?is arrangem5t c be productive ( b meag] results4 ,subject$ z x is to ! influ5ce ( ! slighte/ v>iation 9 ! motive p[] & ( ! lea/ j> or %ak+1 a balance :eel escapem5t improvid$ ) a regulator conta9+ )9 itself a regulat+ =ce1 c\ld n possibly give =? any?+ else ?an an un/eady movem5t4 ,h[ev]1 me*anical clocks fitt$ ) ?is escapem5t (f] indisputable advantages ov] ! anci5t clepsydra2 9 spite ( _! imp]fections !y r5d]$ important s]vices1 especially aft] ! /rik+ movem5t _h be5 add$4 ,= m ?an ?ree c5turies bo? ?is crude escapem5t & ! crud] regulator 7 suff]$ to cont9ue 9 ?is /ate )\t a ?\ght ( improvem5t2 ev5 9 #afjj1 :5 ,galileo discov]$ ! law gov]n+ ! oscillation ( ! p5dulum1 !y did n suspect h[ important ?is discov]y 0 = ! sci5ce ( "t measurem5t4 ,,galileo',s ,,exp]im5ts4 ,illu/ration3 ,fig4 #aej ,galileo1 himself1 9 spite ( 8 g5ius = inve/igation1 0 s engross$ 9 8 rese>*es t he c\ld n seem to dis5gage ! simple p5dulum f ! comp\nd p5dulums to :i* he devot$ 8 att5tion2 besides1 he attribut$ to ! oscillation an absolute g5]ality ( iso*ronism1 :i* !y did n possess2 nor did he "k h[ to apply 8 fam\s discov]y to ! measurem5t ( "t4 ,9 fact1 x 0 n till aft] m ?an half a c5tury _h elaps$1 9 #afeg1 to be exact1 t ! celebrat$ ,dut* ma!matician & a/ronom]1 ,huyg5s1 publi%$ 8 memoirs 9 :i* he made kn[n to ! _w ! degree ( p]fection :i* w\ld accrue to clocks if ! p5dulum 7 adopt$ to regulate _! movem5t4 ,illu/ration3 ,fig4 #aea ,an attempt 0 inde$ made to snat* f ,huyg5s & conf] ^u ,galileo ! glory ( hav+ fir/ appli$ ! p5dulum to a clock1 b ?is attempt n hav+ be5 made until "s "t aft] ! publication ( ,huyg5s' ,memoirs1 x 0 impossible to place any fai? 9 ! cont5tion4 ,if ,galileo _h inde$ solv$ ! beautiful problem1 bo? 9 ! conception & ! fact1 ! honor ( ! discov]y 0 lo/ to him by ! laz9ess & neglig5ce ( 8 pupil1 ,viviani1 ^u :om he _h plac$ su* high hopes4 ,"o ?+ is c]ta91 t ! "r ( priority ( ! discov]y & ! recognition ( ! entire _w has be5 inconte/ably be/[$ ^u ,huyg5s4 ,! escapem5t :i* ,galileo is suppos$ to h conceiv$ & to :i* he appli$ ! p5dulum1 is %[n 9 ,fig4 #adi4 ,! :eel ,r is suppli$ ) tee?1 :i* lock aga9/ ! piece ,d atta*$ to a lev] pivot$ at a1 & also ) p9s calculat$ to imp>t impulses to ! p5dulum ?r\gh ! pallet ,p4 ,! arm ,l s]ves to dis5gage or unlock ! :eel by lift+ ! lev] ,d ^u ! return oscillation ( ! p5dulum4 ,illu/ration3 ,fig4 #aeb ,illu/ration3 ,fig4 #aec ,a c>eful /udy ( ,fig4 #aej w discov] a simple transposition :i* x became necess>y to make 9 ! clocks1 = ! effectual adaptation ( ! p5dulum to _! regulation4 ,! v]ge ,v 0 set up horizontally & ! p5dulum ,b1 susp5d$ freely f a flexible cord1 receiv$ ! impulses ?r\gh ! int]m$iation ( ! =k$ arm ,f1 :i* =m$ a "p ( ! v]ge4 ,at fir/ ?is =k$ arm 0 n ?\ght (1 = ! p5dulum itself =m$ a "p ( ! v]ge4 ,a f>-rea*+ /ep _h be5 tak51 b x soon became app>5t t p]fection 0 /ill a long way (f4 ,! cr[n-:eel escapem5t =cibly incit$ ! p5dulum to wid] oscillations2 ^! oscillations n be+ z ,galileo _h believ$1 ( unv>i$ durations1 b !y v>i$ s5sibly ) ! int5sity ( ! motive p[]4 ,,! ,,atta9m5t ,,( ,,iso*ronism ,,by ,,huyg5s4 ,huyg5s r5d]$ 8 p5dulum iso*ron\s2 t is1 compell$ x to make its oscillations ( equal duration1 :atev] might be ! arc describ$1 by susp5d+ ! p5dulum betwe5 two metallic curves c c'1 ea* "o =m$ by an arc ( a cycloid & aga9/ :i* ! susp5d+ cord mu/ lie ^u ea* =w>d or backw>d oscillation4 ,we %[ ?is device 9 ,fig4 #aea4 ,9 great oscillations1 & by t we mean oscillations "u a great] impulse1 ! p5dulum w\ld ?us be %ort5$ & ! %ort5+ w\ld correct ! "t ( ! oscillation4 ,h[ev]1 ! application ( an exact cycloidal arc 0 a matt] ( no little difficulty1 if n an impossibility 9 practice1 & practical m5 began to grope ab\t 9 se>* ( an escapem5t :i* w\ld p]mit ! use ( %ort] arcs ( oscillation4 ,at ,london ! horologi/1 ,g4 ,clem5t1 solv$ ! problem 9 #afge ) 8 rack escapem5t & recoil an*or4 ,9 ! int]val o!r means 7 inv5t$1 especially ! addition ( a second p5dulum to correct ! irregul>ities ( ! fir/4 ,su* an escapem5t is pictur$ 9 ,fig4 #aeb4 ,! v]ge is aga9 v]tical & c>ries ne> its upp] end two arms ,d ,d1 :i* are ea* connect$ by a cord ) a p5dulum4 ,! two p5dulums oscillate con/antly 9 ! inv]se s5se ! "o to ! o!r4 ,illu/ration3 ,fig4 #aed ,illu/ration3 ,fig4 #aee ,,ano!r ,,two-,,p5dulum ,,escapem5t4 ,we %[ ano!r escapem5t ) two p5dulums 9 ,fig4 #aec4 ,^! are fix$ directly ^u two axes1 ea* "o c>ry+ a pallet ,p ,p' & a segm5t ( a too!d :eel ,d ,d1 :i* produces ! effect ( solid>ity betwe5 !m4 ,! two p5dulums oscillate inv]sely "o to ! o!r1 & "o aft] ! o!r receives an impulse4 ,?is escapem5t 0 con/ruct$ by ,jean ,bapti/e ,dut]tre1 ( ,p>is4 ,fig4 #aed %[s ano!r disposition ( a d\ble p5dulum4 ,:ile ! p5dulum "h is d\ble1 x has b "o bob2 x receives ! impulse by means ( a d\ble =k ,f4 ,c ,c repres5ts ! cycloidal curves & are plac$ ) a view ( correct+ ! inequality 9 ! duration ( ! oscillations4 ,9 wat*es ! circul> balances did n af=d any bett] results ?an ! regulat+ rods or rules ( ! clocks1 & ! p5dulum1 ( c\rse1 0 out ( ! "q altoge!r2 x !re=e became imp]ative to inv5t "s o!r regulat+ sy/em4 ,illu/ration3 ,fig4 #aef ,illu/ration3 ,fig4 #aeg ,x occur$ to ! ,abb d',hautefeuille to =m a sort ( resili5t me*anism by atta*+ "o end ( a hog's bri/le to ! plate & ! o!r to ! balance ne> ! axis4 ,?\gh imp]fect 9 results1 ?is 0 nev]!less a brilliant idea1 & x 0 b a %ort /ep to replace ! bri/le ) a /raight & v flexible spr+1 :i* lat] 0 supplant$ by "o coil$ up l a s]p5t2 b 9 spite ( ?is advancem5t1 ! wat*es did n keep mu* bett] "t4 ,h>rison1 ! celebrat$ ,engli% horologi/1 _h rec\rse to two artifices1 ( :i* ! "o consi/$ 9 giv+ to ! pallets ( ! escapem5t su* a curvature t ! balance c\ld be l$ back ) a velocity correspond+ to ! ext5sion ( ! oscillation2 ! second consi/$ ( an accessory piece1 ! resultant action ( :i* 0 analog\s to t ( ! cycloidal curves 9 connection ) ! p5dulum4 ,,correct+ ,,irregul>ities ,,9 ,,! ,,v]ge ,,escapem5t4 ,huyg5s attempt$ to correct ^! irregul>ities 9 ! v]ge escapem5t 9 wat*es by amplify+ ! arc ( oscillation ( ! balance itself4 ,he con/ruct$ = t purpose a pir\ette escapem5t %[n 9 ,fig4 #aee1 9 :i* a too!d :eel ,a adju/$ ^u ! v]ge ,v s]ves z an int]m$i>y betwe5 t & ! balance ,b1 ^u ! axis ( :i* 0 fix$ a p9ion ,d4 ,by ?is me?od he obta9$ ext5d$ arcs ( vibration1 b ! vibrations 71 z a consequ5ce1 v sl[1 & !y /ill rema9$ subject to all ! irregul>ities aris+ f ! v>iation 9 ! motive p[] z well z f %ocks4 ,a little lat]1 b ab\t ! same epo*1 a c]ta9 ,dr4 ,hook1 ( ! ,royal ,society ( ,london1 contriv$ ano!r arrangem5t by means ( :i* he succe$$1 s x appe>$ to him at lea/1 9 greatly dim9i%+ ! influ5ce ( %ock ^u ! escapem5t2 b _m o!r1 p]haps great]1 inconv5i5ces caus$ 8 inv5tion to be spe$ily reject$4 ,we %all give our read]s an idea ( :at ,dr4 ,hook's escapem5t 0 l4 ,illu/ration3 ,fig4 #aeh ,illu/ration3 ,fig4 #aei ,on look+ at ,fig4 #aef we see ! escape :eel ,r1 :i* 0 flat & 9 ! =m ( a rat*et2 x 0 provid$ ) two balances4 ,b ,b engag+ ea* o!r 9 tee?1 ea* "o c>ry+ a pallet ,p ,p' ^u its axis2 ! axes ( ! ?ree :eels be+ p>allel4 ,n[1 9 our draw+1 ! too? a ( ! escape :eel ex]ts its lift ^u ! pallet ,p'2 :5 ?is too? escapes ! too? b w fall ^u ! pallet ,p' on ! opposite side1 a recoil w be produc$ ^u ! action ( ! two unit$ balances1 !n ! too? b w give its impulse 9 ! contr>y direction4 ,consid]able analogy exi/s betwe5 ?is =m ( escapem5t & t %[n 9 ,fig4 #aec & int5d$ = clocks4 ,?is 0 ! busy era 9 ! wat*mak]'s l9e4 ,all ! great heads 7 pond]+ ^u ! subject & ev]yone 0 on ! qui vive = ! newe/ ?+ 9 ! art4 ,9 #afgd ,huyg5s br\ght out ! fir/ wat* hav+ a regulat+ spr+ 9 ! =m ( a spiral2 ! m]it ( ?is inv5tion 0 disput$ by ! ,engli% savant1 ,dr4 ,hook1 :o pret5d$1 z did ,galileo1 9 ! application ( ! p5dulum1 to h priority 9 ! idea4 ,huyg5s1 :o _h discov]$ & correct$ ! irregul>ities 9 ! oscillations ( ! p5dulum1 did n ?9k ( ^? ( ! balance ) ! spiral spr+4 ,& x 0 n until ! close ( ! ye> #agej t ,pi]re ,le ,roy & ,f]d9& ,b]?\d /udi$ ! conditions ( iso*ronism p]ta9+ to ! spiral4 ,,an ,,inv5tion ,,t ,,creat$ ,,mu* ,,en?usiasm4 ,h[ev] t may be1 ?is magnific5t inv5tion1 l ! adaptation ( ! p5dulum1 0 welcom$ ) g5]al en?usiasm ?r\gh\t ! sci5tific _w3 )\t spiral & )\t p5dulum1 no o!r escapem5t b ! recoil escapem5t 0 possible2 a new highway 0 ?us op5$ to ! se>*]s4 ,! wat] clocks 7clepsydr7 & ! h\r glasses disappe>$ completely1 & ! timepieces :i* _h till !n only m>k$ ! h\rs1 hav+ be5 p]fect$ up to ! po9t ( keep+ m exact "t1 7 grac$ ) ! addition ( ano!r h& to tell (f ! m9utes4 ,illu/ration3 ,fig4 #afj ,illu/ration3 ,fig4 #afa ,x 0 n until #afie t ! fir/ dead-beat escapem5t appe>$ ^u ! sc5e2 dur+ ! int]val ( ov] tw5ty ye>s all ?\ght _h be5 direct$ t[>d ! "o goal1 viz43 ! p]fect+ ( ! v]ge escapem5t2 b practice demon/rat$ t no o!r arrangem5t ( ! p>ts 0 sup]ior to ! orig9al idea4 ,= ! b5efit ( our read]s we %all give a few ( ^! attempts at bett]m5t1 & y may see = y\rselves :]e9 ! trials fail$4 ,fig4 #aeg repres5ts a v]ge escapem5t ) a rat*et :eel1 ! pallets ,p ,p' be+ c>ri$ ^u sep>ate axes4 ,! two axes are rigidly connect$1 ! "o to ! o!r1 by means ( ! arms o o'4 ,"o ( ! axes c>ries besides ! =k ,f1 :i* transmits ! impulse to ! p5dulum ,b4 ,9 ! front view1 at ! "r ( ! plate1 = ! sake ( cle>ness ! =k & ! p5dulum are n %[n1 b "o may easily see ! jo9ture ( ! arms o o' & _! mode ( op]ation4 ,ano!r v peculi> arrangem5t ( ! v]ge escapem5t we %[ at ,fig4 #aeh4 ,9 ?is !re are two :eels1 "o1 ,r'1 a small "o 9 ! =m ( a rat*et2 ! o!r1 ,r1 some:at l>g]1 call$ ! balance :eel1 b be+ suppli$ ) /raight & sl5d] tee?4 ,! v]ge ,v c>ry+ ! two pallets is pivot$ 9 ! v]tical diamet] ( ! l>g] :eel4 ,! front view %[s ! modus op]&i ( ?is comb9ation1 :i* is practically ! same z ! o!rs4 ,! too? a ( ! l>ge :eel ex]ts its =ce ^u ! pallet ,p1 & ! too? b ( ! rat*et w enc\nt] ! pallet ,p'4 ,?is pallet1 aft] suff]+ its recoil1 w receive ! impulse communicat$ by ! too? b4 ,?is escapem5t surely c\ld n h giv5 mu* satisfaction1 = x (f]s no advantage ov] ! o!rs1 besides x is ( v difficult con/ruction4 ,illu/ration3 ,fig4 #afb ,illu/ration3 ,fig4 #afc ,,+5i\s ,,attempts ,,at ,,solution ,,( ,a ,,difficult ,,problem4 ,mu* +5uity to a wor?y end1 b ( little practical value1 is display$ 9 ^! v>i\s attempts at ! solution ( a v difficult problem4 ,9 ,fig4 #aei we h a me*anism comb9+ two escape :eels engag+ ea* o!r 9 ge>2 ( ! two :eels1 ,r ,r'1 "o alone is driv5 directly by ! tra91 ! o!r be+ turn$ 9 ! opposite direction by its comrade4 ,bo? are furni%$ ) p9s c c'1 :i* act alt]nately ^u ! pallets ,p ,p' dispos$ 9 ! same plane ^u ! v]ge ,v & pivot$ betwe5 ! :eels4 ,our draw+ repres5ts ! escapem5t at ! mom5t :5 ! p9 ,c' deliv]s its impulse1 & ?is hav+ be5 accompli%$1 ! lock+ takes place ^u ! p9 ,c ( ! o!r :eel ^u ! pallet ,p'4 ,ano!r sy/em ( two escape :eels is %[n 9 ,fig4 #afj1 b 9 ?is case ! two :eels ,r ,r are driv5 9 a l direction by ! la/ :eel ,a ( ! tra94 ,! op]ation ( ! escapem5t is ! same z 9 ,fig4 #aei4 ,illu/ration3 ,fig4 #afd ,illu/ration3 ,fig4 #afe ,9 ,fig4 #afa we h a dep>ture f ! road ord9>ily pursu$4 ,"h we see an escapem5t comb9+ two lev]s1 inv5t$ by ! ,*evali] de ,b?une & appli$ by ,m4 ,?i\t1 ma/]-horologi/1 at ,p>is 9 #agbg4 ,p ,p' are ! two lev]s or pallets sep>ately pivot$4 ,^u ! axis ,v1 ( ! lev] ,p1 is fix$ a =k :i* communicates ! motion to ! p5dulum4 ,! two lev]s are intimately connect$ by ! two arms ,b ,b'1 ( :i* ! =m] c>ries an adju/+ screw1 a well-conceiv$ addition = regulat+ ! op5+ betwe5 ! pallets4 ,! c\nt]-weight ,c compels con/ant contact betwe5 ! arms ,b ,b'4 ,! function is always ! same1 ! recoil & ! impulsion op]ate ^u ! two pallets simultane\sly4 ,?is escapem5t enjoy$ a c]ta9 degree ( success1 hav+ be5 employ$ by a numb] ( horologi/s :o modifi$ x 9 v>i\s ways4 ,,v>i\s ,,modifications ,"s ( ^! modifications we %all %[4 ,= ! fir/ example1 !n1 let ,fig4 #afb illu/rate4 ,9 ?is arrangem5t ! =k is c>ri$ ^u ! axis ( ! pallet ,p'1 :i* effectually does away ) ! c\nt]-weight ,c1 z %[n4 ,some:at m complicat$1 b ( ! same intr9sic nature1 is ! arrangem5t display$ 9 ,fig4 #afc4 ,we %\ld n imag9e t x enjoy$ a v ext5sive application4 ,"h ! two lev]s are completely indep5d5t ( ea* o!r2 !y act ^u ! piece ,b ,b ^u ! axis ,v ( ! =k4 ,! c\nt]-weights ,c ,c' ma9ta9 ! arms c>ry+ ! roll]s ,d ,d' 9 contact ) ! piece ,b ,b' :i* ?us receives ! impulse f ! :eel ,r4 ,two adju/+ screws s]ve to place ! escapem5t ^u ! c5t]4 ,by degrees ^! fanta/ic con/ructions 7 ab&on$ to make way = ! an*or recoil escapem5t1 :i* 0 inv5t$1 z we h said1 9 #afge1 by ,g4 ,clem5t1 a horologi/1 ( ,london4 ,9 ,fig4 #afd we h ! disposition ( ! p>ts z fir/ arrang$ by ?is arti/4 ,"h ! pallets are replac$ by ! incl9es ,a & ,b ( ! an*or1 :i* is pivot$ at ,v ^u an axis to :i* is fix$ also ! =k4 ,! too? a escapes f ! incl9e or lev] ,a1 & ! too? b imm$iately re/s ^u ! lev] ,b2 by ! action ( ! p5dulum ! escape :eel suff]s a recoil z 9 ! pallet escapem5t1 & on ! return ( ! p5dulum ! too? c gives out its impulse 9 ! contr>y direction4 ,) ?is new sy/em x became possible to increase ! weight ( ! bob & at ! same "t less5 ! effective motor p[]4 ,! travel ( ! p5dulum1 or arc ( oscillation1 be+ r$uc$ 9 a m>k$ degree1 an accuracy ( rate 0 obta9$ f> sup]ior to t ( ! cr[n-:eel escapem5t4 ,h[ev]1 ?is new application ( ! recoil escapem5t 0 n adopt$ 9 ,france until #afie4 ,illu/ration3 ,fig4 #aff ,illu/ration3 ,fig4 #afg ,! travel ( ! p5dulum1 ?\gh greatly r$uc$1 /ill surpass$ 9 bread? ! arc 9 :i* x is iso*ron\s1 & repeat$ ef=ts 7 made to give su* %ape to ! lev]s z w\ld compel its oscillation )9 ! arc ( equal "t2 a motion :i* is1 z 0 recogniz$ ev5 at t epo*1 ! prime requisite to a precise rat+4 ,?us1 9 #agbj1 ,juli5 ,l]oy occupi$ himself work+ out ! prop] %apes = ! incl9es to produce ?is desir$ iso*ronism4 ,se>*+ along ! same pa?1 ,f]d4 ,b]?\d con/ruct$ an escapem5t repres5t$ by ! ,fig4 #afe4 ,9 x we see ! same incl9es ,a ,b ( ! =m] con/ruction1 b ! lock+ is effect$ aga9/ ! slides ,c & ,d1 ! curv$ faces ( :i* produce iso*ron\s oscillations ( ! p5dulum4 ,! too? b imp>ts its lift & ! too? c w lock aga9/ ! face ,c2 aft] hav+ pass$ ?r\gh its recoil motion ?is too? c w butt aga9/ ! incl9e ,a & "w out its lift or impulse ^u x4 ,,! ,,gable ,,escapem5t4 ,illu/ration3 ,fig4 #afh ,illu/ration3 ,fig4 #afi ,! gable escapem5t1 %[n 9 ,fig4 #aff1 all[s ! use ( a heavi] p5dulum1 at ! same "t ! an*or embraces )9 its jaws a great] numb] ( ! escape-:eel tee?2 an arrangem5t aft] ?is mann] leads to ! conclusion t ) ^! long lev]s ( ! an*or ! friction w be consid]ably increas$ & ! recoil faces w1 z a consequ5ce1 be quickly worn away4 ,)\t d\bt1 ?is 0 inv5t$ to p]mit ( op5+ & clos+ ! contact po9ts ( ! an*or m easily4 ,"u ! "n ( ! ,engli% recoil an*or !re came into use an escapem5t ) a r$uc$ gable1 :i* embrac$ few] tee? betwe5 ! pallets or incl9es2 we give a repres5tation ( ?is 9 ,fig4 #afg4 ,?is sy/em seems to h be5 mod]ately successful4 ,! an*or recoil escapem5t 9 use 9 ,g]many to-day is demon/rat$ 9 ,fig4 #afh2 ?is arrangem5t is also f\nd 9 ! ,am]ican clocks4 ,z we see1 ! an*or is compos$ ( a s+le piece ( curv$ /eel b5t to ! desir$ curves4 ,clocks provid$ ) ?is escapem5t keep reasonably good "t2 ! resi/ance ( ! recoils comp5sate 9 a measure = ! want ( iso*ronism 9 ! oscillations ( ! p5dulum4 ,ord9>y clocks require consid]ably m p[] to drive !m ?an f9] clocks &1 z a consequ5ce1 _! tick+ is v noisy4 ,sev]al means h be5 employ$ to damp5 ?is noise1 "o ( :i* we %[ 9 ,fig4 #afi4 ,illu/ration3 ,fig4 #agj ,"h ! an*or is compos$ ( two pieces1 ,a ,b1 screw$ ^u a plate ,h pivot+ at ,v4 ,9 _! arrangem5t ! two pieces repres5t1 z to di/ance & curvature1 ! c\nt]p>t ( ,fig4 #afh4 ,at ! mom5t ( impact _! extreme ends recoil or spr+ back f ! %ock ( ! escape tee?1 b ! resili5cy ( ! metal is calculat$ to be /rong en\gh to return !m imm$iately to ! contact /uds e e4 ,z a t]m9ation to ?is *apt]1 we %all m5tion ! use made at ! pres5t day ( ! recoil lev] escapem5t 9 repeat+ wat*es4 ,we give a diagram ( ?is con/ruction 9 ,fig4 #agj4 ,! lev] "h is int5d$ to re/ra9 & regulate ! motion ( ! small /rik+ "w4 ,x is pivot$ at ,v & is capable ( a v rapid oscillatory motion1 ! arc ( :i* may1 h[ev]1 be fix$ by ! /ud or /op ,d1 :i* limits ! sw+ ( ! fly ,c4 ,?is fly is ( "o piece ) ! lev] &1 toge!r ) ! /ud ,d1 det]m9es ! angul> motion ( ! lev]4 ,if ! angle be l>ge t means ! pa? ( ! fly be long1 !n ! /rik+ tra9 w move sl[ly2 b if ! tee? ( ! escape :eel ,r c j pass by )\t caus+ ! lev] to describe a supplem5t>y or ext5d$ arc1 ! /rik+ "w w run (f rapidly4 ,,*apt] ,v4 ,,putt+ ,,9 ,a ,,new ,,cyl9d]4 ,putt+ 9 a new cyl9d] is some?+ mo/ wat*mak]s fancy !y c d1 & d well2 b /ill x is a job v few workm5 c d & fulfill all ! requirem5ts a job ( ?is k9d dem&s "u ! ev]-v>y+ conditions & circum/ances pres5t$ 9 repairs ( ?is k9d4 ,x is well to expla9 some:at at ?is po9t3 ,suppose we h five wat*es tak5 9 ) brok5 cyl9d]s4 ,out ( ?is numb] probably two c\ld be pivot$ to advantage & make ! wat*es z good z ev]4 ,z to ! pivot+ ( a cyl9d]1 we w deal ) ?is lat] on4 ,! fir/ ?+ to d is to make an exam9ation ( ! cyl9d]1 n only to see if x is brok51 b also to det]m9e if pivot+ is go+ to br+ x out all "r4 ,let u imag9e t "s workman has1 at "s previ\s "t1 put 9 a new cyl9d]1 & in/ead ( putt+ 9 "o ( ! prop] size he has put "o 9 too l>ge or too small4 ,n[1 9 ei!r case he w\ld h to remove a portion ( ! escape-:eel too?1 t is1 %ort5 ! too?3 because1 if ! cyl9d] 0 too l>ge x w\ld n g 9 betwe5 ! tee?1 & consequ5tly ! tee? w\ld h to be cut or /on$ away4 ,if ! cyl9d] 0 too small1 aga9 ! tee? w\ld h to be cut away to all[ !m to ent] ! cyl9d]4 ,all workm5 h traditions1 rules "s call !m1 t !y g by 9 relation to ! "r way to dress a cyl9d] too?2 "s insi/+ t ! toe or po9t ( ! too? is ! only place :i* %\ld be tamp]$ )4 ,o!r workm5 insi/ t ! heel ( ! too? is ! prop] place4 ,n[1 ) all due consid]ation1 we w\ld say t 9 n9ety-n9e cases out ( a hundr$ ! prop] ?+ to d is to let ! escape-:eel tee? entirely alone4 ,z we c und]/&1 aft] a mom5t's ?\ght1 t x is impossible to h ! tee? ( ! escape :eel too long & h ! wat* run at all2 h5ce1 ! idea ( /on+ a cyl9d] escape-:eel too? %\ld n be tol]at$4 ,,escape-,,:eel ,,tee? vs4 ,,cyl9d]4 ,x w n d1 h[ev]1 to accept1 & take x = grant$ t ! escape-:eel tee? are all "r1 because 9 _m in/ances !y h be5 /on$ away & made too %ort2 b if we accept ?is condition z be+ ! case1 t is1 t ! escape-:eel tee? are too %ort1 :at is ! workman go+ to d ab\t x8 ,! own] ( ! wat* w n pay = a new escape :eel z well z a new cyl9d]4 ,! situation c be summ$ up ab\t 9 ?is way1 t we w h to make ! be/ we c out ( a bad job1 & pick out & fit a cyl9d] on a compromise idea4 ,9 reg>d to pick+ out a new cyl9d]1 x may n d to select "o ( ! same size z ! old "o1 f ! fact t ! old "o may n h be5 ( ! prop] size = ! escape :eel1 because1 ev5 9 new1 *eap wat*es1 ! workm5 :o run 9 ! escapem5t knew v well ! cyl9d] & escape :eel 7 n adapt$ = ea* o!r1 b !y 7 ! be/ he _h4 ,*apt] ,,ii1 on ! cyl9d] escapem5t1 w enable our read]s to ma/] ! subject & h5ce be bett] able to judge ( all[ances to be made 9 ord] to p]mit imp]fect mat]ial to be us$4 ,9 illu/ration1 let u imag9e t we h to put 9 a new cyl9d]1 & we h none ( precisely ! prop] size1 b we h !m bo? a m]e trifle too l>ge & too small1 & ! "q is :i* to use4 ,our advice is to use ! small] "o if x does n require ! escape-:eel tee? to be dress$1 t is1 made small]4 ,:y we make ?is *oice is bas$ on ! fact t ! small] cyl9d] %ell gives less friction1 & ! loss f drop--t is1 side play betwe5 ! escape-:eel tee? & ! cyl9d]--w be ! same 9 bo? in/ances except to *ange ! lo/ motion f inside to outside drop4 ,9 devis+ a sy/em to be appli$ to select+ a new cyl9d]1 we meet ! same tr\bles enc\nt]$ ?r\gh\t all wat*mak]s' repair "w1 & *ief among ^! are good & conv5i5t measur+ tools4 ,b ev5 ) p]fect measur+ tools we w\ld h to ex]cise good judgm5t1 z j expla9$4 ,9 ,*apt] ,,ii we gave a rule = det]m9+ ! outside diamet] ( a cyl9d] f ! diamet] ( ! escape :eel2 b su* rules & tables w1 9 n9e in/ances out ( t51 h to be modifi$ by att5dant circum/ances--z1 = in/ance1 ! ?ickness ( ! %ell ( ! cyl9d]1 :i* %\ld be "o-t5? ( ! out] diamet] ( ! %ell1 b ! %ell is usually ?ick]4 ,a tol]ably safe practical rule & "o also dep5d+ v mu* on ! workman's good judgm5t is1 :5 ! escape-:eel tee? h be5 %ort5$1 to select a cyl9d] giv+ ample cle>ance inside ! %ell to ! too?1 b by no means l>ge en\gh to fill ! space betwe5 ! tee?4 ,aft] /udy+ c>efully ! in/ructions j giv5 we ?9k ! workman w h no difficulty 9 select+ a cyl9d] ( ! "r diamet]4 ,,measur+ ,,! ,,heights4 ,! next ?+ is to get ! prop] heights4 ,?is is mu* m easily arriv$ at3 ! ma9 measurem5t be+ to h ! tee? ( ! escape :eel cle> ! upp] face ( ! l[] plug4 ,9 ord] to talk intellig5tly we w make a draw+ ( a cyl9d] & agree on ! prop] names = ! sev]al p>ts to be us$ 9 ?is *apt]4 ,su* draw+ is %[n at ,fig4 #aga4 ,! names are3 ,! holl[ cyl9d]1 made up ( ! p>ts ,a ,a' ,a'' ,a'''1 call$ ! %ell--,a is ! great %ell1 ,a' ! half %ell1 ,a'' ! bank+ slot1 & ,a''' ! small %ell4 ,! brass "p ,d is call$ ! collet & consi/s ( ?ree p>ts--! hairspr+ seat ,d1 ! balance seat ,d' & ! %\ld] ,d''1 aga9/ :i* ! balance is rivet$4 ,illu/ration3 ,fig4 #aga ,! fir/ measurem5t = fitt+ a new cyl9d] is to det]m9e ! height ( ! l[] plug face1 :i* corresponds to ! l9e x x1 ,fig4 #aga4 ,! height ( ?is face is su* z to p]mit ! escape :eel to pass freely ov] x4 ,9 select+ a new cyl9d] x is well to *oose "o :i* is z wide at ! bank+ slot ,a'' z is consi/5t ) safety4 ,! wid? ( ! bank+ slot is repres5t$ by ! dott$ l9es x u4 ,! dott$ l9e v repres5ts ! l5g? to :i* ! l[] pivot y is to be cut4 ,illu/ration3 ,fig4 #agb ,illu/ration3 ,fig4 #agc ,!re are sev]al little tools on ! m>ket us$ = mak+ ! necess>y measurem5ts1 b we w describe a v simple "o :i* c readily be made4 ,to d s1 take ab\t a ,no4 #e sew+ ne$le &1 aft] anneal+1 cut a screw ?read on x1 z %[n at ,fig1 #agb1 :]e ,e repres5ts ! ne$le & t t ! screw cut ^u x4 ,aft] ! screw is cut1 ! ne$le is aga9 h>d5$ & temp]$ to a spr+ temp] & a long1 ?9 pivot turn$ ^u x4 ,! ne$le is n[ %ap$ z %[n at ,fig4 #agc4 ,! pivot at s %\ld be small en\gh to g easily ?r\gh ! smalle/ hole jewel to be f\nd 9 cyl9d] wat*es1 & %\ld be ab\t #a_/af long4 ,! "p at r %\ld be ab\t #c_/af long & only r$uc$ 9 size en\gh to fully remove ! screw ?reads %[n at t4 ,illu/ration3 ,fig4 #agd ,illu/ration3 ,fig4 #age ,illu/ration3 ,fig4 #agf ,illu/ration3 ,fig4 #agg ,we next provide a sleeve or gu>d = our gage4 ,to d ?is we take a piece ( h>d brass bu%+ wire ab\t long &1 plac+ x 9 a wire *uck1 c5t] & drill x ne>ly ! entire l5g?1 leav+1 say1 #a_/aj at "o end to be c>ri$ ?r\gh ) a small drill4 ,we %[ at ,f1 ,fig4 #agd1 a magnifi$ longitud9al section ( su* a sleeve4 ,! piece ,f is drill$ f ! end l up to ! l9e q ) a drill ( su* a size t a female screw c be cut 9 x to fit ! screw on ! ne$le1 & ,f is tapp$ out to fit su* a screw f l up to ! dott$ l9e p4 ,! sleeve ,f is run on ! screw t & n[ appe>s z %[n at ,fig4 #age1 ) ! addition ( a h&le %[n at ,g ,g'4 ,x is evid5t t we c all[ ! pivot s to protrude f ! sleeve ,f any portion ( its l5g?1 & regulate su* protrusion by ! screw t4 ,to employ ?is tool = gett+ ! prop] l5g? to :i* to cut ! pivot y1 ,fig4 #aga1 we remove ! l[] cap jewel to ! cyl9d] pivot &1 hold+1 ! movem5t 9 ! left h&1 pass ! pivot s1 ,fig4 #age1 up ?r\gh ! hole jewel1 regulate ! l5g? by turn+ ! sleeve ,f until ! arm ( ! escape :eel ,i1 ,fig4 #agf1 w j turn free ov] x4 ,n[ ! l5g? ( ! pivot s1 :i* protrudes beyond ! sleeve ,f1 co9cides ) ! l5g? to :i* we mu/ cut ! pivot y1 ,fig4 #aga4 ,to hold a cyl9d] = r$uc+ ! l5g? ( ! pivot y1 we hold said pivot 9 a pair ( ?9-edg$ cutt+ pli]s1 z %[n at ,fig4 #agg1 :]e ,n ,n' repres5t ! jaws ( a pair ( cutt+ pli]s & y ! pivot to be cut4 ,! measurem5t is made by putt+ ! pivot s betwe5 ! jaws ,n ,n' z !y hold ! pivot4 ,! cutt+ is done by simply fil+ back ! pivot until ( ! "r l5g?4 ,,turn+ ,,! ,,pivots4 ,we h n[ ! pivot y ( ! prop] l5g?1 & :at rema9s to be done is to turn x to ! "r size4 ,we d n ?9k x advisable to try to use a split *uck1 al?\gh we h se5 workm5 drive ! %ell ,a ,a''' out ( ! collet ,d & !n turn up ! pivots y z 9 said wire *uck4 ,to our judgm5t !re is b "o *uck = turn+ pivots1 & ?is is ! cem5t *uck provid$ ) all ,am]ican la!s4 ,_m workm5 object to a cem5t *uck1 b we ?9k no man %\ld lay claim to ! "n ( wat*mak] until he ma/]s ! my/]y ( ! cem5t *uck4 ,x is n su* a v difficult matt]1 & ! skill once acquir$ w\ld n be p>t$ ) *eaply4 ,"o ?+ has s]v$ to put ! wax or cem5t *uck into disfavor1 & t is ! abom9able /uff sold by "s mat]ial h\ses = la! cem5t4 ,! orig9al cem5t1 made & pat5t$ by ,james ,bottum = 8 cem5t *uck1 0 made up ( a r complicat$ mixture2 b all ! sub/ances really dem&$ 9 su* cem5t are ultram>9e blue & a good quality ( %ellac4 ,^! +r$i5ts are comp\nd$ 9 ! proportion ( #h p>ts ( %ellac & #a "p ( ultram>9e--all by weight4 ,,h[ ,,to ,,use ,a ,,cem5t ,,*uck4 ,! %ellac is melt$ 9 an iron vessel1 & ! ultram>9e add$ & /irr$ to incorporate ! p>ts4 ,c>e %\ld be obs]v$ n to burn ! %ellac4 ,:ile w>m1 ! melt$ mass is p\r$ on to a cold slab ( iron or /one1 & :ile pla/ic made into /icks ab\t 9 diamet]4 ,illu/ration3 ,fig4 #agh ,illu/ration3 ,fig4 #agi ,we %[ at ,fig4 #agh a side view ( ! out] end ( a cem5t *uck ) a cyl9d] 9 position4 ,we comm5ce to turn ! l[] pivot ( a cyl9d]1 all[+ ! pivot z to re/ at ! apex ( ! holl[ cone a1 z %[n4 ,!re is some?+ ( a trick 9 turn+ su* a holl[ cone & leav+ no tit or protub]ance 9 ! c5t]1 b x is important x %\ld be done4 ,a little practice w soon enable "o to ma/] ! job4 ,a grav] = ?is purpose %\ld be cut to r an oblique po9t1 z %[n at ,l1 ,fig4 #agi4 ,! slope ( ! sides to ! recess a1 ,fig4 #agh1 %\ld be to ab\t =ty-five degrees1 mak+ ! angle at a ab\t n9ety degrees4 ,! only way to insure p]fect accuracy ( c5t]+ ( a cyl9d] 9 a cem5t *uck is c5t] by ! %ell1 :i* is done by cutt+ a piece ( pegwood to a w$ge %ape & lett+ x re/ on ! ,t-re/2 !n hold ! edge ( ! pegwood to ! cyl9d] z ! la! revolves & ! cem5t s(t & pla/ic4 ,a cyl9d] s c5t]$ w be absolutely true4 ,! outl9e curve at c1 ,fig4 #agh1 repres5ts ! surface ( ! cem5t4 ,! next op]ation is turn+ ! pivot to ! prop] size to fit ! jewel4 ,?is is usually done by trial1 t is1 try+ ! pivot into ! hole 9 ! jewel4 ,a quick] way is to gage ! hole jewel & !n turn ! pivot to ! "r size1 z measur$ by micromet] calip]s4 ,9 "s cyl9d] wat*es ! end /one /&s at "s di/ance f ! out] surface ( ! hole jewel2 consequ5tly1 if ! measurem5t = ! l5g? ( ! pivot is tak5 by ! tool %[n at ,fig4 #age1 ! pivot w app>5tly be too %ort4 ,:5 ! l[] end /one is remov$ we %\ld take note if any all[ance is to be made = su* extra space4 ,! tr\ble :i* w\ld ensue f n provid+ = su* extra end %ake w\ld be t ! l[] edge ( ! half %ell1 %[n at e1 ,fig4 #aga1 w\ld /rike ! projection on :i* ! /alk ( ! too? is plant$4 ,aft] ! l[] pivot is turn$ to fit ! jewel ! cyl9d] is to be remov$ f ! cem5t *uck & ! upp] "p turn$4 ,! measurem5ts to be look$ to n[ are1 fir/1 ! entire l5g? ( ! cyl9d]1 :i* is und]/ood to be ! entire di/ance betwe5 ! inn] faces ( ! two end /ones1 & corresponds to ! di/ance betwe5 ! l9es v d1 ,fig4 #aga4 ,?is measurem5t c be got by remov+ bo? end /ones & tak+ ! di/ance ) a ,boley gage or a d\zieme calip]4 ,a ,,conv5i5t ,,tool ,,= ,,l5g? ,,measurem5t4 ,illu/ration3 ,fig4 #ahj ,a pair ( common p9ion calip]s slightly modifi$ makes z good a pair ( calip]s = l5g? measurem5t z "o c desire4 ,?is in/rum5t is made by ins]t+ a small screw 9 "o ( ! blades--! head on ! inn] side1 z %[n at f1 ,fig4 #ahj4 ,! idea ( ! tool is1 ! screw head f re/s 9 ! s9k ( ! cap jewel or end /one1 :ile ! o!r blade re/s on ! cock ov] ! balance4 ,aft] ! adju/+ screw to ! calip] is set1 ! spr+ ( ! blades all[s ( _! removal4 ,! top pivot z ( ! cyl9d] is next cut to ! prop] l5g?1 z indicat$ by ! space betwe5 ! scre:ead f & ! o!r blade ( ! p9ion calip]4 ,! upp] p9ion z is held 9 ! jaws ( ! cutt+ pli]s1 z %[n 9 ,fig4 #agg1 ! same z ! l[] "o 0 held1 until ! prop] l5g? betwe5 ! l9es d v1 ,fig4 #aga1 is secur$1 aft] :i* ! cyl9d] is put back into ! cem5t *uck1 z %[n at ,fig4 #agh1 except ?is "t ! top portion ( ! cyl9d] is all[$ to protrude s t we c turn ! top pivot & ! balance collet ,d1 ,fig4 #aga4 ,! sizes we h n[ to look to is to fit ! pivot z to ! top hole jewel 9 ! cock1 also ! hairspr+ seat ,d & balance seat ,d'4 ,^! are turn$ to diamet]s1 & are ! mo/ readily secur$ by ! use ( ! micromet] calip]s to be _h ( any l>ge wat*mak]s' tool & supply h\se4 ,9 addition to ! diamet]s nam$1 we mu/ get ! prop] height = ! balance1 :i* is repres5t$ by ! dott$ l9e b4 ,! measurem5t = ?is c usually be obta9$ f ! old cyl9d] by simply comp>+ x ) ! new "o z x re/s 9 ! cem5t *uck4 ,! true tool = su* measurem5ts is a height gage4 ,we h made no m5tion ( f9i%+ & poli%+ ! pivots1 z ^! po9ts are g5]ally well und]/ood by ! trade4 ,,remov+ ,,! ,,la! ,,cem5t4 ,"o po9t p]haps we might well say a few words on1 & ?is is 9 reg>d to remov+ ! la! cem5t4 ,su* cem5t is usually remov$ by boil+ 9 a copp] di% ) alcohol4 ,b !re are sev]al objections to ! practice4 ,9 ! fir/ place1 x wa/es a good deal ( alcohol1 & also leaves ! "w /a9$4 ,we c accompli% ?is op]ation quick]1 & save alcohol1 by putt+ ! cyl9d] ) ! wax on x 9 a v small homeopa?ic bottle & cork+ x tight4 ,! bottle is !n boil$ 9 wat]1 & 9 a few seconds ! %ellac is dissolv$ away4 ,! balance to mo/ cyl9d] wat*es is ( r$ brass1 & 9 "s in/ances ( l[ k>at gold2 9 ei!r case ! balance %\ld be repoli%$4 ,to d ?is dip 9 a /rong solution ( cyanide ( potassium dissolv$ 9 wat]2 "o-f\r? ounce ( cyanide 9 half p9t ( wat] is ab\t ! prop] /r5g?4 ,dip & r9se1 !n poli% ) a *amois buff & r\ge4 ,illu/ration3 ,fig4 #aha ,9 /ak+ on ! balance1 c>e %\ld be obs]v$ to set ! bank+ p9 9 ! rim s x w come "r2 ?is is usually secur$ by sett+ said p9 s x /&s opposite to ! op5+ 9 ! half %ell4 ,! seat ( ! balance on ! collet ,d %\ld be und]cut s t !re is only an edge to rivet d[n on ! balance4 ,?is w be bett] und]/ood by inspect+ ,fig4 #aha1 :]e we %[ a v]tical section ( ! collet ,d & cyl9d] ,a4 ,at g g is %[n ! und]cut edge ( ! balance seat1 :i* is fold$ ov] z ! balance is rivett$ fa/4 ,ab\t all t rema9s n[ to be done is to true up ! balance & br+ x to poise4 ,! practice frequ5tly adopt$ to poise a pla9 balance is to file x ) a half-r\nd file on ! inside1 9 ord] n to %[ any detraction :5 look+ at ! out] edge ( ! rim4 ,a bett] & quick] plan is to place ! balance 9 a split *uck1 & ) a diamond or r\nd-po9t$ tool scoop out a little piece ( metal z ! balance revolves4 ,9 do+ ?is1 ! sp9dle ( ! la! is turn$ by ! h& grasp+ ! pulley betwe5 ! f+] & ?umb4 ,! s-call$ diamond & r\nd-po9t$ tools are %[n at o o'1 ,fig4 #ahb4 ,! idea ( ?is plan ( r$uc+ ! weight ( a balance is1 "o ( ! tools o is re/$ on ! ,t-re/ & press$ =w>d until a *ip is />t$ & all[$ to ent] until suffici5t metal is engag$1 !n1 by sw++ d[n on ! h&le ( ! tool1 ! *ip is tak5 out4 ,illu/ration3 ,fig4 #ahb ,illu/ration3 ,fig4 #ahc ,9 plac+ a balance 9 a /ep *uck1 ! bank+ p9 is caus$ to ent] "o ( ! ?ree slots 9 ! *uck1 s z n to be b5t d[n on to ! rim ( ! balance4 ,x is seldom ! dep? betwe5 ! cyl9d] & escape :eel w ne$ be *ang$ aft] putt+ 9 a new cyl9d]2 if su* is ! case1 h[ev]1 move ! *>iot--we mean ! cock atta*$ to ! l[] plate4 ,d n attempt to *ange ! dep? by manipulat+ ! balance cock4 ,fig4 #ahc %[s1 at h h1 ! =m ( *ip tak5 out by ! tool o o'1 ,fig4 #ahb4 ,,index ,a ,acid fro/+1 #df ,action draw+s1 #ij ,action ( a *ronomet] escapem5t1 #adb ,act+ surface ( entrance lip1 #abg ,actions ( cyl9d] escapem5t1 #aab ,adhesion ( p>allel surfaces1 #id ,adju/able pallets1 #ih ,adju/+ screw = draw+ in/rum5ts1 #ba ,analysis ( pr9ciples involv$ 9 det5t1 #acg ,analysis ( ! action ( a lev] escapem5t1 #hf ,angle-measur+ device1 #fh ,angul> ext5t ( %ell ( cyl9d]1 #abb ,angul> motion1 draw+ an escapem5t to %[1 #ia ,h[ measur$1 #fi ,( escape :eel1 #cg ,antagoni/ic influ5ces1 #acc ,arc ( degrees1 #i ,atmosph]ic di/urbances1 #gd ,atta9m5t ( iso*ronism1 #aei ,b ,balance1 h[ x controls timekeep+1 #gc ,weight & in]tia (1 #acc ,balance spr+1 inv5tor (1 #acb ,bank+ slot ( cyl9d]1 #aab ,bank+s1 effect ( op5+ too wide1 #fc ,b> compasses1 #ba ,b>ometric pressure1 #gd ,basis = close measurem5ts1 #if ,c ,cem5t *uck1 h[ to use1 #agc ,*ronomet] det5t1 importance ( light con/ruction1 #acf ,*ronomet] escapem5t1 #aca1 #aee ,f\r pr9cipal p>ts (1 #acd ,circul> pallets1 #bg ,club-too? escapem5t1 #cj1 #cd ,club-too? lev] escapem5t ) circul> pallets & tang5tial lock+s1 #hc ,cr[n-:eel escapem5t1 #aee ,cyl9d]1 draw+ a1 #abj ,out] diamet] (1 #aaf ,putt+ 9 a new1 #afi ,cyl9d] escapem5t1 #aee ,date ( inv5tion1 etc41 #aaa ,=ms & proportions ( sev]al p>ts (1 #aaa ,names ( v>i\s p>ts1 #aab ,cyl9d] lips1 prop] %ape (1 #abd ,d ,dead-beat escapem5t1 #aca1 #ace ,only "o true1 #aab ,dep?1 betwe5 cyl9d] & escape :eel1 #abi ,effect ( *ang+1 #agf ,design+ a d\ble roll]1 #gg ,deta*$ escapem5t1 #aee ,det5t1 functions ( !1 #acg ,det5t escapem5t1 #aca1 #aee ,faults 91 #acb ,det5t spr+ dim5sions1 #ach ,det5t spr+s1 wid? (1 #adg ,dis*>g+ jewel1 sett+ !1 #adb ,dis*>g+ roll]1 #acf ,divid]s1 #i ,mak+1 #aj ,d\ble p5dulum1 #afj ,d\ble-roll] escapem5t1 #ge ,draw def9$1 #he ,draw+-bo>d1 #aa ,draw+ in/rum5ts1 #i ,draw+s1 advantage ( l>ge1 #bi ,drop & draw1 #aej ,duplex escapem5t1 #aca1 #aee ,e ,ela/icity ( spr+1 #acc ,engag+ friction1 #ha ,engli% recoil an*or1 #afg ,entrance lip ( cyl9d] escapem5t1 #abe ,escapem5t angles1 measur+1 #aja ,escapem5t error1 /udy (1 #fd ,escapem5t mat*+ tool1 #ajf ,escapem5t model1 #dj ,balance1 #db ,balance /aff1 #dd ,bridges1 #da1 #db ,escape :eel1 #dc ,extra balance cock1 #de ,fro/+1 #df ,hairspr+1 #db ,jewel =1 #dc ,l[] plate1 #da ,ma9 plate1 #da ,movem5t =1 #da ,pallet /aff1 #db ,pill>s1 #dc ,regulator1 #df ,uses (1 #dd ,wood base =1 #da ,escapem5ts comp>$1 #ajc ,escapem5t ( ,dut]tre1 #afj ,escape-:eel action1 #cj ,escape-:eel1 del9eat+ an1 #aa ,escape-:eel tee? vs4 cyl9d]1 #afi ,escape-:eel too? 9 action1 del9eat+ an1 #abf ,exit pallet1 #bf ,exp]im5ts ( ,galileo1 #aeh ,exp]im5ts ) a *ronomet]1 #adb ,ext5t ( angul> impulse1 #aah ,f ,fall def9$1 #ajf ,faults 9 ! det5t escapem5t1 #acb ,fix$ rules1 ( little value to /ud5t1 #acg ,flexure ( gold spr+1 #adf ,foot1 fitt+ up !1 #aea ,=k1 te/+ !1 #ga ,=k action1 #cj ,!ory (1 #ei ,=k & roll] action1 #ed ,=mulas = del9eat+ cyl9d] escapem5t1 #aae ,frictions1 #bd ,frictional escapem5t1 #aca1 #acb ,frictional surfaces1 #fc ,fusee1 #aca ,g ,gable escapem5t1 #afg ,gage1 a new1 #agb ,graham an*or escapem5t1 #aee ,gold spr+1 #adf ,gu>d po9t1 #gi ,mat]ial =1 #gi ,gummy secretion on impulse & dis*>g+ /ones1 #adg ,h ,heights 9 cyl9d]s1 h[ obta9$1 #aga ,hole jewels1 di/ance ap>t1 #adj ,i ,imag9>y faults 9 cyl9d]s1 #abi ,impulse angle1 #aah ,impulse arc1 ext5t (1 #acd ,impulse jewel set oblique1 #adg ,impulse planes1 locat+ out] angle (1 #ci ,impulse roll]1 #acf ,incl9e ( tee?1 #abb ,in]tia ( balance1 #acc ,inv5tions ( ,b]?\d1 #afc ,b?une1 #afe ,clem5t1 #aff ,dr4 ,hook1 #afb ,h>rison1 #afa ,hautefeuille1 #afa ,huyg5s1 #aeh ,l]oy1 #afc ,?i\t1 #afe ,j ,jewel p91 det]m9+ size1 #eh ,cem5t+ 91 #fg ,sett+s1 #ff ,jewel-p9 sett]s1 #fg ,l ,la! cem5t1 #agc ,remov+1 #age ,lev]1 prop] l5g? (1 #fa ,lev] =k1 horn (1 #fa prongs (1 #fj ,lift1 real & app>5t1 #aab ,lift+ angle1 #aad ,lock1 am\nt (1 #bh ,def9$1 #he ,lock & drop te/+1 #fi ,lock+ jewel1 mov+ !1 #adi ,lock+ /one1 good =m (1 #add ,l[] plate1 circul> op5+ 91 #ef ,m ,m>9e *ronomet]1 numb] ( beats to h\r1 #adh ,ma!matics1 #ie ,measur+ tools1 #aga ,metal draw+s1 advantages (1 #adj ,motion1 h[ obta9$1 #af ,movem5t hold]1 #aaj ,n ,neutral lock+s1 #hd ,o ,orig9al design+1 #adh ,p ,pallet action1 locat+ !1 #ij ,pallet-&-=k action1 #ab1 #ac1 #ag1 #ah ,pallet /ones1 h[ to set1 #ajd ,pallets1 adju/+ to mat* ! =k1 #fe ,pap] = draw+1 #aa ,p>ts1 relations ( !1 #cb ,pass+ holl[1 #fb ,p]fect$ lev] escapem5t1 #hg ,pivots1 turn+1 #agb ,po9t ( p]cussion1 #aci ,po9ts = draw+ in/rum5ts1 #bj ,poli%+ mat]ials1 #eb ,p[] leaks1 #af ,p[] lo/ 9 lev] escapem5t1 #hg ,practical problems 9 ! lev] escapem5t1 #ih ,r ,radial ext5t ( outside ( cyl9d]1 #abe ,rat*et-too? escape :eel1 #ab ,recoil an*or escapem5t1 #aee ,recoil escapem5t1 #aed ,r$uc$ gable escapem5t1 #afg ,retrograde motion1 #cf ,roll] action1 :y #cj degrees1 #ee ,( d\ble roll]1 #gh ,roll] diamet]1 det]m9+ !1 #ee ,rul+ p51 #i ,s ,safety action1 #ef ,scale ( in*es1 #i ,screws1 mak+ extra l>ge1 #de ,scre:eads1 fancy1 #de ,select+ new cyl9d]1 #agj ,%ap+1 advantages ga9$ 91 #aaf ,%eet /eel1 cutt+1 #dh ,%ort =k1 #ajj ,s\nd z indicator ( correct action1 #add ,spr+1 ela/icity (1 #acc ,/ak+ on a balance1 #age ,/eel1 poli%+1 #di ,temp]+1 #di ,/udy draw+s1 #abd ,sy/ems ( measurem5ts1 #aad ,t ,tang5tial lock+s1 #hj1 #adh ,te/ gage = angul> movem5t1 #fe ,!oretical action ( d\ble roll]1 #gf ,timekeep+1 controll$ by balance1 #gc ,tool = l5g? measurem5t1 #agd ,tools1 measur+1 #aga ,triangle1 #ah ,t-squ>e1 #i ,u ,unlock+ action1 #ef ,unlock+ roll]1 #acf ,v ,v]ge escapem5t1 #aca1 #aee ,w ,weight & in]tia ( balance1 #acc ,work+ model ( cyl9d] escapem5t1 #abc 99 99 99 99 99 99 ,,! ,,wat* ,,adju/]',s ,,manual ,illu/ration ,a ,complete & ,practical ,guide = ,wat*mak]s 9 ,adju/+ ,wat*es & ,*ronomet]s = ,iso*ronism1 ,position1 ,heat & ,cold4 ,,by ,,*>les ,,edg> ,,fritts 7,,excelsior71 ,au?or ( ,practical ,h9ts on ,wat* ,repair+1 ,practical ,treatise on ,balance ,spr+1 ,electricity & ,magnetism = ,wat*mak]s1 etc41 etc4 ,?is well-kn[n "w is n[ recogniz$ z ! /&>d au?ority on ! adju/m5ts & k9dr$ subjects1 bo? "h & 9 ,engl&4 ,x conta9s an exhau/ive consid]ation ( ! v>i\s !ories propos$1 ! me*anical pr9ciples on :i* ! adju/m5ts are bas$1 & ! diff]5t me?ods foll[$ 9 actual practice1 giv+ all t is publicly kn[n 9 ! trade1 ) a l>ge am\nt ( entirely new practical matt] n to be f\nd else:]e1 obta9$ f ! be/ manufactur]s & workm51 z well z f ! au?or's own /udies & exp]i5ces4 ,s5t po/paid to any "p ( ! _w on receipt ( #b4ej 7#ajs4 #e;d47 ,,! ,,key/one 7,,sole ,,ag5t71 #ai,,? ,,& ,,br[n ,,/reets1 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,art ,,( ,,engrav+ ,illu/ration ,a ,complete ,treatise on ! ,engrav]'s ,art1 ) ,special ,ref]5ce to ,lett] & ,monogram ,engrav+4 ,specially ,compil$ z a ,/&>d ,text-,book = ,/ud5ts & a ,reliable ,ref]5ce ,book = ,engrav]s4 ,?is "w is ! only ?or\ghly reliable & exhau/ive treatise publi%$ on ?is important subject4 ,x is an ideal text-book1 beg9n+ ) ! rudim5ts & lead+ ! /ud5t /ep by /ep to a complete & practical ma/]y ( ! art4 ,back ( ! au?or%ip is a long exp]i5ce z a successful engrav]1 also a successful c>e] z an in/ructor 9 engrav+4 ,^! qualifications ensure accuracy & reliability ( matt]1 & su* a c\rse ( in/ruction z is be/ = ! le>n] & qualifi$ engrav]4 ,! mo/ notable feature ( ! new treatise is ! in/ructive "* ( ! illu/rations4 ,!re are ov] #bjj orig9al illu/rations by ! au?or4 ,a v complete index facilitates ref]5ce to any requir$ topic4 ,b\nd 9 ,silk ,clo?--#bjh ,pages & #baf ,illu/rations4 ,s5t po/paid to any "p ( ! _w on receipt ( price1 #a4ej 7#fs4 #c;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,key/one ,,portfolio ,,( ,,monograms ,illu/ration3 ,c4,b4,r4 ,illu/ration3 ,a4,o4,u4,w ,illu/ration3 ,i4,r4,c4 ,illu/ration3 ,g4,h4,i4 ,?is portfolio conta9s #aba comb9ation designs4 ,^! designs 7 select$ f ! be/ ( ^? submitt$ 9 a prize competition held by ,! ,key/one1 & w be f\nd ( value to e "o do+ engrav+4 ,! designs are conc$$ to be ! be/ 9 ! m>ket1 excell+ 9 art & novelty ( comb9ation & skill 9 execution4 ,!y are pr9t$ f /eel plates on /iff1 durable pap]1 & conta9 sample monograms 9 a v>iety ( comb9ations4 ,! portfolio is a b5* requirem5t t no jewel] c af=d to be )\t4 ,x is a necess>y supplem5t to any text-book on lett] engrav+4 ,price1 #ej ,c5ts 7#bs47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,optician',s ,,manual ,,vol4 ,i4 ,,by ,c4,h4 ,,br[n1 ,m4,d4 ,graduate ,univ]sity ( ,p5nsylvania2 ,pr(essor ( ,optics & ,refraction2 =m]ly ,physician 9 ,philadelphia ,hospital2 ,memb] ( ,philadelphia ,c\nty1 ,p5nsylvania ,/ate & ,am]ican ,m$ical ,societies4 ,illu/ration ,! ,optician's ,manual1 ,vol4 ,i41 has prov$ to be ! mo/ popul> "w on practical refraction ev] publi%$4 ,! k x conta9s has be5 m effective 9 build+ up ! optical pr(ession ?an any o!r educational factor4 ,a /udy ( x is ess5tial to an intellig5t appreciation ( ,vol4 ,,ii41 = x lays ! f\ndation /ructure ( all optical k1 z ! titles ( its t5 *apt]s %[3 ,*apt] ,i4--,introductory ,rem>ks4 ,*apt] ,,ii4--,! ,eye ,anatomically4 ,*apt] ,,iii4--,! ,eye ,optically2 or1 ,! ,physiology ( ,vision4 ,*apt] ,,iv4--,optics4 ,*apt] ,v4--,l5ses4 ,*apt] ,,vi4--,numb]+ ( ,l5ses4 ,*apt] ,,vii4--,! ,use & ,value ( ,glasses4 ,*apt] ,,viii4--,outfit ,requir$4 ,*apt] ,,ix4--,me?od ( ,exam9ation4 ,*apt] ,x4--,presbyopia4 ,! ,optician's ,manual1 ,vol4 ,i41 is complete 9 itself1 & has be5 ! entire optical education ( _m successful opticians4 ,= /ud5t & tea*] x is ! be/ treatise ( its k9d1 be+ simple 9 /yle1 accurate 9 /atem5t & compreh5sive 9 its treatm5t ( refractive proc$ure & problems4 ,x m]its ! place ( honor beside ,vol4 ,,ii4 9 e optical libr>y4 ,b\nd 9 ,clo?--#dbb pages--color$ plates & ,illu/rations4 ,s5t po/paid on receipt ( #b4jj 7#hs4 #d;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,optician',s ,,manual ,,vol4 ,,ii4 ,,by ,c4,h4 ,,br[n1 ,m4,d4 ,graduate ,univ]sity ( ,p5nsylvania2 ,pr(essor ( ,optics & ,refraction2 =m]ly ,physician 9 ,philadelphia ,hospital2 ,memb] ( ,philadelphia ,c\nty1 ,p5nsylvania ,/ate & ,am]ican ,m$ical ,societies4 ,illu/ration ,! ,optician's ,manual1 ,vol4 ,,ii41 is a direct cont9uation ( ,! ,optician's ,manual1 ,vol4 ,i41 be+ a mu* m advanc$ & compreh5sive treatise4 ,x cov]s 9 m9ute/ detail ! f\r great subdivisions ( practical eye refraction1 viz3 ,myopia4 ,hyp]metropia4 ,a/igmatism4 ,muscul> ,anomalies4 ,x conta9s ! mo/ au?oritative & complete rese>*es up to date on ^! subjects1 treat$ by ! ma/] h& ( an em95t oculi/ & optical tea*]4 ,x is ?or\ghly practical1 explicit 9 /atem5t & accurate z to fact4 ,all refractive errors & complications are cle>ly expla9$1 & ! me?ods ( correction ?or\ghly elucidat$4 ,?is book fills ! la/ great want 9 high] refractive optics1 & ! k conta9$ 9 x m>ks ! /&>d ( pr(essionalism4 ,b\nd 9 ,clo?--#djh pages--) illu/rations4 ,s5t po/paid on receipt ( #b4jj 7#hs4 #d;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,skiascopy ,,& ,,! ,,use ,,( ,,! ,,ret9oscope ,illu/ration ,a ,treatise on ! ,%ad[ ,te/ 9 its ,practical ,application to ! ,"w ( ,refraction1 ) an ,explanation 9 ,detail ( ! ,optical ,pr9ciples on :i* ! ,sci5ce is ,bas$4 ,?is new "w1 ! sale ( :i* has already necessitat$ a second edition1 f> excels all previ\s treatises on ! subject 9 compreh5siv5ess & practical value to ! refractioni/4 ,x n only expla9s ! te/1 b exp\nds fully & explicitly ! pr9ciples und]ly+ x--n only ! ph5om5a reveal$ by ! te/1 b ! :y & :]e=e ( su* ph5om5a4 ,x conta9s a full description ( skiascopic app>atus1 includ+ ! late/ & mo/ approv$ in/rum5ts4 ,9 dep? ( rese>*1 weal? ( illu/ration & sci5tific complet5ess ?is "w is unique4 ,b\nd 9 clo?2 conta9s #bca pages & #gc illu/rations & color$ plates4 ,s5t po/paid to any "p ( ! _w on receipt ( #a4jj 7#ds4 #b;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,& ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,physiologic ,,optics ,ocul> ,dioptrics--,functions ( ! ,ret9a--,ocul> ,movem5ts & ,b9ocul> ,vision ,,by ,,dr4 ,m4 ,,ts*]n+ ,adjunct-,director ( ! ,laboratory ( ,oph?almology at ! ,sorbonne1 ,p>is ,,au?oriz$ ,,translation ,,by ,,c>l ,,weil&1 ,m4,d4 ,=m] ,*ief ( ,cl9ic 9 ! ,eye ,dep>tm5t ( ! ,jeff]son ,college ,hospital1 ,philadelphia1 ,pa4 ,?is is ! cr[n+ "w on physiologic optics1 & w m>k a new era 9 optical /udy4 ,its di/+ui%$ au?or is recogniz$ 9 ! _w ( sci5ce z ! greate/ liv+ au?ority on ?is subject1 & 8 book embodies n only 8 own rese>*es1 b ^? ( ! sev]al hundr$ inve/igators :o1 9 ! pa/ hundr$ ye>s1 made ! eye _! specialty & life /udy4 ,ts*]n+ has sift$ ! gold ( all optical rese>* f ! dross1 & 8 book1 z n[ publi%$ 9 ,engli% ) _m additions1 is ! mo/ valuable m9e ( reliable optical k )9 rea* ( oph?almologi/s4 ,x conta9s #chj pages & #bab illu/rations1 & its ref]5ce li/ comprises ! entire galaxy ( sci5ti/s :o h made ! c5tury fam\s 9 ! _w ( optics4 ,! *apt]s on ,oph?almometry1 ,oph?almoscopy1 ,accommodation1 ,a/igmatism1 ,ab]ration & ,entoptic ,ph5om5a1 etc4--9 fact1 ! entire book conta9s s mu* t is new1 practical & necess>y t no refractioni/ c af=d to be )\t x4 ,b\nd 9 ,clo?4 #chj ,pages1 #bab ,illu/rations4 ,price1 #c4ej 7#ads4 #g;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,oph?almic ,,l5ses ,dioptric ,=mul = ,comb9$ ,cyl9drical ,l5ses1 ,! ,prism-,dioptry & ,o!r ,orig9al ,pap]s ,,by ,,*>les ,f4 ,,pr5tice1 ,m4,e4 ,a new & revis$ edition ( all ! orig9al pap]s ( ?is not$ au?or1 comb9$ 9 "o volume4 ,9 ?is revis$ =m1 ) ! addition ( rec5t rese>*1 ^! /&>d pap]s are ( increas$ value4 ,comb9$ = ! fir/ "t 9 "o volume1 !y are ! greate/ compilation on ! subject ( l5ses extant4 ,?is book ( ov] #bjj pages conta9s ! foll[+ pap]s3 ,oph?almic ,l5ses4 ,dioptric ,=mul = ,comb9$ ,cyl9drical ,l5ses4 ,! ,prism-,dioptry4 ,a ,metric ,sy/em ( ,numb]+ & ,measur+ ,prisms4 ,! ,relation ( ! ,prism-,dioptry to ! ,met] ,angle4 ,! ,relation ( ! ,prism-,dioptry to ! ,l5s-,dioptry4 ,! ,p]fect$ ,prismomet]4 ,! ,prismometric ,scale4 ,on ! ,practical ,execution ( ,oph?almic ,prescriptions involv+ ,prisms4 ,a ,problem 9 ,cem5t$ ,bi-,focal ,l5ses1 ,solv$ by ! ,prism-,dioptry4 ,:y ,/rong ,contra-,g5]ic ,l5ses ( ,equal ,p[] ,fail to ,neutralize ,ea* ,o!r4 ,! ,advantages ( ! ,sph]o-,toric ,l5s4 ,! ,iris1 z ,diaphragm & ,photo/at4 ,! ,typoscope4 ,! ,correction ( ,deplet$ ,dynamic ,refraction 7,presbyopia74 ,press ,notices on ! ,orig9al ,edition3 ,,oph?almic ,,l5ses4 ,! "w /&s alone1 9 its pres5t =m1 a comp5dium ( ! v>i\s laws ( physics relative to ?is subject t are s difficult ( access 9 scatt]$ treatises4--,new ,engl& ,m$ical ,gazette4 ,x is ! mo/ complete & be/ illu/rat$ book on ?is special subject ev] publi%$4--,horological ,review1 ,new ,york4 ,( all ! simple treatises on ! prop]ties ( l5ses t we h se51 ?is is incomp>ably ! be/4444 ,! tea*] ( ! av]age m$ical /ud5t w hail ?is little "w z a great boon4--,ar*ives ( ,oph?almology1 edit$ by ,h4 ,knapp1 ,m4,d4 ,,dioptric ,,=mul ,,= ,,comb9$ ,,cyl9drical ,,l5ses4 ,?is little bro*ure solves ! problem ( comb9$ cyl9d]s 9 all its aspects1 & 9 a mann] simple en\gh = ! compreh5sion ( ! av]age /ud5t ( oph?almology4 ,! au?or is to be congratulat$ ^u ! success t has cr[n$ 8 labors1 = n[h]e is !re to be f\nd s simple & yet s complete an explanation z is conta9$ 9 ^! pages4--,ar*ives ( ,oph?almology1 edit$ by ,h4 ,knapp1 ,m4,d4 ,?is exhau/ive "w ( ,mr4 ,pr5tice is a solution ( "o ( ! mo/ difficult problems 9 oph?almological optics4 ,?anks are due to ,mr4 ,pr5tice = ! excell5t mann] 9 :i* he has elucidat$ a subject :i* has n hi!rto be5 satisfactorily expla9$4--,! ,oph?almic ,review1 ,london4 ,! book conta9s #aaj ,orig9al ,diagrams4 ,b\nd 9 clo?4 ,price1 #a4ej 7#fs4 #c;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,optometric ,,record ,,book ,a record book1 :]e9 to record optometric exam9ations1 is an indisp5sable adjunct ( an optician's outfit4 ,! ,key/one ,optometric ,record ,book 0 specially prep>$ = ?is purpose4 ,x excels all o!rs 9 be+ n only a record book1 b an invaluable guide 9 exam9ation4 ,! book conta9s two hundr$ record =ms ) pr9t$ head+s1 sugge/+1 9 ! prop] ord]1 ! c\rse ( exam9ation t %\ld be pursu$ to obta9 mo/ accurate results4 ,ea* book has an index1 :i* enables ! optician to ref] in/antly to ! case ( any p>ticul> pati5t4 ,! ,key/one ,record ,book dim9i%es ! "t & labor requir$ = exam9ations1 obviates possible ov]sights f c>elessness & assures a sy/ematic & ?or\gh exam9ation ( ! eye1 z well z furni%es a p]man5t record ( all exam9ations4 ,s5t po/paid on receipt ( #a4jj 7#ds4 #b;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,key/one ,,book ,,( ,,monograms ,?is book conta9s #bdjj designs & ov] #fjjj diff]5t comb9ations ( two & ?ree lett]s4 ,is an ess5tial to e jewel]'s outfit4 ,x is n only necess>y = ! jewel]'s own use & guidance1 b also to enable cu/om]s to indicate exactly :at !y want1 ?us sav+ "t & possible dissatisfaction4 ,! ,monograms are purposely left 9 outl9e1 9 ord] to %[ cle>ly h[ ! lett]s are int]tw9$ or wov5 toge!r4 ,?is p]mits su* enl>gem5t or r$uction ( ! ,monogram z may be desir$1 & z mu* %ad+1 ornam5tation & arti/ic f9i% z ! jewel] may wi% to add4 ,?is compreh5sive compilation ( ,monograms is especially available z a ref]5ce book 9 busy seasons4 ,its use saves "t1 ?\ght & labor1 & ensures quick & satisfactory "w4 ,monograms are ! fad ( ! "t1 & !re's money = ! jewel] 9 ,monogram engrav+4 ,! k 9 ?is book c be turn$ into ca%4 ,all ! v>i\s /yles ( lett]s are illu/rat$4 ,price1 #a4jj 7#ds4 #b;d47 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,key/one ,,record ,,book ,,( ,,wat* ,,repairs ,?is book is #i #aa in*es1 has #abj pages1 & space = record+ sixte5 hundr$ jobs 9 detail4 ,x is made ( l95 l$g] pap]1 b\nd 9 clo? ) lea!r back & corn]s4 ,price1 #a4jj 7#ds4 #b;d471 prepaid4 ,no o!r record book on ! m>ket is s complete1 & all co/ m4 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4 99 99 99 99 99 ,,! ,,key/one ,,book ,,( ,,gu>antees ,,( ,,wat* ,,repairs ,?is book conta9s two hundr$ pr9t$ gu>antees1 & is h&somely b\nd4 ,ea* gu>antee is #c #g in*es1 & mo/ c>efully word$4 ,jewel]s h discov]$ t ! use ( ^! gu>antees is a mo/ effective way to secure & cultivate public confid5ce4 ,we sell a book ( two hundr$ = #a4jj 7#ds4 #b;d471 prepaid1 :i* is "o-?ird less ?an ! price *>g$ by o!rs = a simil> book4 ,,publi%$ ,,by ,,! ,,key/one1 ,,! ,,organ ,,( ,,! ,,jewelry ,,& ,,optical ,,trades1 #ai,,? ,,br[n ,,/s41 ,,philadelphia1 ,u4,s4,a4