,,light ,,& ,,col\r ,,!ories ,illu/ration3 ,,t9tomet]4 ,=m ( ,in/rum5t = ,opaque ,obs]vation4 ,illu/ration3 ,reproductions ( "s ,m$als aw>d$ to ,,joseph ,w4 ,,lovibond',s ,me?od ( ,col\r ,analysis ,,= ,sci5tific & ,comm]cial ,purposes4 ,,light ,,& ,,col\r ,,!ories & _! ,relation to ,light & ,col\r ,/&>dization ,by ,,joseph ,w4 ,,lovibond ,,illu/rat$ ,,by #aa ,,plates ,,col\r$ ,,by ,,h& ,illu/ration3 ,logo ,london ,e4 ,f4 ,n4 ,,spon1 ,limit$1 #eg ,,haym>ket ,new ,york ,,spon ,,*amb]la91 #abc ,,lib]ty ,,/reet #aiae ,,cont5ts ,,page ,li/ ( ,plates vii ,purpose ix ,,*apt] ,i4 ,introduction #a ,,*apt] ,,ii4 ,evolution ( ! ,me?od #e ,,*apt] ,,iii4 ,evolution ( ! ,unit #i ,,*apt] ,,iv4 ,d]ivation ( ,col\r f ,:ite ,light #aa ,,*apt] ,v4 ,/&>d ,:ite ,light #ad ,,*apt] ,,vi4 ,qualitative ,col\r ,nom5clature #ag ,,*apt] ,,vii4 ,quantitative ,col\r ,nom5clature ,,*apt] ,,viii4 ,! ,col\r ,scales #bh ,,*apt] ,,ix4 ,col\r ,*>ts #ca ,,*apt] ,x4 ,repres5tations ( ,col\r 9 ,space ( ,?ree ,dim5sions #cd ,,*apt] ,,xi4 ,! ,spectrum 9 relation to ,col\r ,/&>dization #cf ,,*apt] ,,xii4 ,! ,physiological ,light ,unit #de ,,app5dix ,i4 ,col\r ,education #ei ,,app5dix ,,ii4 ,! ,possibilities ( a ,/&>d ,light & ,col\r ,unit #fi ,,app5dix ,,iii4 ,dr4 ,dudley ,corbett's ,radiomet] #hc ,index #hi ,,errata4 ,plate ,i4 ,newton's ,!ory4 ,! ,indigo l9e is errone\sly plac$ betwe5 ! ,violet & ! ,r$2 x %\ld be betwe5 ! ,blue & ! ,violet4 ,page #dj4--;,fif? l9e f ! bottom1 = ,fraunhop] read ,fraunh(]4 ,to face p4 vi41 ,lovibond1 ,light & ,col\r ,!ories4 ,p4,r4 #acag ,,li/ ,,( ,,plates ,,to ,,face ,,page ,plate ,i4 ,six ,col\r ,!ories #d ,,ii4 ,circles ,illu/rat+ ,absorption ( ,:ite ,light #aa ,,iii4 ,diagram ,illu/rat+ ,analysis ( ,:ite ,light #ac ,,iv4 ,fir/ ,sy/em ( ,*>t+ ,col\r #ca ,v4 ,second ,sy/em ( ,*>t+ ,col\r #cc ,,vi4 ,six ,t9tometrical ,col\r ,*>ts #ci ,,vii4 ,two ,circles #dj ,,viii4 ,absorption ,curves ( ,dyes #gf ,,ix4 ,fad+ ,curves ( ,dyes #gh ,x4 ,comp>ison ,curves ( ,heal?y & ,diseas$ ,blood #hj ,,xi4 ,specific ,col\r ,curves ( ,heal?y & ,diseas$ ,human ,blood #hb ,,purpose ,! purpose ( ?is "w is to demon/rate t col\r is a det]m9able prop]ty ( matt]1 & to make g5]ally kn[n me?ods ( col\r analysis & syn!sis :i* h prov$ ( great practical value 9 e/abli%+ /&>ds ( purity 9 "s indu/ries4 ,! purpose is also to %[ t ! me?ods are ?or\ghly sci5tific 9 !ory & practice1 & t ! results are n likely to be *ang$ by fur!r discov]ies4 ,also t out ( ! "w done a new law has be5 develop$1 :i* ! writ] calls ! ,law ( ,specific ,col\r ,developm5t1 mean+ t e sub/ance has its own rate ( col\r developm5t = regul>ly increas+ ?icknesses4 ,,! ,,!ory4 ,( ! six col\rs 9 :ite light--r$1 orange1 yell[1 gre51 blue & violet2 ,r$1 ,yell[ & ,blue are reg>d$ z dom9ants1 because !y visually hold ! associat$ col\rs orange1 gre5 & violet 9 subjection4 ,an equival5t unit ( pure r$1 pure yell[ & pure blue is adopt$1 & incorporat$ into glass4 ,! unit is multipli$ to obta9 great] int5sities1 & divid$ to obta9 less] int5sities4 ,! col\r$ glasses are call$ absorb5ts4 ,! r$ absorb5t transmits violet1 r$ & orange1 b ! r$ ray alone is visible z col\r1 until ! o!r absorb5ts are sup]impos$1 & ! "* ( ! gr\p ( rays *ang$4 ,9 ! same way yell[ transmits orange & gre51 & blue transmits gre5 & violet1 :il/ ! yell[ & blue alone are visible z col\r4 ,orange1 gre5 & violet are "h call$ subord9ates1 :i* may be develop$ z foll[s3-- ,or4 ,r4 ,y4 ,gr4 ,y4 ,b4 ,vi4 ,b4 ,r4 ,tw5ty-five ye>s' exp]i5ce 9 ! application ( ! !ory & ! me?od to ! requirem5ts ( practical "w1 h giv5 no reason = *ange4 ,foll[+ w be f\nd a li/ ( aw>ds f ,int]national ,juries & ,sci5tific ,societies1 also a li/ ( indu/ries 9 :i* ! writ]'s me?od is giv+ entire satisfaction4 ,aw>ds by ,int]national ,juries4 ,/4 ,l\is #a ,silv] ,m$al4 #b ,bronze ,m$als4 ,brussels #a ,gold ,m$al4 #c ,silv] ,m$als4 ,tur9 ,diploma ( ,hon\r4 #a ,gold ,m$al4 #a ,silv] ,m$al4 ,aw>ds by ,sci5tific ,societies4 ,sanit>y ,in/itute ( ,great ,brita9-- ,bronze ,m$al = ,col\rometrical ,wat] ,analysis4 ,royal ,sanit>y ,in/itute-- ,bronze ,m$al = ,measur+ ,smoke ,d5sities4 ,int]national ,congress on ,s*ool ,hygi5e-- ,bronze ,m$al = ,col\r ,educator4 ,royal ,sanit>y ,in/itute-- ,silv] ,m$al = ,col\r ,educator4 ,smoke ,abatem5t ,society1 ,%effield-- ,diploma = ,sy/em ( ,col\r ,measurem5t4 ,royal ,sanit>y ,in/itute-- ,bronze ,m$al = ,quantitative ,e/imation ( ,col\r ,bl9dness4 ,franco-,briti% ,exhibition-- ,gold ,m$al = ,col\r ,educator4 ,int]national ,m$ical ,congress-- ,bronze ,m$al = ,t9tomet] z ,m$ical requisite4 ,royal ,sanit>y ,in/itute-- ,silv] ,m$al = rec5t developm5ts4 ,royal ,sanit>y ,in/itute-- ,silv] ,m$al ,corbett's ,radiomet]4 ,=mal ,adoption ( ,t9tomet] ,/&>ds by-- ,! ,petroleum ,indu/ry4 ,! ,massa*usetts ,bo>d ( ,heal?4 ,! ,int]national ,association ( ,lea!r ,trades ,*emi/s4 ,! ,int]-/ates ,cotton ,se$ ,oil ,association4 ,! ,bureau ( ,engrav+ & ,pr9t+1 ,*9a4 ,9 g5]al use by ! foll[+ ,indu/ries-- ,brew+ & ,malt+4 ,tann+4 ,w9e & ,_s ,m]*ants4 ,dye+ & ,pr9t+4 ,pa9t1 ,oil & ,v>ni% ,m]*ants4 ,mill]s4 ,wat] ,works ,*emi/s4 ,c]amic ,works4 ,= e/imat+ p] c5t4 ( ,c>bon 9 ,/eel4 ,= e/imat+ p] c5t4 ( ,ammonia4 ,= e/imat+ ,col\rs = ,an?ropological ,classifications4 ,= e/imat+ ,smoke ,d5sities4 ,= e/imat+ ,haemoglob9 9 ! ,blood4 ,= e/imat+ ,col\r ( ,:ale ,oil1 etc41 etc4 ,,! ,,me?od4 ,! col\r composition ( any object may be measur$ by sup]impos+ units ( diff]5t col\rs until ! col\r ( ! object is mat*$4 ,a conv5i5t app>atus is furni%$ = ?is purpose4 ,! composition ( ! col\r is le>n$ by m]ely read+ ! m>k+s on ! glasses4 ,x is ( c\rse necess>y t 9 ! isolation ( col\r rays1 "s unit = measur+ ! int5sity ( bo? light & col\r be e/abli%$4 ,z w be expla9$ lat]1 all su* units are necess>ily arbitr>y4 ,9 ?is me?od ! unit has be5 e/abli%$ by tak+ ! smalle/ am\nt ( col\r easily p]ceptible to ! ord9>y vision4 ,?is unit or 8"o0 is divid$ into t5?s 9 ! d>k] %ades1 & hundr$?s 9 ! light] scale4 ,"o "o-hundr$? is ! smalle/ am\nt ( col\r measurable by a normal tra9$ vision4 ,:5 equival5t units 9 ! ?ree col\rs are sup]impos$1 _! equival5t value 7n _! aggregate value7 repres5ts s mu* :ite light absorb$4 ,= in/ance1 #b ,r4 #b ,y4 #b ,b4 absorbs two units ( :ite light4 ,:5 ! absorptive p[] ( ! col\r /&>ds is less ?an ! int5sity ( ! light1 associat$ :ite light rema9s4 ,,joseph ,w4 ,,lovibond4 ,! ,col\r ,laboratories1 ,salisbury4 ,decemb]1 #aiad4 ,light & ,col\r ,!ories ,,*apt] ,i4 ,introduction4 ,x may at fir/ appe> /range t col\r1 "o ( ! mo/ important indices ( value 9 ! ,arts1 ,manufactures1 & ,natural ,products1 %\ld h no common nom5clature or reliable /&>d = ref]5ce1 ! reproduction ( a giv5 col\r dep5d+ = exactitude on ! memory ( a s5sation2 :]eas ?is bran* ( sci5ce requires a physical means ( record+ a col\r1 ) a p[] ( recov]y4 ,x rema9s to be %[n t ?is p[] ( record & recov]y is possible1 & dep5ds only on ! obs]vance ( a few simple natural laws easy ( application4 ,! /udy ( col\r is c>ri$ on by two pr9cipal me?ods3 ! spectroscopic1 :]e ! col\rs are p>tially sep>at$ z a cont9u\s b& by a regul> v>iation 9 _! indices ( refraction1 ! col\rs gradually m]g+ into ea* o!r by ov]lapp+ 9 opposite directions2 or by absorption1 :]e a col\r is develop$ by absorb+ its complem5t>y1 & is isolat$ z a s+le or complex col\r4 ,?is latt] is nature's own me?od4 ,x is necess>y to t\* on "s !oretical diff]5ces :i* exi/ betwe5 ,sci5ti/s & ,arti/s1 z to :i* are ,prim>y col\rs1 z confusion ( ?is "* ret>ds inve/igation4 ,sci5ti/s adopt ,r$1 ,gre51 & ,violet z ,prim>ies1 reg>d+ all o!r col\rs z mixtures ( ^!2 :il/ ,arti/s & ,col\ri/s adopt ,r$1 ,yell[ & ,blue z ! ,prim>ies1 & all o!r col\rs z made f !m4 ,! !ory ( ! ,sci5ti/s is bas$ on ! ph5om5a develop$ by mix+ col\r$ lights tak5 f diff]5t p>ts ( ! spectrum4 ,?is is a me?od ( syn!sis1 ea* add$ col\r be+ a progressive /age t[>ds ! complexity ( :ite light4 ,9 ?is case ! col\r develop$ is t ( ! prepond]at+ ray ( a complex beam4 ,! !ory ( ! ,arti/s is bas$ on ! ph5om5a develop$ by mix$ pigm5ts4 ,?is is a me?od ( analysis1 t5d+ t[>ds ray simplicity1 ea* add$ pigm5t r$uc+ ! complexity ( ! col\r develop$ by its p[] ( selective absorption4 ,! !oretical diff]5ces betwe5 ! two s*ools appe> to h aris5 f suppos+ t a giv5 col\r develop$ by ! two me?ods %\ld correspond2 b consid]+ ! diff]5ces 9 _! ray composition1 ?is w\ld be impossible1 = al?\gh bo? may be describable by "o g5]al col\r t]m1 z = in/ance a ,r$1 !y w\ld be ( two v>ieties4 ,x rema9s to be %[n t "o !ory may cov] bo? sets ( ph5om5a4 ,! ,r$1 ,gre51 & ,violet !ory appe>s to be bas$ on two pr9cipal assumptions3 fir/ t !re are only ?ree fundam5tal col\rs2 & second t ! rays tak5 f diff]5t col\r areas are pure col\rs4 ,bo? assumptions are op5 to "q4 ,9 reg>d to ! fir/1 !re is no difficulty 9 isolat+ six col\rs2 & z to ! second1 x c be demon/rat$ t ! col\rs d ov]lap 9 e "p1 ) a d\ble ov]lapp+ 9 ! middle col\rs1 & are !re=e n simple b complex4 ,,pa/ ,,!ories4 ,9 a "w ( ?is nature x is unnecess>y to deal m9utely ) ! !ories :i* h be5 adopt$ f "t to "t s9ce ,newton's discov]y ( ! cont9u\s spectrum4 ,x w1 h[ev]1 be useful to t\* on ! pr9cipal po9ts :]e !ori/s are agre$1 & also on "s ( _! po9ts ( diff]5ce1 ! latt] 9 ord] to f9d1 if possible1 ! causes ( _! diff]5ce4 ,,table ,i4 ---------------------------------------- ------------------------------ ,no4 ( ,prim>y ,col\rs4 ,rays4 ---------------------------------------- ------------------------------ ,newton 7lat]7 #g ,r$1 ,orange1 ,yell[1 ,gre51 ,blue1 ,indigo1 ,violet ,w]n] #f ,r$1 ,orange1 ,yell[1 ,gre51 ,blue1 ,violet ,newton & ,helmholtz #e ,r$1 ,yell[1 ,gre51 ,blue1 ,violet 7e>ly7 ,h]+ #d ,r$1 ,yell[1 ,gre51 ,blue ,*evieul1 ,brew/]1 ,hay1 ,r$grave1 ,field #c ,r$1 ,yell[1 ,blue ,"y1 ,helmholtz 7lat]7 #c ,r$1 ,gre51 ,violet ---------------------------------------- ------------------------------ ,note to ,plate ,i4 ,! respective positions ( ! prim>ies ( ea* !ory 9 reg>d to ! :ole cycle ( di/+ui%able col\rs are illu/rat$ above1 & ! prim>ies ( ea* !ory are %[n 9 _! sev]al spectrum positions1 ! spectrum be+ %[n z b5t 9 circul> =m4 ,! six pr9cipal !ories ( prim>y col\rs are giv5 9 ,table ,i1 & illu/rat$ on ,plate ,i1 ) ! names ( ! prim>ies ( ea* !ory opposite ! names ( "s ( _! pr9cipal advocates4 ,x %\ld n be =gott5 :5 comp>+ ^! wide div]g5ces1 t ea* !ory has be5 ! result ( exp]im5tal evid5ce1 9 :at 01 at ! "t1 & rema9s up to ! pres5t1 a new & progressive bran* ( sci5ce4 ,!y agree t ! spectrum col\rs are pur] ?an ! pigm5t>y col\rs1 & t by reason ( _! be+ ref]able to wave l5g? positions1 !y are mo/ adaptable z /&>ds ( col\r4 ,!re has also be5 common agreem5t t c]ta9 col\rs are prim>ies1 & t all o!r col\rs are mixtures ( ^!1 b !re has be5 wide div]g5ce z to _! numb] & ev5 ! col\rs !mselves4 ,illu/ration3 ,,plate ,i ,,illu/rat+ ,,! ,,position ,,( ,,! ,,prim>ies ,,9 ,,relation ,,to ,,! ,,col\rs ,,requir$ ,,to ,,be ,,produc$ ,,by ,,! ,,!oretical ,,mixtures ,,& ,,also ,,9 ,,relation ,,to ,,! ,,*romatic ,,circle4 ,a ,,sev5 ,,ray ,,!ory4 ,,newton4 ,a ,,six ,,ray ,,!ory4 ,,w]n]4 ,a ,,five ,,ray ,,!ory4 ,,newton 7,e>ly74 ,,helmholtz 7,e>ly74 ,a ,,f\r ,,ray ,,!ory4 ,,h]+4 ,a ,,?ree ,,ray ,,!ory4 ,,*evreul4 ,,brew/]4 ,,hay4 ,,r$grave4 ,,field4 ,a ,,?ree ,,ray ,,!ory4 ,,"y-,,helmholtz4 ,to face page #d4 ,lovibond1 ,col\r ,!ories4 ,,*apt] ,,ii4 ,evolution ( ! ,me?od4 ,! writ] 0 =m]ly a brew]1 & ?is "w _h its orig9 9 an obs]vation t ! f9e/ flav\r 9 be] 0 always associat$ ) a col\r te*nically call$ 8gold5 amb]10 & t1 z ! flav\r det]iorat$1 s ! col\r assum$ a r$di% hue4 ,x 0 ^! v>iations 9 t9t t sugge/$ ! idea ( col\r /&>ds z a reliable means ( ref]5ce4 ,! fir/ exp]im5ts 7 made ) col\r$ liquids 9 te/ tubes ( equal diamet]1 & by ^! means "s useful in=mation 0 obta9$2 b z ! liquids soon *ang$ col\r1 frequ5t r5ewals 7 necess>y1 & !re 0 always a difficulty & unc]ta9ty 9 _! exact reproduction4 ,to obviate ?is1 glass 9 diff]5t col\rs 0 tri$1 & long rectangul> w$ges ) regul>ly grad$ tap]s 7 gr\nd & poli%$ = /&>ds1 :il/ correspond+ly tap]$ glass vessels 7 made = ! be]s4 ,^! 7 arrang$ to "w side by side1 & p]p5dicul>ly1 be=e two ap]tures ( an optical in/rum5t1 :i* gave a simultane\s view ( bo?4 ,! ap]tures 7 provid$ ) a fix$ c5tre l9e1 to facilitate ! read+ (f ( comp>isons ( ?ickness4 ,!re 0 no difficulty 9 obta9+ glass :i* approximat$ to ! requir$ col\r :5 us$ 9 "o ?ickness only4 ,b z ?ickness v>i$1 ! te/ no long] held good = bo? /&>ds1 _! rates ( col\r *ange be+ diff]5t1 mak+ ! me?od unreliable4#a #a ,x 0 aft]w>ds f\nd t ^! col\r *anges ?r\gh v>iations ( int5sities 7 due to a natural law to be describ$ "u ! head+ ( 8,specific col\r40 7,see page #cb47 ,! sy/em ab\t to be describ$ is "o ( analytical absorption1 & has be5 publi%$ f "t to "t 9 ! =m ( pap]s1 read be=e ,societies int]e/$ 9 ! "q ( col\r /&>dization2 z also 9 two descriptive works by ! pres5t writ]4 ,! e>li] works 7 necess>ily fragm5t>y1 b ga!r$ sy/em z ! subject progress$4 ,at an e>ly /age 9 ! inve/igations x 0 realiz$ t ! h&books ( ! p]iod dealt l>gely ) !oretical diff]5ces :i* 7 ( little s]vice to ! te*nical work]4 ,"u ^! circum/ances ! writ] appli$ = advice to ! late ,mr4 ,br[n+ ( ! ,/r&1 :o gave x z 8 op9ion t no "w exi/$ :i* c\ld be ( s]vice to ! writ]4 ,all t c\ld be done 0 to g on until some?+ %\ld be arriv$ at4 ,on ?is1 all !oretical read+ 0 put aside1 & ! "w proce$$ on ! simple l9es ( obs]v+1 record+1 & classify+ exp]im5tal facts4 ,9 work+ ) glass ( diff]5t col\rs x 0 f\nd t "s comb9ations develop$ col\r1 :il/ o!r comb9ations de/roy$ x4 ,?is sugge/$ ! probability ( a gov]n+ natural law2 & exp]im5tal "w 0 und]tak5 9 ! hope ( discov]+ x4 ,! result 0 ! con/ruction ( a me*anical scale ( col\r /&>ds1 :i* are n[ 9 use 9 ov] "o ?\s& laboratories1 & no "q ( _! practical accuracy arises4 ,! pr9cipal conditions = ensur+ accuracy & con/ancy ( results are embodi$ 9 ! foll[+ code ( n9e precautions1 :i* h be5 publi%$ = ne>ly tw5ty ye>s )\t be+ disput$4 ,!y may !re=e be consid]$ z gov]n+ laws1 at lea/ = ! pres5t4 ,! col\r !ory adopt$ = ^! ,gov]n+ ,laws has gr[n out ( a s]ies ( exp]im5tal facts capable ( demon/ration1 & is summ$ up 9 ! foll[+ code ( n9e ,laws4 ,laws #a1 #b1 & #c relate to ,:ite & ,col\r$ ,light1 & are z foll[s3-- #a4 ,normal :ite light is made up ( ! six col\r rays1 ,r$1 ,orange1 ,yell[1 ,gre51 ,blue & ,violet 9 equal proportions4 ,:5 ^! rays are 9 unequal proportions ! light is abnormal & col\r$4 #b4 ,! p>ticul> col\r ( an abnormal beam is t ( ! "o prepond]at+ ray1 if ! col\r be simple1 or ( ! two prepond]at+ rays if ! col\r be complex4 ,! dep? ( col\r is 9 proportion to ! prepond]ance4 #c4 ,! rays ( a direct light are 9 a diff]5t condition to ! same rays aft] diffusion1 & give rise to a diff]5t set ( col\r ph5om5a4 ,laws #d1 #e1 #f1 & #g deal ) ,! ,limitations ( ! ,vision to appreciate ,col\r4 #d4 ,! vision is n simultane\sly s5sitive to m ?an two col\rs 9 ! same beam ( light4 ,! col\r ( any o!r abnormal ray is m]g$ 9 ! lum9osity ( ! beam4 #e4 ,! two col\rs to :i* ! vision is simultane\sly s5sitive are always adjac5t 9 _! spectrum ord]1 ,r$ & ,violet be+ consid]$ adjac5t = ?is purpose4 #f4 ,! vision is unable to appreciate col\r 9 an abnormal beam outside c]ta9 limits1 f two causes3 7a7 ,! col\r ( an abnormal beam may be mask$ to ! vision f excess ( lum9osity4 7b7 ,! lum9\s int5sity ( ! abnormal beam may be too l[ to excite def9ite col\r s5sations4 #g4 ,! vision has a v>y+ rate ( appreciation = diff]5t col\rs by "t1 ! l[e/ be+ = r$4 ,! rate increases 9 rapidity ?r\gh ! spectrum1 until ! maximum rate is rea*$ ) violet4 ,& s9ce ?is v>y+ rate necessitates a "t limit = critical obs]vations1 five seconds has be5 adopt$ z ! limit1 no v>iations be+ p]ceptible 9 t "t4 ,laws #h & #i relate to ,col\r ,con/ants4 #h4 ,! col\r ( a giv5 sub/ance ( a giv5 ?ickness is con/ant s long z ! sub/ance itself1 & ! conditions ( obs]vation1 rema9 unalt]$4 #i4 ,e def9ite sub/ance has its own specific rate ( col\r developm5t = regul>ly increas+ ?icknesses4 ,,*apt] ,,iii4 ,evolution ( ! ,unit4 ,! dim5sions ( ! light & col\r unit "h adopt$1 toge!r ) ! scales ( division1 7 9 ! fir/ in/ance physiological1 dep5d+ entirely on ! skill ( normal visions = exactitude4 ,! co-relation ( equal values 9 ! diff]5t col\r scales1 0 secur$ by an elaborate sy/em ( cross-*eck+1 r5d]$ necess>y because ! e/abli%m5t ( a p]fectly col\rless neutral t9t unit1 dem&$ an exact balance 9 values ( ! diff]5t col\r scales4 ,^! scales h /ood ! te/ ( _m ye>s' "w by _m obs]v]s1 & 9 no case has any alt]ation be5 requir$4 ,! orig9al set is /ill 9 use4 ,! fir/ po9t :i* requir$ consid]ation aft] ! want ( /&>d col\r scales 0 realiz$1 0 ! basis & dim5sions ( ! unit4 ,s f> z ! writ] knew !re 0 no publi%$ in=mation be>+ on ?is :i* c\ld be us$ z a guide4 ,sev]al arbitr>y scales = specific purposes _h already be5 con/ruct$ by select+ a col\r dep? :i* c\ld easily be di/+ui%$1 call+ x a unit1 & scal+ x by duplicat+ & subdivid+4 ,?is c\rse 0 adopt$ ) a col\r$ glass :i* approximately mat*$ ,ales & ,malt solutions1 & ano!r :i* mat*$ ,nessl]iz$ ,ammonia solutions4 ,no insup]able difficulty occurr$ 9 con/ruct+ scales available = quantitative "w 9 ^! two in/ances4 ,! int5sity ( ! col\r unit = ^! arbitr>y scales1 0 t :i* appe>$ to be mo/ conv5i5t = ! purpose requir$1 b ! sev]al scales _h no common basis4 ,! unit 0 physiological1 & ! exactitude ( ! scales dep5d$ entirely on ! skill ( ! vision = discrim9at+ small diff]5ces4 ,z ! writ]'s exp]im5tal "w progress$1 x became evid5t t r$1 yell[1 & blue 7 ! only col\rs suitable = sy/ematic "w4 ,! sup]imposition ( any two1 develop$ a ?ird col\r :i* app>5tly _h no relation to ei!r4 ,! sup]imposition ( ! ?ird glass modifi$ or de/roy$ all col\r & r$uc$ ! am\nt ( light4 ,?is sugge/$ ! idea t if ! ?ree col\rs c\ld be s balanc$ t ! light transmitt$ 0 col\rless1 x w\ld be evid5ce ( equival5ce ( int5sity 9 ! individual col\rs4 ,! real difficulty 0 9 obta9+ ?is equival5ce1 because a balance :i* transmitt$ a neutral t9t by "o light develop$ col\r by ano!r4 ,?is necessitat$ ! selection ( a /&>d light4 ,! light f9ally select$ 0 t ( a s-call$ sea fog1 away f ! contam9at+ influ5ce ( t[ns4 ,! :ite fog ( ,salisbury ,pla9 0 us$ z be+ mo/ available4 ,x requir$ two ye>s' "w to e/abli% equival5ce 9 ! unit4 ,illu/ration3 ,,plate ,,ii ,,n9e ,,circles ,,illu/rat+ ,,! ,,analysis ,,( ,a ,,beam ,,( ,,:ite ,,light ,,into ,,! ,,six ,,compos+ ,,col\rs ,,by ,,! ,,absorptive ,,me?od ,a4 ,,:ite ,,light ,b4 ,,divid$ ,,into ,,*romatic ,,equival5ts ,c4 ,,:olly ,,absorb$ ,,col\rs ,,( ,,! ,,fir/ ,,division ,,develop$ ,,by ,,! ,,absorption ,,( ,,! ,,?ree ,,complim5t>ies #a #b #c ,,col\rs ,,( ,,! ,,second ,,division ,,develop$ ,,by ,,! ,,absorption ,,( ,,! ,,five ,,o!r ,,rays #d #e #f ,to face page #aa4 ,lovibond1 ,col\r ,!ories4 ,,*apt] ,,iv4 ,d]ivation ( ,col\r f ,:ite ,light4 ,! me?od ( analys+ :ite light into its col\r con/itu5ts by means ( col\r$ glass absorb5ts ( kn[n int5sity & purity1 is illu/rat$ by ! set ( n9e circles 9 ,plate ,,ii1 :i* demon/rate t col\r is develop$ by ! absorption ( ! complem5t>y col\r rays4 ,! ratios ( transmission are equal4 ,9 ?is set ( illu/rations ! circles repres5t light ( #bj units lum9\s int5sity1 & ! absorptive value ( ! ?ree glass col\rs is ea* ( #bj units1 !re=e ! :ole ( ! light & col\r en]gies are presum$ to be dealt )4 ,9 ! fir/ set ( ?ree circles1 ,a repres5ts a beam ( normal :ite light4 ,b a simil> beam z divid$ into ! six col\r rays1 ,r$1 ,orange1 ,yell[1 ,gre51 ,blue & ,violet 9 equal proportions1 ,c z :olly absorb$ by ,r$1 ,yell[1 & ,blue glasses1 ea* ( #bj units col\r int5sity4 ,figures #a1 #b & #c repres5t ! specific action ( ,r$1 ,yell[1 & ,blue glass on ! :ite light4 ,r$ absorbs ,yell[1 ,gre5 & ,blue1 transmitt+ ,violet1 ,r$ & ,orange1 develop+ ,r$ only4 ,yell[ absorbs ,blue1 ,violet1 & ,r$1 transmitt+ ,orange1 ,yell[ & ,gre51 develop+ ,yell[ only4 ,blue absorbs ,r$1 ,orange & ,yell[1 transmitt+ ,gre51 ,blue1 & ,violet1 develop+ ,blue only4 ,by ?is me?od ( developm5t1 ,r$1 ,yell[ or ,blue1 :5 se5 alone are visually mono*romatic1 al?\gh composite 9 /ructure1 ea* conta9+ a gr\p ( ?ree rays1 ! middle ray alone excit+ ! col\r s5sation4 ,circles #d1 #e1 & #f illu/rate ! developm5t ( ,orange1 ,gre5 & ,violet f ! triad gr\ps1 by int]cept+ ! light ) two glass col\rs4 ,circle #d1 ,r$ on ,yell[1 develops ,orange by absorb+ ,yell[1 ,gre51 ,blue1 ,violet & ,r$4 ,circle #e1 ,yell[ on ,blue1 develops ,gre5 by absorb+ ,blue1 ,violet1 ,r$1 ,orange & ,yell[4 ,circle #f1 ,blue on ,r$1 develops ,violet by absorb+ ,r$1 ,orange1 ,yell[1 ,gre5 & ,blue4 ,by ?is me?od ( demon/ration ! six col\rs fall naturally into two gr\ps4 ,! fir/ gr\p includes ,r$1 ,yell[1 & ,blue1 :il/ ! second gr\p includes ,orange1 ,gre51 & ,violet4 ,! col\rs ( ! second gr\p1 ,orange1 ,gre51 & ,violet1 are true mono*romes1 ea* be+ isolat$ f ! light1 by ! absorption ( ! five o!r rays4 ,^! illu/rations deal ) light & col\r ( #bj units int5sity2#b z ! int5sity ( ! light "h is exactly equal to ! absorptive p[] ( ! /&>ds1 no free light rema9s2 :]e ! absorptive p[] ( ! col\r /&>ds is less ?an ! light1 associat$ :ite light rema9s2 = in/ance1 if only "o unit ( col\r 0 develop$1 #ai units associat$ :ite light w\ld rema94 #b ,= description ( ! light & col\r units1 ref] to *ap4 ,,iii1 page #i4 ,illu/ration3 ,,plate ,,iii ,to face page #ac4 ,lovibond1 ,col\r ,!ories4 ,?is me?od ( col\r developm5t by analytical absorption is fur!r illu/rat$ by ,plate ,,iii1 %[+ ! effect ( sup]imposition ( ! ?ree col\rs 9 _! sev]al comb9ations z int]cept+ a beam ( :ite light4 ,n all lights :i* appe> :ite to ! vision are truly normal :ite2 col\r may be mask$ by excess ( lum9osity1 & only become evid5t :5 ! lum9osity has be5 r$uc$1 by plac+ neutral t9t /&>ds betwe5 ! light & ! obs]v]4 ,direct sunlight1 & "s artificial lights1 are in/ances4 7,law #f 7a7 page #h47 ,on ! o!r h&1 an abnormal light may be too l[ = ! vision to discrim9ate col\r4 ,?is may be obs]v$ 9 nature by ! gradual loss ( col\r 9 fl[]s1 etc41 9 ! wan+ int5sities ( ev5+ light4 ,! ord] ( _! disappe>ance is %[n 9 ,*>t ,i4 ,,*apt] ,v4 ,/&>d ,:ite ,light4 ,! col\r ( a sub/ance is det]m9$ by ! ray composition ( ! light x reflects1 or transmits to ! vision1 ! col\r w\ld !re=e v>y ) e *ange 9 ! ray proportions ( ! incid5t light2 x foll[s t con/ancy 9 col\r measurem5t c only be obta9$ by a col\rless light4 ,up to ! pres5t diffus$ daylight is ! only light :i* complies ) ! condition ( ray equality4 ,! absolute equality ( ! six spectrum col\rs may be difficult to e/abli% 9 any light1 & _! con/ancy 9 equival5ce "u v>y+ light int5sities may be op5 to argum5t4 ,b1 z ev]yday "w is c>ri$ on ma9ly "u daylight conditions1 & z ! vision is ! f9al arbit] = col\r "w1 !oretical que/ions outside ! discrim9at+ p[] ( ! vision1 ne$ be no b> to ! e/abli%m5t ( a work+ /&>d :ite light2 & 9 say+ t diffus$ daylight is normal :ite1 x is only int5d$ to mean3 ,9 s f> z a normal vision c det]m9e4 ,ap>t f any !oretical explanation x is an exp]im5tal fact1 t ! abnormal rays ( direct sunlight1 & "s artificial lights1 may be s modifi$ by diffusion z to be available = a limit$ range ( col\r "w4 ,9 ! case ( diffus$ nor? sunlight1 :5 tak5 f opposite ! sun's m]idian1 ! modification is suffici5t to make x available z a /&>d :ite light4 ,9 ! case ( artificial lights1 _! use is1 z yet1 limit$ to visual mat*+ 7n record+7 & arbitr>y comp>isons4 ,,! ,,black ,,unit4 ,ideal black is total abs5ce ( light1 & c only be realiz$ z a s5sation1 9 ! pres5ce ( light1 :i* may h[ev] be 9 contra/ or 9 association4 ,! ne>e/ approa* to ideal black by contra/1 is to view a hole 9 a box ) a black5$ int]ior1 s arrang$ t no light ent]+ ! hole1 c be reflect$ back to ! vision3 9 ?is way associat$ light1 if n entirely abs5t1 is r$uc$ to a m9imum & total d>kness is practically realiz$ by ! vision 9 contra/ ) ! surr\nd+ light4 ,pigm5t>y black view$ "u diffus$ daylight conditions is always associat$ ) :ite light1 z no sub/ance1 h[ev] black x may be1 absorbs all ! imp++ light2 z examples1 ! foll[+ measurem5ts ( ?ree :ite & ?ree black pigm5ts 7 made at an angle ( #de degrees ) a light int5sity ( #be units4 ,?is is a true quantitative analysis ( ! #be units ( :ite light aft] reflection f ! black pigm5ts4 ,! black units repres5t ! proportion ( :ite light absorb$1 :il/ ! beams reflect$ f ! pigm5ts consi/ ( ! col\r values develop$ :i* are associat$ ) ! unabsorb$ :ite light4 ,,table ,,ii4 ---------------------------------------- --------------------- ,lime ,blue ,lamp ,ivory ,z9c ,:ite ,sulphate,black ,black ,black ,:ite ,lead ---------------------------------------- --------------------- ,/&>d light units #bej ---------------------- ,black units 7light absorb$7 #ij #ib #ib -- #jh ,violet units 7col\r develop$7 #bb #ad #ad -- -- ,blue units 7col\r develop$7 #aj #ai #d #ja #je ,gre5 units 7col\r develop$7 -- -- -- -- #jg ,associat$ :ite light #abh #abe #adj #bdii #bdhj ---------------------------------------- --------------------- ,totals #bej #bej #bej #bej #bej #bej ---------------------------------------- --------------------- ,! analyses demon/rate t black is n itself an active en]gy analog\s to col\r1 b is a m9us quantity di/+ui%able by contra/ ) ! orig9al light4 ,! reflect$ beam consi/s ( ! col\r develop$1 associat$ ) ! residue ( unalt]$ light4 ,note4--,suitable proportions ( ,violet & ,blue give "* & value to black1 :il/ ,orange & ,yell[ are less pleas+ z t5d+ to ru/9ess4 ,,*apt] ,,vi4 ,qualitative ,col\r ,nom5clature4 ,,simple ,,col\rs4 ,! vision c sep>ate six mono*romatic col\rs f a beam ( :ite light1 !re=e 9 practical "w six mu/ be dealt )1 no matt] h[ !y may be !oretically acc\nt$ =4 ,!y naturally take ! accept$ spectrum names & symbols already 9 use4 ,to ^! are add$ two o!r t]ms1 ,bk4 to signify black1 & ,l4 = light2 ^! t]ms deal ) ! brightness1 or d+9ess1 ( a col\r4 ,simple ,t]ms4 ,symbols4 ,r$ ,r ,orange ,o ,yell[ ,y ,gre5 ,g ,blue ,b ,violet ,v ,black ,bk ,:ite ,l ,,complex ,,col\rs4 ,! ord] ( ! association ( simple col\rs to =m complex1 is gov]n$ by two factors4 ,! fir/ is a physiological limitation ( ! vision1 :i* is unable to simultane\sly di/+ui% m ?an two col\rs1 9 ! same beam ( light1 ?is limits ! mo/ complex col\r to two col\r names4 ,! second limitation is "o ( association1 bas$ on ! exp]im5tal fact1 t ! p>ticul> two mu/ be adjac5t 9 _! spectrum ord]1 spectrum r$ & violet be+ consid]$ adjac5t = ?is purpose4 ,"u ^! conditions1 any giv5 col\r mu/ be ei!r a mono*rome1 or a bi*rome1 & all complex col\rs mu/ be bi*romes4 ,!re=e ! only possible comb9ations are z foll[s3-- ,r$ & ,orange ,orange ,yell[ ,yell[ ,blue ,blue ,gre5 ,gre5 ,violet ,violet ,r$ ,! classifi$ ord] ( associat+ symbols = describ+ ! compon5ts ( ! :ole range ( di/+ui%able col\rs is set out 9 ! foll[+ tables3-- -------------------------------------- ,mono*romes ,mono*romes ,mono*romes ( a ,/&>d,bright] ?an,dull] ?an ,brightness4 ,/&>ds4 ,/&>ds4 -------------------------------------- ,r4 ,r4 ,l4 ,r4 ,bk4 ,o4 ,o4 ,l4 ,o4 ,bk4 ,y4 ,y4 ,l4 ,y4 ,bk4 ,g4 ,g4 ,l4 ,g4 ,bk4 ,b4 ,b4 ,l4 ,b4 ,bk4 ,v4 ,v4 ,l4 ,v4 ,bk4 -------------------------------------- ,illu/ration ,! sep>ation ( ! six mono*romatic s5sations f a po9t ( :ite light1 & ! =mation ( b9>y s5sations by ! comb9ation ( adjac5t col\rs1 is graphically illu/rat$ 9 ! above diagram4 ,9 ord] to make ! qualitative symbols quantitative x is only necess>y to add ! num]ical unit value to ea* factor z f\nd by direct exp]im5t4 ,,*apt] ,,vii4 ,quantitative ,col\r ,nom5clature4 ,,! ,,glass ,,/&>d ,,scales4 ,at an e>ly /age ( ! inve/igation1 x 0 f\nd t col\r$ glass gave bett] results ?an col\r$ solutions1 & t ,r$1 ,yell[1 & ,blue1 7 ! only col\rs suitable = sy/ematic "w2 x 0 also f\nd t any col\r c\ld be produc$ by _! comb9ation4 ,z already describ$ arbitr>y scales 7 fir/ us$ 9 _m col\rs1 b 7 sup]s$$ by ^! ?ree1 :i*1 :5 grad$ into scales ( equival5t value1 7 f\nd to cov] all daylight col\rs4 ,^u ?is evid5ce1 scales ( r$1 yell[ & blue 7 con/ruct$ ( glass slips1 ea* scale be+ all ( "o col\r1 ) a regul> v>iation ( int5sity f #jja to #bjj units1 equal units ( ! ?ree scales be+ 9 equival5ce ) ea* o!r4 ,! dim5sions ( ! unit are necess>ily arbitr>y1 b ! scales comply ) ! ess5tials ( a sci5tific /&>d1 9 t ! divisions are equal1 & ! unit recov]able4 ,! equality ( ! unit divisions 9 ! scales1 is demon/rat$ by a sy/em ( cross-*eck+4 ,! te/ ( col\r equival5ce has already be5 describ$ on pages #aj & #bh4 ,! p[] ( recov]+ ! unit1 is by co-relation to well-kn[n physical col\r con/ants1 su* z is easily obta9$ by def9ite int5sities ( p]c5tage solutions1 ( select$ pure *emical comp\nds 9 di/ill$ wat]1 at /&>d temp]atures4 ,= example1 a "o p] c5t4 solution ( pure cry/alliz$ copp] sulphate ,c#b,,s#de;,h#b,o at #fj ,f4 :5 view$ 9 ! optical in/rum5t 9 a #a-;in* /ratum1 mu/ be mat*$ by a comb9ation ( ,yell[ #aeh & ,blue #aee4 ,! in* ( di/ill$ wat] itself con/itutes v little ( ?is col\r2 ! col\r ( di/ill$ wat] is rem>kably uni=m1 & might almo/ be tak5 z a col\r con/ant1 ?us3 ,a #b-;foot /ratum is mat*$ by ,yell[ #ja & ,blue #jcd1 a #d-;foot /ratum by ,yell[ #aj & ,blue #ade4 ,a "o p] c5t4 solution ( ,nickel ,sulphate ,ni,s,o#dg;,h#b,o1 tem4 #fj ,f4 9 a #b-;in* /ratum mu/ be mat*$ by #bb ,blue & #bj ,yell[ units4 ,a "o p] c5t4 solution ( ,potassium ,bi*romate ,k#b;,cr#b,o1 ,tem4 #fj & 9 a #b-;in* /ratum aft] be+ dull$ by #je neutral t9t units mu/ be mat*$ by #cdj yell[ & #if r$ units4 ,,me?od ,,( ,,develop+1 ,,measur+ ,,& ,,nam+ ,,col\r4 ,! s+le s5sation col\rs1 ,r$1 ,yell[ & ,blue1 are mat*able by a s+le glass f ! correspond+ col\r scale2 ! dep? ( col\r is directly indicat$ by ! value ( ! glass us$4 ,! s+le s5sation col\rs1 ,orange1 ,gre5 & ,violet1 are mat*able by a comb9ation ( equal units1 f two ( ! /&>d scales1 ! dep? ( col\r is directly indicat$ by ! unit value ( ei!r ( ! glasses1 ?us3 #bj ,blue #bj ,r$ develop #bj units ,violet4 ,a giv5 neutral grey is mat*able by a comb9ation ( equal units f ! ?ree /&>d scales1 ! dep? ( grey1 is directly indicat$ by ! unit value on ei!r ( ! glasses us$1 ?us3-- #cj ,r$ #cj yell[ #cj blue develop #cj units neutral t9t4 ,! complex col\r s5sations1 r$ & yell[ oranges1 yell[ & blue gre5s1 blue & r$ violets are mat*able by unequal glasses f two ( ! /&>d scales2 ! col\r develop$ is n directly indicat$ by ! unit value ( ! glasses1 b is record$ by means ( an equation1 ! fir/ half ( :i* conta9s ! sep>ate values ( ! glasses us$1 & ! second half ! names & ! dep? ( ! col\rs !y transmit4 ,= in/ance-- ,! equation ( a col\r mat*$ by #agj r$ & #bf blue units1 is z foll[s3-- ,/&>d ,glasses4 ,col\r ,develop$4 ,r$4 ,blue4 ,violet4 ,r$4 #agj #bf #bf #add ,! col\r develop$ is a r$ violet 9 ^! proportions4 ,a col\r mat*$ by ,/&>d ,glasses4 ,col\r ,develop$4 ,r$4 ,yell[4 ,orange4 ,r$4 #ajj #cj #cj #gj ,! col\r develop$ is a r$ orange 9 ^! proportions4 ,a col\r mat*$ by ,/&>d ,glasses4 ,col\r ,develop$4 ,yell[4 ,blue4 ,gre54 ,yell[4 #cj #ae #ae #ae ,! col\r develop$ is a yell[ gre5 9 ^! proportions4 ,a col\r mat*$ by ,/&>d ,glasses4 ,col\r ,develop$4 ,blue4 ,r$4 ,blue4 ,violet4 #fj #ah #db #ah ,! col\r develop$ is a blue violet 9 ^! proportions4 ,! /&>d glass col\rs are necess>ily ( a giv5 brightness1 & col\rs = measurem5t may be ei!r bright]1 or sadd] ?an ! /&>ds4 ,a giv5 complex col\r ( less ?an glass /&>d brightness1 is mat*able by unequal numb]s f ! ?ree /&>d scales2 ! smalle/ unit value always repres5ts ! 8black10 or neutral unit factor4 ,! equation is z foll[s3-- ,a col\r mat*$ by ,/&>d ,glasses4 ,col\r ,develop$4 ,r$4 ,yell[4 ,blue4 ,neutral ,t9t4 ,gre54 ,blue4 #aj #cj #ij #aj #bj #fj ,! col\r is a blue gre51 9 ! proportion ( six to two1 sadd5$ by "o ( neutral t9t4 ,a giv5 complex col\r ( great] brightness ?an ! glass /&>ds1 is fir/ dull$ by ! int]ception ( neutral t9t units1 until measurable 9 ! mann] describ$ above2 ! int]cept+ glasses repres5t ! unit value ( excess ( brightness1 & is %[n 9 ! equation z light units1 = in/ance-- ,/&>d ,glasses4 ,col\r ,develop$4 ,neutral ,t9t4 ,yell[4 ,blue4 ,light4 ,gre54 ,yell[4 #ae #ge #je #ae #je #gj ,! col\r is a yell[ gre5 9 ! proportions ( #gj ( yell[1 to #je ( gre51 & #ae bright] ?an ! /&>ds4 ,e daylight col\r be+ ?us measurable by a suitable comb9ation ( /&>d glasses1 ) or )\t ! addition ( a ,light1 or a ,neutral ,t9t factor1 x foll[s t any col\r c be describ$ bo? qualitatively1 & quantitatively1 9 t]ms ( ! col\r s5sations yield$ by ! /&>d glasses & _! comb9ation4 ,! di/9ct col\r s5sations are ^?1 :i*1 by common cons5t are kn[n z ,r$1 ,yell[1 ,blue1 ,orange1 ,gre5 & ,violet1 & !y are yield$ by s+le glasses1 or by pairs z already describ$2 all col\rs !re=e fall into ! foll[+ categories3-- ,a4--,s+le col\r s5sations3-- #a4 ,transmitt$ by s+le glass /&>ds3 ,r$4 ,yell[4 ,blue4 #b4 ,transmitt$ by equival5t pairs ( /&>d glasses3 ,orange4 ,gre54 ,violet4 ,b4--,d\ble col\r s5sations transmitt$ by unequal pairs ( /&>d glasses4 ,r$ orange1 transmitt$ by unequal units ( r$ & yell[1 r$ prepond]at+4 ,yell[ orange1 transmitt$ by unequal units ( r$ & yell[1 yell[ prepond]at+4 ,yell[ gre51 transmitt$ by unequal units ( yell[ & blue1 yell[ prepond]at+4 ,blue gre51 transmitt$ by unequal units ( yell[ & blue1 blue prepond]at+4 ,blue violet1 transmitt$ by unequal units ( blue & r$1 blue prepond]at+4 ,r$ violet1 transmitt$ by unequal units ( blue & r$1 r$ prepond]at+4 ,c4--,any ( ! above col\rs ) ! addition or subtraction ( neutral t9t4 ,neutral t9t itself1 is transmitt$ by a comb9ation ( equal units ( ! /&>d glasses1 ?us ?ree units r$1 yell[ & blue1 :5 sup]pos$1 transmit ?ree units neutral t9t4 ,,examples4 ,?ree units r$1 ( /&>d brightness1 completely describes a col\r mat*$ by a r$ glass ( ?ree units1 & is d5ot$ ,r4 #cj ,?ree units r$ sadd5$ by "o neutral t9t1 completely describes a col\r mat*$ by a r$ glass /&>d ( f\r units r$1 comb9$ ) a blue & yell[ ( "o unit ea*1 & is d5ot$ ,r4 #cj ,n4,t4 #aj ,a giv5 r$ ( ?ree units1 :i* is "o unit bright] ?an /&>ds1 aft] hav+ be5 sadd5$ by "o unit ea* ( r$1 yell[ & blue1 is mat*$ by ?ree units ( r$ & is correctly describ$ by ,r$ #cj ,light #aj ,?ree units ( violet1 ( /&>d brightness1 is mat*$ by a r$ & a blue glass ( ?ree units1 & is correctly describ$ by ,v4 #cj ,?ree units ( orange1 ( /&>d brightness1 is mat*$ by a r$ & a yell[ glass ( ?ree units1 & is correctly describ$ by ,o4 #cj ,a b9>y r$ violet ( /&>d brightness1 9 :i* r$ prepond]ates by "o unit1 is mat*$ by f\r units r$1 & a blue ( ?ree units1 & is correctly describ$ by ,r4 #aj ,v4 #cj ,a b9>y r$ orange1 ( /&>d brightness1 9 :i* orange prepond]ates by ?ree units1 is mat*$ by r$ f\r & yell[ ?ree units1 & is correctly describ$ by ,r4 #aj ,o4 #cj ,a r$ orange1 ( less ?an /&>d brightness by "o unit1 9 :i* orange prepond]ates by ?ree units1 is mat*$ by a r$ five1 yell[ f\r1 blue "o1 & is correctly describ$ by ,r4 #ai ,o4 #cj ,n4,t4 #aj ,a r$ violet1 9 :i* r$ prepond]ates by "o unit1 & is "o unit bright] ?an /&>d1 is fir/ dull$ by "o unit r$1 yell[ & blue1 & !n mat*$ by f\r r$ & ?ree blue1 & is correctly describ$ by ,r4 #aj ,v4 #cj ,light #aj ,a r$ orange1 9 :i* r$ prepond]ates by "o unit1 & is "o unit bright] ?an /&>d1 is fir/ dull$ by "o r$1 yell[ & blue1 & !n mat*$ by f\r r$1 & ?ree yell[1 & is correctly describ$ by ,r4 #aj ,o4 #cj ,light #aj ,,*apt] ,,viii4 ,! ,col\r ,scales4 ,a normal vision "u ord9>y conditions1 has no hesitation 9 correctly nam+ ! s5sations produc$ by ! triad gr\ps r$1 yell[ & blue1 or by ! s+le rays orange1 gre5 & violet4 ,x c also correctly describe a complex col\r s5sation1 by nam+ ! two associat$ col\rs1 su* z r$ orange1 yell[ orange1 blue gre51 blue violet1 etc42 b :5 call$ ^u to decide diff]5ces ( col\r dep?1 x c only d s by us+ arbitr>y t]ms ( no precise sci5tific value1 su* z light1 m$ium1 d>k1 etc4 ,?is defici5cy is because ! vision has 9 itself no arrangem5t = ! quantitative def9ition ( col\r dep?4 ,?is want c only be met by co-relat+ col\r s5sations1 to "s physical col\r con/ants4 ,?is co-relation has n[ be5 effect$ by a s]ies ( glass /&>d col\r scales1 :i* are num]ically grad$ = col\r dep?1 ! scales !mselves be+ col\r con/ants by co-relation to p]c5tage solutions1 ( su* col\r$ *emicals1 z copp] sulphate1 nickel sulphate1 potassium p]manganate1 etc4 ,^! sub/ances z well z _m o!rs1 are always available = *eck+ ! con/ancy ( ! scales1 or = recov]+ ! unit if lo/4 ,z already m5tion$1 ! sy/em ( tap] scales prov$ to be useless = ! purpose1 n only because ! rate ( col\r increase 0 nev] 9 proportion to ! rate ( ?ickness increase1 b also because no two sub/ances are equal 9 ?is respect1 ea* hav+ a rate specific to itself4 ,! prismatic spectrum col\rs 7 n available = sev]al reasons1 fir/ z be+ unsuitable = critical comp>isons "u daylight conditions1 z be+ too weak except 89 cam]a02 also !y 7 f\nd to be too cr[d$ = ! sep>ation ( a work+ area ( mono*romatic col\r1 & "s corrections w\ld h be5 necess>y = v>iation 9 ! refractions ( diff]5t col\r rays4 ,?is is m fully dealt ) "u ! head+ ( ,! ,spectrum 9 relation to ,col\r ,/&>dization1 page #cf4 ,,! ,,equival5ce ,,( ,,! ,,col\r ,,scales4 ,! me?od employ$ = obta9+ equality ( ! unit divisions1 & col\r equival5ce betwe5 ! diff]5t scales 0 z foll[s3-- ,two slips ( r$ glass 9 a light %ade 7 made exactly equal 9 col\r1 & consid]$ z initial units2 ^! 7 !n sup]impos$ & mat*$ by a s+le glass1 :i* 0 !n consid]$ z ( two units1 ?is & "o ( ! initial units 7 sup]impos$1 & mat*$ by a s+le glass ( ?ree col\r units1 & s on1 until a progressive r$ scale 0 con/ruct$1 rang+ 9 int5sity f #ja to #bj units4#c #c ,x 0 f\nd t ! sup]imposition ( two glasses did n visually di/urb equival5ce1 !re=e only two glasses 7 us$ = ea* obs]vation 9 con/ruct+ ! scales4 ,! yell[ & blue scales1 7 simil>ly con/ruct$1 tak+ c>e t _! simil> unit values 7 9 col\r equival5ce ) ! r$ units1 ! te/ ( equival5ce be+1 t :5 equal units ( ! ?ree scales 7 sup]impos$ aga9/ a normal :ite light1 a neutral grey 0 transmitt$1 9 :i* no trace ( col\r c\ld be p]ceiv$ by ! common cons5t ( ! :ole /aff ( tra9$ obs]v]s4 ,! scales 7 !n consid]$ z 9 col\r equival5ce ) ea* o!r4 ,! sy/em ( cross-*eck+ 0 s elaborate1 t aft] ! equival5ce ( ! fir/ unit 0 e/abli%$1 ne>ly f\r ye>s 0 occupi$ 9 ! "w be=e ! scales 7 pass$ z satisfactory4 ,x may be urg$ t ! unit is arbitr>y1 b ?is applies also to ! unit ( any o!r /&>d scale2 x is suffici5t t ! ess5tials ( a philosophic scale are compli$ )1 9 t ! divisions are equal1 & ! unit recov]able4 ,illu/ration3 ,,plate ,,iv ,,comp>ison ,,curves ,,( ,,heal?y ,,human ,,blood ,,) ,,! ,,blood ,,( ,,l[] ,,animals4 ,to face page #ca4 ,lovibond1 ,col\r ,!ories4 ,,*apt] ,,ix4 ,col\r ,*>ts4 ,a col\r *>t is con/ruct$ by plac+ two col\r scales at "r angles to ea* o!r1 ) _! z]os at ! angle4 ,a measur$ simple col\r1 f9ds its position directly on its correspond+ col\r scale at ! po9t ( its measur$ value4 ,a measur$ complex col\r1 f9ds its position )9 ! angle1 at t po9t :]e p]p5dicul>s drawn ?r\gh ! two col\r values meet4 ,! above /atem5ts are complete only = col\rs ( /&>d brightness1 %\ld ! col\r be bright] or dull] ?an /&>ds1 a light factor is necess>y1 ! value ( :i* is furni%$ by ! measurem5t itself1 & mu/ be writt5 9 num]als ne> ! col\r po9t4 ,by ?is me?od ! *>t position ( ev5 ! mo/ complicat$ col\r is indicat$ by a s+le po9t :i* is det]m9$ by ! analytical value ( ! compos+ factors4 ,,examples4 ,simple ,col\r ( ,complex ,col\r ,/&>d ( ,/&>d ,brightness4 ,brightness4 #c ,r$4 #f ,blue1 #aj ,violet4 ,simple ,col\r ,complex ,col\r ,bright] ?an ,dull] ?an ,/&>ds4 ,/&>ds4 #g ,yell[1 ,r$ #f1 ,orange #e1 ,light #b ,black #b4 ,! numb] ( complex col\r *>ts is limit$ to ! six repres5t$ 9 ,fig4 #a z ly+ 9 _! ord] on a cont9u\s spectrum4 ,! r$ & violet mixtures hav+ no visible spectrum position are repres5t$ 9 ! ultra violet4 ,! ord9ates ( ! *>ts are made by erect+ ! ov]ly+ r$1 yell[ & blue scales z p]p5dicul>s4 ,illu/ration3 ,fig4 #a4 ,! in=mation to be obta9$ by *>t+ measur$ col\r is m ext5sive ?an appe>s at fir/ sight1 z by v>y+ ! "* ( ! co-ord9ates1 & *>t+ suitable s]ies ( measurem5ts1 new fields ( inve/igation are op5$1 ?us ?r[+ light on "s hi!rto obscure que/ions1 ( :i* ! foll[+ are "s in/ances4 ,,specific ,,col\r4 ,x has sometimes be5 assum$ t col\r increase 0 9 direct ratio to int5sity increase1 b ?is is nev] ! case1 ea* sub/ance has its own rate1 specific to itself4 ,x is conceivable t ! col\rs ( two sub/ances may co9cide at "o po9t1 b z _! d5sities increase1 or decrease1 _! rates ( *ange v>y4 ,! t]m 8,specific ,col\r0 is bas$ on ! exp]im5tal fact1 t ! col\r ( a giv5 sub/ance is con/ant1 s long z ! sub/ance itself & ! conditions ( obs]vation1 rema9 unalt]$4 ,dur+ exp]im5tal "w a suffici5t numb] ( in/ances h accumulat$ to w>rant ! writ] 9 advanc+ & us+ ! t]m 8,specific ,col\r0 z describ+ a new natural law1 z rigid 9 its application z t ( 8,specific ,gravity0 or 8,specific ,heat40 ,illu/ration3 ,,plate ,v ,,absorption ,,curves ,,( ,,five ,,col\r ,,con/ants4 ,to face page #cc4 ,lovibond1 ,col\r ,!ories4 ,:5 ?is pr9ciple is appli$ to ! measurem5t ( regul>ly increas+ ?icknesses1 curves ( col\r *anges c be e/abli%$1 :i* are specific = ! sub/ance 9 "q1 & af=d a c]ta9 means ( id5tify+ simil> sub/ances 9 future4 ,?is is effect$ by v>y+ ! nature ( ! co-ord9ates1 mak+ ! ord9ates to repres5t ! t9tometrical scale ( col\r units irrespective ( col\r1 :il/ ! abscissae repres5t ! scale ( increas+ ?icknesses4 ,!n by plott+ ! sep>ate factors ( ea* measurem5t accord+ to _! unit values1 a s]ies ( curves is e/abli%$1 specific to ! sub/ance 9 "q1 & applicable to none o!r4 ,we h n[ two sy/ems ( *>t+ col\r1 9 ! fir/1 ! complete s5sation is repres5t$ by a s+le po9t1 z 9 ,plate ,,iv4 ,9 ! second1 ea* factor is repres5t$ by a sep>ate po9t1 & by connect+ po9ts ( simil> col\rs1 a s]ies ( curves is e/abli%$ :i* repres5ts a quantitative analysis ( ! progressive col\r developm5t1 z 9 ,plate ,v4 ,,*apt] ,x4 ,repres5tations ( ,col\r 9 ,space ( ,?ree ,dim5sions4 ,! relations ( ! diff]5t col\rs to "o ano!r1 & to neutral t9t are1 p]haps1 be/ repres5t$ to ! m9d by a solid model1 or by ref]5ce to ?ree co-ord9ate axes1 z employ$ 9 solid geometry 7see ,fig4 #b74 ,illu/ration3 ,fig4 #b4 ,let ! ?ree adjac5t edges ,,or1 ,,ob1 ,,oy1 ( ! above cube be ?ree axes1 along :i* are measur$ degrees ( ,r$1 ,yell[ & ,blue respectively1 />t+ f ! orig9 ,o4 ,e po9t 9 space on ! positive side ( ?is orig9 w !n repres5t a conceivable col\r1 ! con/itu5ts ( :i* 9 degrees ( r$1 yell[ & blue are measur$ by ! ?ree co-ord9ates ( ! po9ts4 ,pure r$s lie all along ! axis ,,or1 pure yell[s on ! axis ,,oy1 & pure blues on ! axis ,,ob4 ,all normal oranges1 normal gre5s1 & normal violets lie on ! diagonals ( ! faces ( ! cubes ,,oo#a1 ,,og1 ,,ov respectively4 ,pure neutral t9ts lie on ! diagonal ,,on ( ! cube1 equally incl9$ to ! ?ree pr9cipal axes4 ,r$ violets w be f\nd on ! plane ,,rob1 betwe5 ,,ov & ,,or4 ,blue violets on ! same plane betwe5 ,,ov & ,,ob4 8,sadd5$0 r$ violets all )9 ! w$ge or op5 space enclos$ by ! ?ree planes1 ^: b\nd>ies are ,,ob1 ,,ov1 ,,on4 ,! o!r col\rs1 r$ & yell[ oranges1 blue & yell[ gre5s1 pure & sadd5$1 are f\nd 9 correspond+ positions 9 relation to ! o!r cases4#d #d ,?is me?od ( illu/ration 0 sugge/$ by ,dr4 ,h]b]t ,munro4 ,,*apt] ,,xi4 ,! ,spectrum 9 relation to ,col\r ,/&>dization4 ,! spectrum has naturally be5 consid]$ z a suitable s\rce = col\r /&>ds1 b ! p[] ( analys+ has disclos$ "s difficulties1 :i* h yet to be ov]come4 ,conc]n+ ! prismatic spectrum1 !re has always be5 a difficulty 9 apportion+ ! diff]5t col\rs to specific areas1 & fur!r1 be=e ?is spectrum is available = col\r /&>dization1 "s me?od ( correction = ! unequal di/ribution ( col\rs mu/ be devis$4 ,nei!r ( ^! difficulties occur 9 ! use ( ! diffraction spectrum1 :]e ! pure col\rs are apportion$ by ,pr(essor ,rood f ,a to ,h 9 ! mann] %[n 9 table on next page4 ,pr(essor ,rood fur!r divides ! spectrum f ,a to ,h into #ajj equal divisions1 allott+ #bj unit divisions ( #gb1gaf wave l5g?s to ! space betwe5 ea* two col\r l9es4 ,?is allots a space ( #c1fce ,w4,l4 to ea* unit division1 z %[n 9 ,table ,,iii4 ,,table ,,iii4 ---------------------------------------- --------------------- ,no4 ( ,wave ,l5g?s ,w4,l4,k4 ,wave ,l5g? ,position4 f ,division p] ,col\r ,division betwe5 ea*4 ---------------------------------------- --------------------- #gfj1djj ,a4 ,r$ #gfj1djj ----------------------- #gb1gag #bj #c1fce ,orange #fhg1fhc ----------------------- #gb1gaf #bj #c1fce ,yell[ #fad1ifg ----------------------- #gb1gaf #bj #c1fce ,gre5 #edb1bea ----------------------- #gb1gaf #bj #c1fce ,blue #dfi1ece ----------------------- #gb1gaf #bj #c1fce #cif1hai ,h4 ,violet #cif1hai ---------------------------------------- --------------------- #cfc1eha ,total ,w4,l4 betwe5 ,a4 ,h4 #cfc1eha #ajj ---------------------------------------- ---------------------- ,hav+ provid$ equal wave l5g? positions = ! six pure col\rs1 ! int]m$iate col\rs are necess>ily b9>ies 9 def9ite proportions1 acc\nt$ = by a regul> ov]lapp+ ( two b\nd+ col\rs 9 opposite directions f z]o to #bj1 z %[n 9 ! foll[+ table f ,r$ to ,orange1 repres5t+ ! space betwe5 ^! two pure col\rs4 ,r$ #bj #ai #ah #ag #af #ae #ad #ac #ab #aa #aj #i #h #g #f #e #d #c #b #a #j ,w4,l ,w4,l #fhg1 #gfj1 #j #a #b #c #d #e #f #g #h #i #aj #aa #ab #ac #ad #ae #af #ag #ah #ai #bj #fhc #djj ---------------------------------------- ---------------------- ,orange4 #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj #bj ,x foll[s1 t ap>t f ! six mono*romes1 all spectrum complex col\rs 9 a s+le wave l5g? mu/ be b9>ies1 ^: unit$ values equal #bj4 ,on comp>+ ,pr(essor ,rood's scales ( divisions ) ^? ( ! t9tometrical scales already describ$1 !y appe> to co9cide 9 sev]al p>ticul>s1 = in/ance3-- ,! mono*romes correspond bo? 9 numb] & 9 "n4 ,_! positions 9 ! scales correspond4 ,_! unit divisions are equal 9 numb]1 & 9 dim5sions4 ,_! col\r positions correspond1 :5 an artificial t9tometrical spectrum is made by regul>ly ov]lapp+ mono*romes4 ,x foll[s t :5 ! two scales are sup]impos$ z 9 ,plate ,v41 %[+ simil> mono*romes z ly+ 9 ! same p]p5dicul>1 ! same wave l5g? numb]s apply to bo?2 conc]n+ ! dim5sions betwe5 ! mono*romes1 ! spaces occupi$ by #gb1gaf wave l5g?s betwe5 ! spectrum mono*romes1 also repres5t simil> spaces 9 ! t9tometrical scales1 & "o-tw5tie? ( ?is #c1fce repres5ts ! space ( a s+le unit 9 ea* case4 ,9 connexion ) ^! co-relat$ dim5sions1 "s in=mation is obta9able be>+ on ! limitation ( a mono*romatic vision = discrim9at+ small col\r diff]5ces4 ,"u ord9>y daylight conditions1 ! unit 9 ! light] %ades ( ! t9tometrical scale is divid$ into #ajj fractional p>ts1 ea* fraction !re=e repres5ts a space occupi$ by ?irty-six wave l5g?s 9 ! spectrum scale4 ,?is may be ne> ! limit ( dim5sion = mono*romatic vision 9 su* a gradually *ang+ col\r scale1 z t ( ! spectrum1 & may be "s guide z to suitable slit areas 9 ! syn!tical build+ up ( complex col\r$ light4 ,illu/ration3 ,,plate ,,vi ,,six ,,col\r ,,*>ts ,,9 ,,"o ,,or ,,ano!r ,,( ,,:i* ,,any ,,simple ,,or ,,complex ,,col\r ,,f9ds ,a ,,def9ite ,,position4 ,to face page #ci4 ,lovibond1 ,col\r ,!ories4 ,9 ,plate ,,vi4 are %[n ! six t9tometrical col\r *>ts1 z ly+ 9 _! ord] on ! t9tometrical spectrum1 illu/rat+ t any measur$ col\r factor lies 9 a p]p5dicul> drawn ?r\gh bo? spectra1 & occupy+ ! same wave l5g? position1 & may !re=e be designat$ by t wave l5g? numb]4 ,?is explanation is n int5d$ to convey t ! col\r en]gies d n really ov]lap beyond ! b\nd>ies ( ! dual comb9ations1 b only t ! vision is unable to di/+ui% z col\r1 su* ov]lapp+ if x exi/s4 ,,po9ts ,,( ,,diff]5ce4 ,on fur!r comp>isons ( ! two scales !re are "s po9ts ( diff]5ce :i* h a be>+ on _! values z col\r /&>ds4 ,!re is a v>iation 9 ! l5g? ( ! two scales1 ! spectrum t]m9at+ at ,h1 :il/ ! t9tometrical scale is ext5d$ to a six? division 9 ! region ( ! ultra violet1 %[+ ov]lapp+ comb9ations ( ,r$ & ,violet1 /rictly analog\s to ! ov]lapp+ b9>ies 9 ! o!r five sections4 ,^! r$ & violet comb9ations con/itute "o-six? ( ! cycle ( di/+ui%able col\rs1 & _c be omitt$ 9 any sy/em ( col\r /&>dization1 !re=e _! abs5ce 9 ! cont9u\s spectrum is a drawback4 ,a second drawback1 is ! limit$ numb] ( spectrum complex col\rs1 9 consequ5ce ( ea* col\r be+ bl5d$ only ) ov]lapp+ col\r value1 :i* lies 9 its own wave l5g?1 :]eas 9 nature ea* col\r may be bl5d$ ) any value ( ! ov]lapp+ col\r4 ,9 ! t9tometrical /&>ds1 simil> effects are obta9$ by *ang+ ! value ( ! grad$ slips4 ,x is true1 t complex col\rs o!r ?an ^? 9 ! same wave l5g?1 may be develop$ by bl5d+ two col\rs f diff]5t p>ts ( ! spectrum1 b ! ray proportions ( col\rs s produc$1 are necess>ily m complex ?an ^? develop$ by specific absorption2 ! fir/ be+ a me?od ( syn!sis t[>ds complexity1 & ! second a me?od ( analysis t[>ds simplicity1 & al?\gh two col\rs s produc$ may be simil> 9 "n1 r$ = in/ance1 !y mu/ diff] 9 "*4 ,?is view may t5d to reconcile "s ( ! !oretical diff]5ces betwe5 ,sci5ti/s & ,arti/s4 ,,! ,,ultra ,,violet ,,division4 ,! complete range ( daylight col\rs n be+ fully compris$ 9 a cont9u\s spectrum1 may be consid]$ z a cycle ( radiant en]gies1 s5sitive to ! vision z col\r1 :i* c be repres5t$ z a circle z 9 ,plate ,,vii4 ,! out] & brok5 circle repres5ts a b5t spectrum1 ! unoccupi$ division correspond+ 9 position ) t ( ! r$ & violet mixtures 9 ! complete cycle4 ,?is arrangem5t does n alt] ! relative positions ( ! ,fraunhop] l9es ,a1 ,b1 ,c1 ,d1 ,e1 ,f1 ,g & ,h 9 ref]5ce to ei!r scale1 b1 x !oretically breaks t sequ5ce ( ! successive wave l5g?s 9 ! ,r$ ,violet :i* holds good 9 ! o!r five divisions f ,a to ,h4 ,illu/ration3 ,,plate ,,vii ,to face page #dj4 ,lovibond1 ,col\r ,!ories4 ,9 ord] to !oretically avoid ?is juxtaposition ( wave l5g? contra/1 x is only necess>y to imag9e t ! violet en]gy beyond ,h 9 ! ultra violet1 is ov]lapp$ by ! infra r$ en]gy ( a succe$+ spectrum1 fill+ ?is section ) a s]ies ( ov]lapp+ b9>ies analog\s 9 wave l5g? sequ5ce to t ( ! o!r sections4 ,a ,,residual ,,r$ ,,ray4 ,ap>t f ! col\rs ( ev]yday life !re is1 9 sunlight & mo/ direct artificial lights1 an additional r$ en]gy :i* diff]s mat]ially f ! r$ en]gy 9 diffus$ daylight4 ,x 0 fir/ notic$ :il/ e/abli%+ ! col\r equival5ce ( ! t9tometrical light unit1 by develop+ a r$ s5sation :i* di/urb$ con/ancy ( read+ "u c]ta9 conditions ( light4 ,s f> z ! writ] kn[s1 ?is en]gy has nev] be5 inve/igat$ z sep>ate f ! o!r spectrum r$4 ,! foll[+ obs]vations mu/ be consid]$ z t5tative only4 ,,"s ,,prop]ties4 ,x does n obey ! laws ( absorption :i* gov]n ! r$ ( diffus$ daylight4 ,:5 ! six transp>5t pigm5t>y col\rs are illum9at$ by direct sunlight1 & view$ ?r\gh a suffici5t numb] ( ,neutral ,t9t units1 ! col\rs all disappe>1 all appe>+ r$ alike1 ) only diff]5ces 9 lum9osity4 ,! spectrum position ( ?is r$ en]gy is 9 ! ,a4 ,b4 region1 & fur!r int]ception by ,neutral ,t9t :il/ n>r[+ ! b&1 int5sifies ! col\r1 until ob/ruct$ by ! l>ge numb] ( int]cept+ glass surfaces4 ,x has no photographic action on ! six s5sitis$ pap]s dealt ) 9 ! photographic section4 ,,light ,,int5sities4 ,! app>atus = det]m9+ ! unit values ( light int5sities 9 ! foll[+ s]ies ( measurem5ts1 consi/$ ( a conical rectangul> hopp] tap]+ f #b feet to #b in*es squ>e4 ,?is 0 adapt$ s t ! light f ! small end1 comm&$ ! /age ( ! optical in/rum5t suffici5tly close to cut (f outside light4 ,! wide end fac+ a nor? sky 0 adapt$ ) slid+ %utt]s1 to regulate ! area ( incid5t light2 ( ! six wat]-col\r pigm5ts :i* ne>e/ correspond$ to ! /&>d col\rs1 wa%$ to _! full dep? on ,:atman's pap]1 six measurem5ts 7 made4 ,^! measurem5ts are %[n 9 ,table ,,iv1 & classifi$ 9 ,table ,v4 ,x w be not$ t ! read+s are con/ant = all ! col\rs betwe5 #af & #bf units1 except a v>iation ( light #ae 9 ! #bd-;in* op5+1 :i* is 9 effect z if ! cone 0 n pres5t1 & #b 9 ! #h-;in* area ( orange4 ,note4--,exp]im5ts 9 ?is bran* give "s in=mation relat+ to ! p]ception ( col\r "u daylight conditions1 by limit+ ! range ( int5sities )9 :i* col\r c be di/+ui%$ & diff]5tiat$1 :il/ _! sep>ate photographic action 7page #dh7 sugge/s ! impression t col\r ph5om5a1 outside ^! limits1 may be a physiological expression ( widely v>y+ und]ly+ en]gies4 ,,table ,,iv4 ---------------------------------------- ------------------------ ,squ>e ,pigm5t4 ,in*es ,light ,black4 ,r$4 ,orange4 ,ap]ture4,int5sity4 ---------------------------------------- ------------------------ ,c>m9e #b #aj #e #bjb #c ---- #d #aa #e #aia #d ---- #f #ad #df #ahie #ei ---- #h #af ---- #afi #aa ---- #aj #bj ---- #afi #aa ---- #ab #bb ---- #afi #aa ---- ,op5 #bf ---- #afi #aa ---- ---------------------------------------- ------------------------ ,yell[ ,lemon ,yell[ #b #aj ---- #fi #a ---- #d #aa ---- #fi #a ---- #f #ad ---- #fi #a ---- #h #af ---- #gj ---- ---- #aj #bj ---- #gj ---- ---- #ab #bb ---- #gj ---- ---- ,op5 #bf ---- #gj ---- ---- ---------------------------------------- ------------------------ ,blue4 ,violet4 ,cobalt ,blue #b #aj ---- #aae ---- ---- #d #aa ---- #aae ---- ---- ,gre54 #f #ad ---- #ajg #b ---- ,violet4 #h #af ---- #aje #e ---- #aj #bj ---- #aje #e ---- #ab #bb ---- #aje #e ---- ,op5 #bf ---- #aje #e ---- ---------------------------------------- ------------------------ ,r$4 ,orange4 ,light4 ,*rome ,orange #b #aj ---- #cd #fj ---- #d #aa ---- #cd #fj ---- #f #ad ---- #cj #fb ---- #h #af ---- #cj #fj #je #aj #bj ---- #cb #fj #je #ab #bb ---- #cb #fj #je ,op5 #bf ---- #cb #fj ---- ---------------------------------------- ------------------------ ,yell[4 ,gre54 ,em]ald ,gre5 #b #aj ---- #b #fd #je #d #aa ---- ---- #fd #je #f #ad ---- ---- #fd #je #h #af ---- ---- #ff #bj #aj #bj ---- ---- #ff #bj #ab #bb ---- ---- #ff #bj ,op5 #bf ---- ---- #ff #je ---------------------------------------- ------------------------ ,r$4 ,violet4 ,mauve #b #aj ---- #cj #gd ---- #d #aa ---- #cj #gd ---- #f #ad ---- #cj #gb ---- #h #af ---- #bh #gb ---- #aj #bj ---- #bh #gb ---- #ab #bb ---- #bh #gb ---- ,op5 #bf ---- #bh #gb ---- ---------------------------------------- ------------------------ ,,table ,v4 ,,col\r$ ,,surfaces ,table ( ,v>y+ ,lum9\s ,int5sities ---------------------------------------- ----------------- ,r$4 ,yell[4 ,blue4 ---------------------------------------- ---- ,in*es ,light 8,c>m9e40 8,lemon40 8,cobalt40 ,squ>e4,units4 --------------------------------------- ,r4 ,or4 ,blk4 ,y4 ,or4 ,b4 ,vi4 ,blk4 ---------------------------------------- ------------ #b #aj #bjb #c #e #fi #a #aae ---- ---- #d #ad #aia #d #e #fi #a #aae ---- ---- #f #ad #ahie #ei #df #fi #a #ajg #b #a #h #af #afi #aa ---- #gj ----#aje #e ---- #aj #bj #afi #aa ---- #gj ----#aje #e ---- #ab #bb #afi #aa ---- #gj ----#aje #e ---- ,op5 #bd #bf #afi #aa ---- #gj ----#aje #e ---- ---------------------------------------- ----------------- ---------------------------------------- ----------------- ,orange4 ,gre54 ,violet4 ---------------------------------------- ---- ,in*es ,light 8,*rome40 8,em]ald40 8,fr4 ,mauve40 ,squ>e4,units4 --------------------------------------- ,or4 ,r4 ,light4 ,gr4 ,y4 ,light4 ,vi4 ,r4 ---------------------------------------- ------------ #b #aj #f #cd #je #fd #b #je #gd #c #d #ad #f #cd #je #fd #b #je #gd #c #f #ad #fb #c #je #fd---- #je #gb #c #h #af #f #c ---- #ff---- #b #gb #bh #aj #bj #f #cb ---- #ff---- #b #gb #bh #ab #bb #f #cb ---- #ff---- #b #gb #bh ,op5 #bd #bf #f #cb ---- #ff---- #je #gb #bh ---------------------------------------- ----------------- ,,*apt] ,,xii4 ,! ,physiological ,light ,unit4 ,,diffus$ ,,light4 ,! physiological values ( light int5sities det]m9$ by ! absorptive me?od1 diff] 9 "s respects1 f ! int5sities bas$ on ! inv]se ratio ( ! squ>es ( di/ance betwe5 ! %ad[s ( two lights4 ,h[ev] valuable ?is me?od ( calculat+ light int5sities may be f a ma!matical po9t ( view1 x does n express ! physiological appreciation ( light diff]5ces4 ,! dim5sions ( ! light unit us$ 9 ! foll[+ exp]im5ts h already be5 describ$4 ,?is me?od _c deal exhau/ively ) int5se direct lights1 on acc\nt ( ! pres5ce 7activity7 ( ! di/urb+ r$ ray :i* prev5ts total absorption4 ,su* lights mu/ fir/ be modifi$ by int]cept+ m$ia ( kn[n diffusive value1 or by reflection f a :ite surface4 ,"o object ( ^! exp]im5ts 0 to obta9 m insight into ! physiological conditions ( light1 z be>+ on ! "q ( /&>dization4 ,! fir/ two exp]im5ts are records ( int5sity *anges by "t1 9 ,morn+ & ,ev5+ light1 & are ( int]e/1 z be>+ on ! l[e/ lum9osities = read+1 = view+ objects at diff]5t di/ances1 & = def9+ ! limits at :i* col\rs visually disappe>4 ,! measurem5ts are m>k$ 9 neutral t9t units & plott$ 9 curves 9 ,*>ts #a & #b4 ,! numb]s on ! s+le curve 9 ! ,morn+ *>t repres5t total absorption ( ! direct light #bj degrees above ! horizon4 ,! upp] curve 9 ! ,ev5+ *>t also repres5ts ! direct light1 :il/ ! "u curve repres5ts ! light values z reflect$ f a lime sulphate surface2 except 9 ! case ( ! read+ notes :5 x repres5ts ! pr9t$ pap] surface4 ,! diff]5ce betwe5 ! two curves is ! loss ( light incid5t on reflection1 b ?is mu/ n be rigidly int]pret$ = all cases1 z !re is reason = suppos+ x v>ies ) diff]5t lights4 ,,direct ,,lights4 ,9 measur+ ! physiological int5sity ( direct lights1 ! pres5ce 7activity7 ( ! unabsorbable r$ ray1 prev5ts _! be+ dealt ) directly by ! absorptive me?od4 ,su* lights c1 h[ev]1 be made measurable by a suffici5t diffusion1 z already expla9$ 9 ! case ( direct sunlight1 ! proportion ( diffusion requir$1 be+ m or less accord+ to ! int5sity ( ! light2 9 ! foll[+ examples1 "o reflection f a :ite surface or f ! ord9>y grease spot arrangem5t1 0 f\nd to be suffici5t4 ,note4--,light reflect$ f grease is n above suspicion1 x be+ gov]n$ by ! law ( specific absorption already dealt )4 ,illu/ration3 ,*>t #a4 ,ev5+ ,light ,m>* #ah?4 #aijf4 ,upp] ,curve #bj above ,horizon ,l[] ,curve z ,reflect$ f a #a ,foot ,squ>e ,lime ,sulphate ,scre5 ,illu/ration3 ,*>t #b4 ,morn+ ,light ,decr4 #ag?4 #aijg4 #bj above ,horizon ,illu/ration3 ,*>t #c4 ,lum9\s ,int5sities ( #a1 #b #c ,/&>d ,c&les4 ,illu/ration3 ,*>t #d4 ,lum9osity ( ,gas f ,burn] ,r$uc$ to ,equal #a1 #b #c ,c&les at #a ,foot4 ,illu/ration3 ,*>t #e4 ,lum9osities ( ,p>aff9 ,lamp ,r$uc$ to #a1 #b #c ,c&les at #a ,foot4 ,! exp]im5ts 7 c>ri$ out on a home-made twelve-foot photomet]1 ) ! usual protect$ lant]n at ea* end1 "o be+ remov$ = pres5t purposes4 ,! grease spot c>ri] 0 replac$ by a "o-foot squ>e diaphragm1 ) a /&>d :ite surface2 ?is travell$ ! :ole l5g? ( ! photomet] at "r angles to ! light1 & ! read+s made at "o-foot int]vals at an angle ( #de degrees1 #aj in*es di/ance f ! :ite surface4 ,*>ts #c1 #d & #e deal ) exp]im5ts1 ) "o1 two & ?ree /&>d c&les ( ! ,london ,gas ,ref]ees4 ,! curves repres5t ! physiological rate ( decl9+ lum9osities by di/ance4 ,"s *>act]i/ic diff]5ces f o!r lights are br\ght toge!r 9 ,*>ts #d & #e4 ,! slight irregul>ities 9 ! curves are probably due to ! read+s be+ made at half unit int]vals4 ,^! act+ sometimes 9 opposite directions1 fully acc\nt = want ( symmetry 9 ! curves4 ,a noticeable feature 9 ^! exp]im5ts is ! small am\nt ( physiological lum9osity add$ by ea* successive c&le to ! fir/4 ,!oretically1 if "o c&le equals #ba units int5sity1 two %\ld equal #db1 & ?ree #fc1 :]eas ! physiological additions ( lum9osity are n only mu* less1 b v>y ) diff]5t lum9\s int5sities1 z w be se5 by ! foll[+ comp>isons3-- #a #b #c ,c&le ,c&les ,c&les ,total4 ,!oretical #ba #ba #ba #fc ,physiological #ba #c #f #cj ,*>t #d repres5ts ! ,lum9osity ( gas f a batsw+ burn] r$uc$ to "o1 two & ?ree c&le p[] at "o foot di/ance4 #a #b #c ,c&le ,c&les ,c&les ,total4 ,!oretical #ba #ba #ba #fc ,physiological #ba #c #g #ca ,*>t #e repres5ts ! ,lum9osity ( a h& ,p>aff9 ,lamp simil>ly r$uc$4 #a #b #c ,c&le ,c&les ,c&les ,total4 ,!oretical #ba #ba #ba #fc ,physiological #ba #c #f #cj ,,photographic ,,en]gies ,,( ,,diff]5t ,,rays ,! foll[+ exp]im5ts are prelim9>y only1 & 7 und]tak5 to det]m9e ! relation%ip ( ! sev]al col\rs ( ! t9tometrical scales1 to _! associat$ photographic values1 "u diff]5t conditions ( light & times ( exposure1 ! end 9 view be+ ! hope ( /&>diz+ scre5s1 pap]s & impressions4 ,! /&>diz$ col\rs act z selective light absorb5ts on ! same pr9ciple z scre5s = tri*romatic col\r "w1 b diff] f ^! 9 _! hav+ a def9ite /&>d ( col\r dep? & col\r purity4 ,"w ( ?is "* requires pap] ( a kn[n degree ( s5sitiv5ess1 b on inquiry x 0 f\nd t no reliable /&>d _h z yet be5 e/abli%$4 ,on ?is1 six makes ( 8:ite0 pap] 7 pur*as$ 9 ! op5 m>ket & submitt$ to exposures "u ! foll[+ conditions3-- ,six slips ( ! s5sitiz$ pap]s 7 cov]$ by a ?9 metal plate1 pi]c$ by six r[s ( ap]tures1 a complete r[ ly+ ov] ea* sample ( pap]4 ,! r[s conta9$ sev5 ap]tures ea*1 "o be+ left uncov]$ to receive ! full en]gy ( ! imp++ light4 ,! rema9+ six 7 cov]$ respectively by a ,r$1 ,orange1 ,yell[1 ,gre51 ,blue or ,violet /&>diz$ scre5 ( #ae units col\r int5sity2 ! :ole 0 fitt$ into a suitable exposure frame4 ,_m exposures 7 made1 f :i* ! f\r foll[+ 7 select$3-- ,no4 #a4 #bj m94 exposure to a dull sky4 #b4 #aj bright sunlight4 #c4 #bj #d4 #cj ,! results are arrang$ 9 ,tables ,,vi & ,,vii4 ,table ,,vii conta9s results ( diff]5t exposures "u sunlight conditions4 ,,table ,,vi4 ,,dull ,,s\? ,,light4 #bj ,m9utes' ,exposure on ,:ite ,s5sitiz$ ,pap]s4 ---------------------------------------- ----------------- ,pap- ers ,,op5 ,,scre54 ,,r$ ,,scre54 ,,orange ,,scre54 ---------------------------------------- ----------------- ,blk4 ,or4 ,r$4 ,blk4 ,or4 ,yel4 ,blk4 ,or4 ,r$4 #a #gh #db #fj #bj #dh #cj ---- #c #b ,r$4 #b #fj #ej #ee #ai #ca #d ---- ---- ---- ,yel4 #c #gh #cb #gj #bg #dg #cj ---- ---- ---- ,r$4 #d #gb #dc #fj #bb #cb #b ---- ---- ---- #e #eh #gb #dj #ai #bc #h ---- ---- ---- #f #ef #gd #dj #ah #bf #f ---- ---- ---- ---------------------------------------- ----------------- ---------------------------------------- ---------------------------------- ,pap- ers ,,yell[ ,,scre54 ,,gre5 ,,scre54 ,,blue ,,scre54 ,,violet ,,scre54 ---------------------------------------- ---------------------------------- ,blk4 ,or4 ,r$4 ,blk4 ,or4 ,r$4 ,blk4 ,or4 ,r$4 ,blk4 ,or4 ,r$4 #a #bj #cj #af ---- ---- ---- #ci #gf #ce #b #d #aj ,yel4 #b #d #d #aj ---- ---- ---- #dc #ib #de #b #h #h ,r$4 #c #ab #e #h ---- ---- ---- #cg #ic #bj #g #f #i ,yel4 #d #ab #a #ab ---- ---- ---- #cd #aa #aj #g #g #i #e #aj #c #c ---- ---- ---- #cc #hg #bj #c #c #ab ,r$4 #f #b #c #d ---- ---- ---- #cf #hi #ae #d #b #i ---------------------------------------- ---------------------------------- ,,table ,,vii4 ,,bright ,,sunlight 7,s\?71 #ah--i--ab4 #aj ,m9utes' ,exposure on ,:ite ,s5sitiz$ ,pap]s4 -------------------- ------------------------------------- ,,no4 ,,op5 ,,scre54 ,,r$ ,,scre54 ,,orange ,,scre54,,yell[ ,,scre54 ---------------------------------------- ------------------ ,blk4 ,or4 ,r$4,blk4 ,or4 ,yel4,blk4 ,or4 ,r$4,blk4 ,or4 ,r$4 #a #hd #af #febh #fh #ai #cd #ada #ee #bc #ga -- #b #hb #bj #fcbg #dg #cf-- -- -- #h #ai #gj #c #gh #bb #gebd #gj #da-- -- -- #bd #db #hj #d #gh #af #hfbd #ed #cb-- -- -- #ae #bc #gj #e #fd #dd #ggbd #eb #cj-- -- -- #i #ah #hj #f #eb #fc #eebc #ea #cj-- -- -- #aa #bj #hj ,,bright ,,sunlight 7,s\?71 #ah--i--ab4 #bj ,m9utes4 ,vio4 ,r$4 ,or4 ,r$4 ,or4 ,yel4 ,r$4 #a #ajf #ad #ejgj #bb #hcaa #cf #i #ajj -- #gj ,r$4 ,or4 #b #ajj -- #hgj #bf #gd-- #aj #c #gd #bj #cf ,or4 #c #ib #af #bbde #ee #hjah #gd -- #eb #db #ha ,or4 #d #ajf #d #cefj #db #hc #dd #acf #h #ij #be #ej #e #ajj #h #egfb #dj #hc-- #g #de #gj #ej #dj #f #fb #df #ggej #ge #dj #b #d #e #ed #ga #de ,,bright ,,sunlight 7,s\?71 #ah--i--ab4 #cj ,m9utes4 ,or4 ,r$4 ,or4 ,r$4 ,or4 ,r$4 ,or4 ,r$4 #a #ajf #i #aefd #dd #egbf #gh #aa #eb #cd #ajd #b #ib #ad #bifb #ec #ee #a #g #d #gh #cj #eb #c #ajh #ab #aegb #cd #hd #g #bj #b #ib #af #eb #d #ajj #bj #aefb #dd #fi #e #aj #g #hb #bj #gc #e #if #dd #deeh #ej #gb #b #ai #g #fb #ch #fe #f #ff #gi #ejdh #gb #ej #b #e #ee #ej #ge #bj ---------------------------------------- ------------------ ,,bright ,,sunlight 7,s\?71 #ah--i--ab4 #aj ,m9utes' ,exposure on ,:ite ,s5sitiz$ ,pap]s4 ---------------------------------------- ---- ,,no4,,gre5 ,,scre54 ,,blue ,,scre54,,violet ,,scre54 ---------------------------------------- ---- ,blk4 ,or4 ,r$4,blk4 ,or4 ,r$4,blk4 ,or4 ,yel4 #a #bf #fi #ajeb #dd #hd #age #cfe #dj #b -- #ae #jcfj #ch #fg #ag #ci #dj #c #bb #jb #jdef #ei #fe #ae #ce #ab #d #ai #je #abdh #ef #ff #ac #cb -- ,r$4 #e -- -- -- #dj #aje #bj #f #ag #aj #f -- -- -- #dj #aae #aj #e #ai #aa ,,bright ,,sunlight 7,s\?71 #ah--i--ab4 #bj ,m9utes4 ,or4 ,yel4 ,or4 ,r$4 ,or4 ,r$4 #a #ca #fa #ah #hj #bj #he #de #ge #de ,or4 #b #ai #cg #h #hh #f #cf #ej #fe #de #c #aj #gj #af #hf #ad #ce #dj #he #de #d #ah #dh #ab #hj #bb #fh #de #ge #de #e #ag #di #ad #gf #bd #hj #dj #he #dj ,r$4 #f #ah #cd #d #fd #dd #hb #ce #he #aj ,,bright ,,sunlight 7,s\?71 #ah--i--ab4 #cj ,m9utes4 ,or4 ,yel4 ,or4 ,r$4 ,or4 ,r$4 #a #aj #fh #b #fd #bf #ge #db #fh #fj #b #ah #cd #b #hd #h #ch #ed #ha #aj #c #bb #eb #bb #hj #bj #ge #de #he #dj #d #be #dg #bj #hj #af #gd #cg #ajc #aj ,yel4 #e #af #db #bh #gf #bf #fh #ca #id #ae #f #ae #ci #b #fd #gf #ee #cd #ig #ae ---------------------------------------- ---- ,x w\ld be unsafe to draw def9ite conclusions f a few exp]im5ts1 b s f> z p]missible1 ! results %[ consid]able diff]5ces1 bo? 9 dep? & 9 col\r1 ( ! en]gy ( ! diff]5t rays1 = in/ance-- ,comp>e ,nos4 #a & #f "u #bj m94 sunlight4 ,black4 ,orange4 ,r$4 ,no4 #a #ajf #ad #ej ,no4 #f #fb #df #gg or aga9 #c & #f1 ! maximum & m9imum1 "u #cj m94 exposure4 ,black4 ,orange4 ,r$4 ,no4 #c #ajh #ab #ae ,no4 #f #ff #gi #ej ,! s5sitiv5ess ( ,nos4 #b1 #d & #e appe>s to h be5 exhau/$ by #bj m94 exposure to sunlight1 fur!r exposure %[+ no reaction2 :il/ ! s5sitiv5ess ( ,nos4 #a1 #c & #f d n appe> to h be5 exhau/$ by #cj m94 sunlight exposure4 ,o!r noticeable po9ts are ! small action "u ! ,orange1 ,gre5 & ,violet scre5s1 & ! great]1 al?\gh v>iable proportion ( col\r to black "u all ! col\r scre5s4 ,,tri*romatic ,,col\r ,,scre5s4 ,table ,,viii conta9s ! col\r measurem5ts ( five sets ( scre5s = tri*romatic col\r "w :i* h come f "t to "t "u ! writ]'s notice4 ,! measurem5ts are ! t9tometrical col\r units requir$ to mat* ! scre5s "u daylight conditions1 & are classifi$ "u ! !oretically accept$ t]ms ( ,r$1 ,gre5 & ,violet4 ,,table ,,viii4 ---------------------------------------- ---------------------------------- ,set4 ,,r$ ,,scre5s4 ,,gre5 ,,scre5s4 ,,violet ,,scre5s4 ---------------------------------------- ---------------------------------- ,no4 ,r$4 ,or4 ,vi4 ,light4 ,yel4 ,gre54 ,or4 ,light4 ,blue4 ,gre54 ,black4 #a #aaij ---- ---- #af #bgj #cfj ---- #ij #cbj #ad #ff #b #bdb #h ---- ---- #hi ---- #a ---- #acj ---- #ca #c #bfd ---- #h ---- #ge ---- #ad ---- #aff ---- #cb #d #bbf ---- ---- ---- #gf ---- #ad ---- #aec ---- #ca #e #baj ---- #ij ---- #bhj #adj ---- ---- #bhj ---- #bh ---------------------------------------- ------------------------------------ ,! ,r$ scre5s are all practically pure except ,no4 #e1 :i* transmits also #cj p] c5t4 ,violet4 ,no4 #a is di/+ui%$ by its great] col\r dep? & purity1 ! degree ( :i* latt] is record$ at #af light units bright] ?an /&>d4 ,9 ! ,gre5 division1 only ,nos4 #a & #e transmit any gre51 ,no4 #a transmitt+ also #dbh p] c5t4 yell[ & be+ #ij units bright] ?an /&>ds2 ,no4 #d transmits #fff p] c5t4 yell[ to #ccc p] c5t4 gre52 ,nos4 #b1 #c & #d are all yell[s t+$ ) orange4 ,9 ! ,violet division1 ,nos4 #b1 #c1 #d & #e are all pure blues2 ,no4 #a is t+$ ) gre54 ,app5dix ,i ,,col\r ,,education ,! "t has pass$ :5 x might h be5 consid]$ necess>y to preface a h&book on ! tea*+ ( col\r by argum5ts to prove t x is a legitimate subject ( in/ruction 9 s*ools1 b x has n hi!rto be5 suffici5tly recogniz$ t ! e>ly /ages ( su* in/ruction mu/ be on s\nd l9es & t no?+ mu/ be taught :i* w aft]w>ds h to be unle>n$4 ,ap>t f ! pleasure its s5sations give to all prop]ly con/itut$ p]sons1 ! /udy ( col\r has an intellectual value 9 common ) o!r bran*es ( sci5ce4 ,x /r5g!ns ! judgm5t by con/antly requir+ ?\ght & precision 9 def9ition1 x also develops ! faculty ( col\r p]ception ev5 to ! po9t ( cur+ "s =ms ( col\r bl9dness4 ,9 addition to ?is1 x =ms a necess>y "p ( ! in/ruction 9 all s*ools 9 :i* draw+ is prop]ly taught by me?ods :i* dem& f ! pupils fai?ful repres5tations ( ! appe>ances ( actual objects 9 col\r z !y are se54 ,9 ! pa/ ! sy/ematic /udy ( col\r has be5 m or less neglect$ f two pr9cipal causes3 fir/1 ! want ( a compreh5sive s*eme ( col\r nom5clature capable ( describ+ all col\rs 9 t]ms precise en\gh = g5]al und]/&+ & record2 &1 second1 ! abs5ce ( any reliable means ( reproduc+ any specific col\r if lo/ or fad$4 ,bo? ^! conditions may n[ be secur$ by ! use ( ! /&>diz$ col\r$ glasses suppli$ ) ! ,col\r ,educator1 & ?is "w is int5d$ to br+ ! subject be=e tea*]s 9 su* a way z to make ea* po9t p]fectly easy ( demon/ration to a class 9 a sy/ematic mann]4 ,to-day ! value & importance ( a ke5 p]ception ( col\r & ( an app>atus furni%+ def9ite col\r /&>ds1 ?\gh p]haps n mu* appreciat$ by ! g5]al public1 are widely recogniz$ 9 ! indu/rial & sci5tific _w2 & x is evid5t t 9 ^! days ( ke5 comm]cial competition betwe5 nations we _c af=d to neglect any means :i* w enable u to ma9ta9 pres5t indu/ries & to develop new ones4 ,g5]al ,rem>ks4--,x is n advisable to introduce col\r !ories to pupils be=e !y "k ! names ( ! diff]5t col\rs1 b1 z ! glasses us$ 9 ! app>atus are grad$ = col\r-dep? accord+ to a set ( scales n[ g5]ally accept$ z ( /&>d value1 a %ort description ( ! d]ivation ( ! col\r names w be ( s]vice :5 ! pupils are suffici5tly advanc$4 ,! names ( ! six spectrum col\rs1 ,r$1 ,orange1 ,yell[1 ,gre51 ,blue1 & ,violet1 are accept$ by common cons5t z describ+ ! pr9cipal hues into :i* a beam ( :ite light c be resolv$ by a diffraction grat+ or by prismatic refraction4 ,!y are also ! col\rs di/+ui%able 9 objects ( ev]yday life1 & ! foll[+ ,educational ,me?od is bas$ on ! fact t !y c be sep>at$ at w f ord9>y daylight4 ,!re=e ! fir/ educational /ep is to associate ^! six col\r rays ) _! respective names1 ! pupils be+ made to und]/& t !re are _m degrees ( dep? 9 ea* col\r4 ,! ,applications ( ,col\r to ! ,"w ( ,ev]yday ,life are s univ]sal t a complete li/ is almo/ impossible1 ?\gh "s ( ! mo/ important are m5tion$ bel[4 ,9 a g5]al way ! visual *>act]i/ics ( e visible object are det]m9$ by contra/s ( light & col\r1 outl9e itself be+ gov]n$ by diff]5ces ( light int5sity4 ,9 ,nature1 col\r is practically univ]sal4 ,!re are few objects p]fectly :ite4 ,mo/ ( !m h col\r ( great] or less complexity2 ev5 sn[ "u a cl\dless sky has a blue t9t :i* is measurable aga9/ su* :ite objects z pure lime sulphate1 z9c :ite1 etc41 ! blue t9t be+ manife/ly reflect$ f ! cl\dless sky1 z x disappe>s "u a cl\dy ov]ca/4 ,"s ( ! ,sci5tific ,applications ( ,col\r4--,x associates col\r s5sations ) def9ite names & values2 discov]s & classifies cases ( col\r-bl9dness1 & is a prep>ation = ! physical /udy ( light4 ,x is also ess5tial = /udy+ ! physiological /ructure ( ! organs ( vision1 = disclos+ abnormal conditions ( ! blood1 & = measur+ ! col\r ( ! hair & sk9 = ! an?ropological classification ( races4 ,x is us$ 9 g5]al laboratory "w = analytical & orig9al inve/igation2 & x furni%es /&>ds ( value = ! petroleum indu/ry1 ! ,int]national ,tann+ ,association1 ! int]-,/ates ,cotton ,se$ ,oil ,association1 etc4 ,x is also "o ( ! pr9cipal factors 9 all arti/ic indu/ries2 =1 besides hav+ an important educational value 9 que/ions ( h>mony1 contra/1 & ta/e1 x is ( direct comm]cial value 9 su* indu/ries z dye+1 calico pr9t+1 all wooll5 indu/ries1 wall-pap] pr9t+1 pa9t mak+1 h\se decoration1 etc4 ,g5]al ,in/ructions = ,us+ ! ,app>atus4--,! app>atus consi/s ( a frame hav+ six little w9d[s1 fitt$ ) slid+ %utt]s1 & a tray conta9+ eighte5 /&>diz$ glasses4 ,! frame mu/ be plac$ on a table or /& fac+ ! *ildr51 ) a w9d[ or "s o!r s\rce ( diffus$ :ite light beh9d x4 ,c>e mu/ be tak5 n to h a col\r$ backgr\nd ( any k9d4 ,! glasses are 9 ?ree col\rs1 ,r$1 ,yell[1 & ,blue1 ( diff]5t dep?s4 ,! dep? ( col\r is m>k$ 9 figures on ea* glass1 & correspond+ numb]s 9 ! ?ree col\rs are ( equal int5sity4 ,x is ( importance t ! six spectrum col\r t]ms %\ld be ! only ones us$ 9 ! prelim9>y /ages4 ,! fir/ /ep 9 col\r tea*+ mu/ be to develop & tra9 ! p]ceptive faculties ( ! *ildr5 s z to enable !m to express 9 words ! col\r s5sations :i* are excit$4 ,= ?is purpose x is necess>y to beg9 by demon/rat+ t ! six spectrum col\rs ,r$1 ,orange1 ,yell[1 ,gre51 ,blue1 & ,violet1 are d]iv$ f :ite light4 ,r$1 ,yell[1 & ,blue %\ld fir/ be dealt )1 & = practical "w ea* pupil %\ld be suppli$ ) ?ree wat]-col\r pigm5ts closely correspond+ 9 hue to ! /&>diz$ glasses1 viz41 ,crimson ,lake1 ,lemon ,yell[1 & ,cobalt ,blue2 also ) a piece ( :ite pap] rul$ into six small rectangul> spaces correspond+ to ! little w9d[s ( ! app>atus4 ,z ea* col\r is demon/rat$ by means ( ! glass 9 ! app>atus1 ea* pupil %\ld pa9t ! correspond+ pigm5t 9 its prop] place on ! pap]4 ,! little %utt]s be+ plac$ 9 all ! six little w9d[s1 remove ! top left-h& %utt] & ins]t a deep ,r$ glass1 ?us %[+ ,r$4--,! pupils w "n ?is & !n pa9t ! correspond+ col\r on _! pap]s4 ,next1 remove ! %utt] bel[ ! fir/ "o1 & ins]t a ,yell[ glass ( ! same num]ical value z ! ,r$ "o1 ?us %[+ ,yell[4--,! pupils w "n ?is & !n pa9t ! correspond+ col\r on _! pap]s4 ,n[ remove ! %utt] next bel[ & ins]t a ,blue glass ( ! same num]ical value z ! ,r$ & ,yell[ ones1 ?us %[+ ,blue4--,! pupils w "n ?is & !n pa9t ! correspond+ col\r on _! pap]s4 ---------------- #a ,,r$ ---------------- #b ,,yell[ ---------------- #c ,,blue ---------------- ,!re are n[ expos$ to view ! ?ree col\rs :i* are by arti/s commonly call$ prim>ies1 b x w be f\nd conv5i5t to t]m ,r$1 ,yell[1 & ,blue ! ,dom9ant col\rs ( ?is sy/em4 ,! second /ep is to %[ h[ ! ?ree second>y or subord9ate col\rs are d]iv$ or develop$4 ,remove ! top "r-h& %utt] & ins]t a deep ,r$ & a deep ,yell[ glass ( equal dep?1 %[+ ! pupils t ^! two col\rs comb9$ 9 equal proportions develop ,orange4--,! pupils w "n ?is1 & w !n mix _! ,r$ & ,yell[ pigm5ts to obta9 a simil> ,orange :i* w be pa9t$ 9 its prop] place on _! pap]s4 ,n[ remove ! %utt] next bel[ & ins]t a deep ,yell[ & a deep ,blue glass ( equal dep?1 %[+ ! pupils t ^! two col\rs comb9$ 9 equal proportions develop ,gre54--,! pupils w "n ?is1 & w !n mix _! ,blue & ,yell[ pigm5ts to obta9 a simil> ,gre5 :i* w be pa9t$ 9 its prop] place on _! pap]s4 -------------------- #a #d ,,r$ ,,orange -------------------- #b #e ,,yell[ ,,gre5 -------------------- #c #f ,,blue ,,violet -------------------- ,remove ! la/ "r-h& %utt] & ins]t a deep ,r$ & a deep ,blue glass ( equal dep?1 %[+ t ^! two col\rs comb9$ 9 equal proportions develop ,violet4--,! pupils w "n ?is1 & mix _! ,blue & ,r$ pigm5ts to obta9 a simil> ,violet1 :i* w also be pa9t$ 9 its prop] place on _! pap]s4 ,n[ are expos$ to view on ! left-h& side ! ?ree prim>y or dom9ant col\rs1 & on ! "r-h& side ! ?ree second>y or subord9ate col\rs1 & ! :ole frame is fill$ ) ! six spectrum col\rs 9 equal col\r dep?4 ,correspond+ to ! col\rs 9 ! frame1 ea* pupil's pap] %\ld %[ a simil> arrangem5t ( col\rs1 & ! pupils c be taught _! spectrum ord] by read+ !m 9 r[s horizontally--,r$1 ,orange1 ,yell[1 ,gre51 ,blue1 & ,violet4 ,! tea*] %\ld n[ take out ! col\r$ glasses & replace ! %utt]s1 except ! two top w9d[s1 "o ( :i* is left op5 to %[ :ite light1 & ! o!r fill$ ) ?ree equally deep glasses 9 ,r$1 ,yell[1 & ,blue1 %[+ ei!r black or neutral grey1 & demon/rat+ ! total or p>tial absorption ( light accord+ to _! high] or l[] num]ical unit value4 ,x is ( ! utmo/ importance to be> 9 m9d t ! glasses are grad$ = diffus$ daylight1 & t all artificial lights are m or less col\r$ & w\ld give a diff]5t effect4 ,! same rem>k applies to light tak5 direct f col\r$ objects4 ,9 ?is set ! six w9d[s are 9 "o horizontal l9e1 & %\ld be uncov]$ 9 ! foll[+ ord]3 ,no4 #a ,w9d[ = ,r$4 ,dom9ants #c ,yell[4 #e ,blue4 #b ,orange4 ,subord9ates #d ,gre54 #f ,violet4 ,"o advantage 9 ?is me?od is t :5 all ! col\rs are 9 !y are arrang$ 9 _! spectrum ord]4 ,complex ,col\rs4--,we h demon/rat$ t s+le /&>d glasses develop ! ?ree ,dom9ant col\rs1 ,r$1 ,yell[1 & ,blue1 & t pairs ( equal /&>d glasses develop ! ?ree ,subord9ate col\rs1 ,orange1 ,gre51 & ,violet4 ,9 ord] to produce complex col\rs two /&>d glasses ( unequal value mu/ be us$4 ,! degree ( inequality does n alt] ! spectroscopic names ( complex col\rs1 v>iation 9 proportions be+ only a /atem5t ( degree4 ,complex ,"n4 ,high value4 ,l[]4 ,to develop a ,r$-,orange ins]t a ,r$ & ,yell[4 ,yell[-,orange ,yell[ & ,r$4 ,yell[-,gre5 ,yell[ & ,blue4 ,blue-,gre5 ,blue & ,yell[4 ,blue-,violet ,blue & ,r$4 ,r$-,violet ,r$ & ,blue4 ,a ref]5ce to ! circles1 #g1 #h1 & #i1 on ! c>ds suppli$ ) ! app>atus w %[ t all complex col\rs are memb]s ( ! same triad gr\p1 & exp]im5ts h %[n t ! six comb9ations above are ! only ones di/+ui%able 9 ,nature1 subject1 h[ev]1 to unlimit$ v>iations 9 brightness or dullness4 ,x rema9s to be %[n h[ ^! v>iations are effect$4 ,v>iations 9 brightness are produc$ by ins]t+ ) ! two glasses =m+ a complex col\r ! ?ird spectrum col\r1 always be>+ 9 m9d t x mu/ be less 9 value ?an ei!r ( ! o!r two4 ,! addition ( ! ?ird col\r has a dull+ or sadd5+ effect1 ! degree ( :i* is det]m9$ by ! num]ical value ( ! ?ird col\r4 ,! col\r produc$ by ! addition ( ! ?ird col\r may be t]m$ a sadd5$ or d+y col\r1 ! appe>ance be+ t ( a bright] col\r se5 9 %ad[4 ,review+ ! =ego+1 x is demon/rat$ t prim>y or dom9ant col\rs are transmitt$ by a s+le col\r$ /&>d glass2 ! second>y or subord9ate col\rs are transmitt$ by two equal /&>d glasses ( diff]5t col\rs2 ! complex col\rs by two unequal /&>d glasses ( diff]5t col\rs4 ,sadd5$ pure col\rs are develop$ ei!r by "o col\r$ /&>d glass comb9$ ) two equal /&>d glasses ( diff]5t col\rs & less] value or by two equal /&>d glasses ( diff]5t col\rs & a ?ird ( less] value4 ,sadd5$ complex col\rs by ?ree unequal /&>d glasses ( diff]5t col\rs4 ,greys1 :i* are /eps t[>ds blackness1 are produc$ by ?ree equal /&>d glasses ( diff]5t col\rs4 ,x is well kn[n t ,col\r ,bl9dness is a defect 9 ! vision (t5 involv+ ! confusion ( su* utt]ly di/9ct col\r s5sations z ,r$ & ,gre51 ,orange & ,violet1 & _m o!rs z widely diff]5t4 ,9 ! cases ( ,r$ & ,gre5 ! confusions are specially disa/r\s %\ld ! subject be a railwayman or a sailor4 ,x is n1 h[ev]1 s well kn[n t _m cases ( s-call$ ,col\r ,bl9dness are 9 reality cases ( ,col\r ,ignorance1 & ! capacity = di/+ui%+ betwe5 col\rs & %ades is (t5 lat5t1 & only wait+ to be develop$ by ,education4 ,:5 a *ild p]si/5tly misnames col\rs aft] hav+ receiv$ an am\nt ( in/ruction suffici5t to remove col\r ignorance 9 a normal case1 ! errors are probably due to "s =m ( col\r bl9dness4 ,su* cases %\ld be regi/]$ = fur!r exam9ation1 tak+ note ( ! miscall$ col\rs4 ,x w\ld be an additional precaution to *ange ! position ( ! col\rs 9 ! w9d[s ( ! app>atus1 9 ord] to prev5t ! association ( col\rs ) _! positions z fir/ giv5 9 ! in/ructions4 ,note4--,! pa9ts :i* mo/ ne>ly correspond to ! col\r /&>ds 9 ! ,col\r ,educator are tabulat$ bel[1 ! ?ird column conta9+ _! measur$ col\r proportions :5 !y are wa%$ ?ickly on :ite pap] 7,:atman's74 ---------------------------------------- ------------------------------------ ,col\r ,composition 9 ,/&>d ,units4 ,spectrum ,arti/s' ---------------------------------------- -- ,names ,names4 ,r$4 ,orange4,yell[4 ,gre54 ,blue4 ,violet4 ---------------------------------------- ------------------------------- ,dom9ants3 ,r$ ,crimson ,lake #ahj #jd ---- ---- ---- ---- ,yell[ ,lemon ,yell[ ---- ---- #ff ---- ---- ---- ,blue ,cobalt ---- ---- ---- ---- #ij ---- ,subord9ates3 ,orange ,*rome ,orange ---- #gb #af ---- ---- ---- ,gre5 ,em]ald ,gre5 ---- ---- #jdj #ed ---- ---- ,violet ,mauve #cc ---- ---- ---- ---- #hb ---------------------------------------- ------------------------------- ,9 mix+ two dom9ant col\rs 7arti/s' prim>ies7 to develop subord9ates 7arti/s' second>ies71 _! relative col\r dep? mu/ be tak5 into acc\nt2 = in/ance1 ,crimson ,lake has a natural col\r dep? ne>ly ?ree times t ( ,lemon ,yell[2 !re=e1 9 ord] to develop a normal ,orange ne>ly ?ree times ! quantity ( ,yell[ mu/ be us$1 presum+ t !y 7 orig9ally gr\nd to an equal degree ( f95ess4 ,x is desirable t a record ( ! *ildr5's own pa9t+ %\ld be pres]v$1 ) a view to discrim9at+ betwe5 errors aris+ f ,col\r ,bl9dness & ,col\r ,ignorance1 ! =m] p]petuat+ itself1 & ! latt] naturally rem$y+ itself4 ,= ?is purpose pa9t+ books conta9+ sets ( diagrams correspond+ to ! figures 9 ! =ego+ pamphlet c be suppli$4 ,app5dix ,,ii ,,! ,,possibilities ,,( ,a ,,/&>d ,,light ,,& ,,col\r ,,unit4#e #e ,repr9t$ f ! ,j\rnal ( ! ,society ( ,dy]s & ,col\ri/s1 ,m>*1 #aiac4 ,no4 #c1 vol4 xxix4 ,! pa/ attempts to /&>dize light & col\r are ma9ly limit$ to ^? radiant en]gies :i* excite light & col\r s5sations "u diffus$ daylight conditions1 because 9 direct sunlight1 & 9 mo/ artificial lights1 !re are o!r col\r en]gies1 :i*1 unless suffici5tly modifi$ by diffusion1 di/urb ! col\r read+s4 ,!re are also lat5t col\r en]gies1 :i* only become di/+ui%able by special means4 ,!y d n1 h[ev]1 appe> to influ5ce diffus$ daylight col\r "w4 ,! def9ition ( a normal vision is "o :i* agrees ) a majority ( o!rs4 ,?is def9ition has prov$ satisfactory up to ! pres5t1 z ! normals are _m & ! col\r bl9d few4 ,light ,int5sities4--,!re are two me?ods ( det]m9+ light int5sities by means ( a grad$ scale ( light absorb5ts4 ,fir/4 ,by total absorption ( ! light1 :5 ! int5sity is directly repres5t$ by ! unit value ( ! absorb5ts requir$4 ,?is me?od is applicable = l[ lights1 int]nal surfaces1 su* z a desk1 etc41 :]e a /&>d light is n available = comp>ison4 ,second4 ,by ! r$uction ( a /&>d light by absorption until x equals ! light ( ! object4 ,9 ?is case ! /&>d mu/ be orig9ally bright] ?an ! object4 ,con/ants4--,! fir/ requirem5t 9 e/abli%+ a scale ( light & col\r units is a means ( co-relat+ visual s5sations to a scale ( physical col\r con/ants1 9 ord] to secure a p[] ( record & recov]y4 ,!re is no natural scale available = quantitative col\r "w1 b artificial scales c be con/ruct$1 & made con/ants by co-relation at diff]5t po9ts ) physical col\r con/ants1 & by cross-*eck+ ! int]vals betwe5 ^!4 ,! scales us$ 9 ! 8t9tomet]0 consi/ ( r$1 yell[ & blue glass1 s grad$ 9 equival5ts t comb9ations ( equal units transmit col\rless light4 ,full details ( ^! h already be5 plac$ be=e ! ,society 7see ?is ,j\r41 #ahhg1 p4 #ahf1 & #aijh1 p4 #cf74 ,scale ( ,lum9\s ,int5sities4 ,! ,light ,unit4--,! natural t]m9als 9 a scale ( lum9\s int5sities are black & :ite1 & ! fir/ "q :i* arises is :at is black1 & :at is :ite8 z :5 us$ 9 a popul> s5se ea* t]m cov]s a wide range ( diff]5ces4 ,9 ! au?or's s5se ! t]m black means total abs5ce ( light1 & ! t]m :ite means a diffus$ daylight ( giv5 int5sity1 z reflect$ f a lime sulphate surface4 ,9 ?is s5se black & :ite are ! t]m9als ( a scale ( light int5sities2 ! scale is divid$ into units & fractions ( units4 ,! unit itself is physiological1 & is n 9 progressive accord ) ! ma!matical light unit bas$ on ! inv]se squ>es ( di/ance4 ,! ,black ,unit4--,ideal black is practically obta9$ "u daylight conditions by view+ a hole 9 a box ) black5$ int]ior1 s arrang$ t no ent]+ light c be reflect$ back to ! vision4 ,! box us$ = ?is purpose is illu/rat$ 9 ,fig4 #c1 & has "o surface cov]$ ) /&>d :ite = ! purpose ( easy comp>ison ) ! pigm5ts4 ,! /&>d black ap]ture 7#a7 is 9 ! middle4 ,! pigm5t>y blacks 7#b to #aj7 are arrang$ ov] ?is1 & ! pigm5t>y :ites & greys 7#aa to #bj7 und]nea?1 ea* be+ numb]$ 9 accord ) its int5sity z tabulat$4 ,illu/ration3 ,fig4 #c4 ,! degrees ( blackness are ! numb] ( absorptive units requir$ to r$uce ! /&>d :ite to equal ! pigm5ts 9 ea* case4 ,light ,absorb$ by ,v>i\s ,pigm5ts4 ---------------------------------------- --------- ,no4 ,absorb$,unabsorb$,initial ,light4 ,light4 ,light4 ---------------------------------------- --------- #a ,black ,hole 9 ,box #cf -- #cf #b ,optical ,black #bj #af #cf #c ,lamp ,black #ag #ai #cf #d ,vegetable ,black ,a #ag #ai #cf #e ,b #ad #bb #cf #f ,c #ae #ba #cf #g ,indian ,ink on ,pap] #ad #bb #cf #h ,solid #ab #bd #cf #i ,boot ,black #aa #be #cf #aj ,black ,lead #i #bg #cf ---------------------------------------- --------- ,?is gives a work+ scale ( col\rless light int5sities1 ! t]m9als be+ black & :ite1 ) a range ( #cf units4 ,! ,/&>d ,:ite4--,:ite is ! natural t]m9al ( ! lum9\s end ( ! scale1 & x is necess>y to select a physical objective :ite z a con/ant4 ,pure precipitat$ lime sulphate has be5 adopt$1 & dep>tures f ! light int5sity ( ?is are record$ 9 units ( less5$ light int5sity ?r\gh\t ! scale1 compris+ all degrees ( col\rless :ites1 greys1 & blacks4 ,/rictly speak+1 :ite is a qualitative t]m only1 until ! degree ( v>iation f ! z]o ( ! scale has be5 e/abli%$4 ,! measur$ v>iation !n takes its position 9 ! scale ( lum9\s int5sities accord+ to its num]ical unit value4 ,light ,absorb$ by ,v>i\s ,:ite & ,grey ,pigm5ts4 ---------------------------------------- - ,no4 ,pigm5ts4 ,absorb$,reflect$,initial ,light4 ,light4 ,light4 ---------------------------------------- - #aa ,grey ,pa9t ,e #fj #cjj #cf #ab ,d #ej #caj #cf #ac ,c #dj #cbj #cf #ad ,b #bj #cdj #cf #ae ,:ite ,pa9t ,a #jg #cec #cf #af ,:ite ,pap] ,d #jc #ceg #cf #ag ,c #jb #ceh #cf #ah ,b #jbe #cege #cf #ai ,a #jae #cehe #cf #bj ,*9ese ,:ite #jjjf #ceiid #cf ---------------------------------------- - ,z ! scale is diff]5tiat$ into hundr$?s ( a unit1 !re c be #ajj v>iations ( :ite pigm5ts 9 a s+le unit1 ea* q easily di/+ui%able f ! o!rs4 ,any def9ite mixture ( black & :ite f9ds a position on ! diagonal ( a *>t ^: co-ord9ates are ! black & :ite scales2 = example1 ! #bj measur$ pigm5ts are *>t$ on ,figs4 #d & #e1 ! latt] be+ on an enl>g$ scale1 z ! :ites w\ld be too cr[d$ to be not$ on ,fig4 #d4 ,illu/ration3 ,fig4 #d4 ,! m]g+ ( :ite into grey1 & ( grey into black is gradual1 hav+ no /rict l9es ( dem>cation4 ,an example ( ?is me?od ( det]m9+ light int5sities is illu/rat$ 9 ,fig4 #f by ! light int5sities at :i* diff]5t objects are disc]nible4 ,! po9ts ( mo/ int]e/ are1 t col\r is indi/+ui%able z su* 9 lights bel[ #ae units int5sity2 & t ord9>y "w1 su* z read+ a newspap]1 requires = com=t a m9imum ( #bh units4 ,! ,col\r ,unit4--,! col\r unit is physiological1 & its dim5sions are det]m9$ by ! dim5sions ( ! col\rless light f :i* x is d]iv$4 ,?is d$uction is bas$ on ! exp]im5tal fact t col\rless light is a mixture ( ! six col\r rays--r$1 orange1 yell[1 gre51 blue1 & violet--9 equal proportion1 z illu/rat$ 9 ,fig4 #g1 %[+ t a :ite light ( #bj units light int5sity is made up to ! six col\r rays1 ea* ( #bj units col\r int5sity4 ,?is is demon/rat$ by ! fact t any proportion ( any col\r c be develop$ at w by means ( ! glass /&>d scales already m5tion$2 x foll[s t ! smalle/ di/urbance ( equival5ce betwe5 ! compos+ rays results 9 ! developm5t ( col\r4 ,illu/ration3 ,fig4 #e4 ,! above rem>ks apply to bo? simple & complex col\rs1 & ! complex col\rs are always di*romes1 be+ gov]n$ by ano!r physiological fact1 :i* is3 ,t ! vision is unable to simultane\sly di/+ui% m ?an two col\rs 9 ! same beam ( light4 ,! ord] ( _! association is def9ite1 & may be describ$ by say+ t ! comb9$ two are always adjac5t 9 _! spectrum ord]1 r$ & violet be+ consid]$ adjac5t = ?is purpose4 ,x foll[s t all complex col\rs are b9>ies1 & ! only possible comb9ations are z foll[s3-- ,r$ ) ,orange4 ,orange ,yell[4 ,yell[ ,gre54 ,gre5 ,blue4 ,blue ,violet4 ,violet ,r$4 ,illu/ration3 ,fig4 #f4 ,9 ! au?or's col\r nom5clature1 a mono*rome is qualitatively describ$ by a s+le t]m1 & a complex col\r by a comb9ation ( two s+le t]ms4 ,= a quantitative description1 x is only necess>y to add ! measur$ unit value to ea* t]m4 ,:5 !re is excess ( brightness1 or a sadd5+ factor1 ^! also mu/ be quantitatively e/imat$4 ,! col\rs develop$ by means ( ^! scales are gov]n$ by ! same law ( selective absorption :i* gov]ns ! developm5t ( natural col\rs1 any ( :i* c be mat*$ & reproduc$ by means ( _! e/abli%$ ray proportions4 ,illu/ration3 ,fig4 #g4 ,! gov]n+ law is simple1 & may be /at$ by say+ t ! col\r develop$ is always complem5t>y to ! col\r absorb$1 n 9 ! g5]ally accept$ s5se t _! mixture necess>ily makes :ite light1 b 9 ! s5se t !y are opposite 9 ! cycle ( daylight col\rs4 ,! dim5sions ( ! unit are necess>ily arbitr>y1 x 0 orig9ally select$ z be+ a conv5i5t dep? = di/+ui%+ diff]5ces1 ! scale 0 !n con/ruct$ by equal additions & sub-divisions2 ! two ess5tials ( a sci5tific scale be+ compli$ )1 9 t ! divisions 7 equal & ! unit recov]able4 ,! p[] ( recov]y lies 9 ! fact t diff]5t p>ts ( ! scale are co-relat$ to physical col\r con/ants1 :i* c be prep>$ 9 any laboratory4 ,illu/ration3 ,,plate ,,viii ,,absorption ,,curves ,,( ,,six ,,dyes4 ,to face page #gf4 ,lovibond1 ,col\r ,!ories4 ,specific ,col\r4--,! relation%ip ( col\r increase to int5sity increase 9 sub/ances has hi!rto be5 some:at obscure4 ,x has be5 sometimes consid]$ t !y 7 9 direct proportion1 b 9 ! abs5ce ( a means ( record+ col\r s5sations1 no def9ite results 7 obta9able4 ,illu/ration3 ,fig4 #h4 ,suffici5t in=mation is n[ available to w>rant ! =mulation ( ! foll[+ law3 8,t e sub/ance has its own rate ( col\r developm5t = regul>ly increas+ int5sities1 :i*1 :5 once e/abli%$1 becomes a con/ant = id5tify+ simil> sub/ances 9 future40 ,?is is ! mean+ ( specific col\r1 & :5 a s]ies ( measurem5ts at regul>ly increas+ d5sities ( a giv5 sub/ance h be5 made1 ! specific col\r rate ( t sub/ance is e/abli%$4 ,?is c be *>t$ 9 curves & us$ z a basis = e/imat+ quantities1 prop]ties1 *anges ( condition1 diff]5ces 9 value1 detect+ adult]ation1 etc4 ,applications4--,! au?or has p]mission to use ! names ( sev]al g5tlem5 :o h us$ ! t9tometrical scales = v>i\s purposes4 ,sir ,ar?ur ,h4 ,*ur*1 ,f4,r4,s41 has employ$ ! t9tometrical /&>ds = ! purpose ( regi/]+ ! col\rs ( c]ta9 wild fl[]s4 ,sir ,bov]ton ,r$wood has us$ ! scales & sy/em = petroleum inve/igations4 ,at 8 in/ance ! specific col\r rate ( petroleum 0 e/abli%$1 & ! sev]al compos+ col\rs plott$ 9 curves1 z 9 ,fig4 #h1 :]e ! ord9ates repres5t ! scale ( units irrespective ( col\r1 & ! absciss ! scale ( /rata ?icknesses4 ,! measurem5ts 7 made at two-in* int]vals1 & ! f\r p]p5dicul> l9es are at ! col\r po9ts select$ = valu+ ! f\r di/+ui%+ m>ks1 te*nically kn[n z 8,wat] ,:ite10 8,sup]f9e10 8,prime10 & 8,/&>d40 ,int]m$iate qualities f9d _! position 9 ! scale ( curves accord+ to _! measur$ col\r values4 ,?is me?od ( /&>diz+ comm]cial values has also be5 adopt$ by ! ,int]national ,tann]s' ,association1 ! ,int]-,/ates ,cotton ,se$ ,oil ,association1 & o!r oil indu/ries4 ,also = scale1 solid fats1 & su* sub/ances z c be easily melt$ & measur$ by transmitt$ light4 ,v>y+ ,effects ( ,diff]5t ,lights4 ,pa?ological ,applications4--,! law ( specific col\r developm5t 0 made use ( by ,dr4 ,george ,oliv] 9 det]m9+ ! degrees ( hmoglob9 9 ! blood4 ,! me?od is fully expla9$ 9 8 ,croonian ,lecture be=e ! ,royal ,college ( ,physicians ( ,london1 ,july #aa1 #ahif4 ,detection ( ,=g]ies4--,! sy/em & app>atus is us$ by ,pr(essor ,a4 ,s4 ,osborne1 ,exam9] ( ,que/ion$ ,docum5ts1 ,new ,york ,city1 = det]m9+ ! v>iety ( ink1 ! age ( ! writ+1 & ! detection ( =g]ies4 ,a full description ( ! process w be f\nd 9 8 "w entitl$ ,que/ion$ ,docum5ts1 publi%$ by ! ,lawy]s' ,co-op]ative ,society1 ,ro*e/]1 ,n4,y4 ,illu/ration3 ,,plate ,,ix ,,six ,,anil9e ,,dyes4 ,,curves ,,illu/rat+ ,,! ,,rate ,,( ,,fad+ ,,by ,,exposure ,,to ,,light4 ,to face page #gh4 ,lovibond1 ,col\r ,!ories4 ,! application to *emical analysis is too well kn[n to require enl>gem5t "h4 ,illu/ration3 ,fig4 #i4 ,dyes4--,z an example ( ! use ( ! sy/em 9 ! valuation ( dyes1 ,fig4 #i illu/rates ! specific col\r curves ( f\r samples ( ,me?yl5e ,blue4 ,no4 #a 0 pric$ at #es4 #i;d4 & ,no4 #b at #es4 p] lb41 ,nos4 #c & #d 7 n pric$1 ! solutions 7 measur$ 9 p]c5tages f #jjja to #jjdh 9 di/ill$ wat]4 ,to f9d ! co/ p] unit ( col\r 9 ! pric$ samples is only a "q ( simple ari?metic1 :i* furni%es data = ! valuation ( ! unpric$ samples4 ,! yield 9 ! dye vat may n be 9 direct relation to ! solutions 9 wat]1 ! e/abli%m5t ( ?is is a "q = ! exp]t1 & pres5ts no app>5t difficulty4 ,! use ( ! s*eme 9 record+ ! degree ( fad+ ( dyes has be5 previ\sly dealt ) 9 ! ,j\rnal 7q4v41 #aijh1 p4 #cf74 ,limitations & ,precautions4--,x has be5 %[n t we h analytical control1 )9 c]ta9 limits1 ( light & col\r "u daylight conditions4 ,! g5]al limits = col\rless light range f total d>kness to #bh units1 :5 ! unabsorbable r$ ray comes into evid5ce4 ,= col\r1 ! g5]al limits range f #bh to #ah units1 betwe5 #ah & #ae all col\rs become indi/9ct1 b at v>y+ rates1 bel[ #ae1 col\r is n di/+ui%able4 ,! pr9cipal di/urb+ conditions 9 mak+ obs]vations are want ( col\r education & insuffici5t diffusion4 ,9 ! case ( ! latt]1 ! fir/ evid5ce is ! di/urbance ( con/ancy by ! p5etrat+ r$ ray4 ,a p>tial rem$y is to int]pose a :ite diffusion scre51 su* z tissue pap]4 ,"t ( ,obs]vation4--,?is %\ld n exce$ five consecutive seconds1 z ! ke5ness ( p]ception decreases by "t1 b v>ies = diff]5t col\rs4 ,angle ( ,incid5ce4--,sixty degrees is safe = mo/ solids1 b = bright or poli%$ surfaces1 su* z v>ni%es1 poli%$ metals1 etc41 ! angle mu/ be less5$ z ! degree ( smoo?ness increases4 ,= v r\gh surfaces1 su* z loosely wov5 /uffs1 etc41 c>e mu/ be tak5 t ! lay ( ! fibre is uni=m4 ,di/ance f ! ,object4--,t5 in*es has be5 adopt$ = g5]al "w1 b c]ta9 visions require m or less z _! focus v>ies f normal4 ,illu/ration3 ,,plate ,x ,,comp>ison ,,curves ,,( ,,heal?y ,,& ,,diseas$ ,,blood4 ,to face page #hj4 ,lovibond1 ,col\r ,!ories4 ,unabsorbable ,col\rs4--,9 addition to ! daylight col\rs already dealt )1 !re are1 9 direct lights1 col\rs :i* d n obey ! laws ( absorption gov]n+ ^? ( diffus$ daylight4 ,! "w already done on ^! unabsorbable rays has only be5 incid5tal1 :]e !y happ5$ to int]f]e ) ! /&>dization ( diffus$ daylight col\rs4 ,! s5sations excit$ are r$ & violet4 ,!y bl5d1 produc+ r$-violet mixtures1 b 9 unequal proportions1 ! r$ be+ dom9ant4 ,! r$ is develop$ 9 int5se lights by con/ant int]ception ( neutral t9t absorb5ts4 ,9 ! case ( a #d-volt inc&esc5t light1 ! fir/ absorption simply r$uces ! light int5sity )\t develop+ col\r2 ! light is col\rless up to #ad units4 ,at #af units ! light beg9s to assume a r$di% hue1 :i* rapidly becomes a brilliant int5se r$ by fur!r int]ceptions ( neutral t9t absorb5ts4 ,violet is develop$ by con/ant absorption by blue /&>ds1 :i* gr[s 9 int5sity by successive additions up to ab\t #abj units4 ,beyond ?is po9t ! brilliancy decreases4 ,prelim9>y exp]im5ts po9t to ?is ray z fatal to vegetation1 & presumably also to l[] =ms ( organic life4 ,!re rema9s a factor ( consid]able importance :i* has n yet receiv$ ! att5tion x des]ves1 ! physiological *anges result+ f environm5t4 ,?is aspect ( ! "q has come "u ! notice ( ! au?or by measur+ ! vision ( exp]ts :o excell$ 9 giv5 hues4 ,x 0 g5]ally f\nd t _! vision 0 s5sitive to a small increm5t ( _! p>ticul> col\r 9 h>monies :]e x 0 sil5t to a normal vision4 ,9 seek+ an explanation ( ?is ph5om5on !re are at lea/ ?ree possible l9es = work+3 ,fir/4 ,is ! vision naturally m s5sitive to t p>ticul> en]gy8 ,second4 ,is x by c>eful education8 ,?ird4 ,is x an unconsci\s adaptation to surr\nd+s1 su* z o!r organs und]go "u *anges ( environm5t8 ,illu/ration3 ,,plate ,,xi ,,specific ,,col\r ,,curves ,,( ,,heal?y ,,& ,,diseas$ ,,human ,,blood ,to face page #hb4 ,lovibond1 ,col\r ,!ories4 ,app5dix ,,iii ,,! ,,application ,,( ,,! ,,natural ,,law ,,( ,,specific ,,col\r ,,rate ,,by ,,dr4 ,,dudley ,,corbett ,,to ,,! ,,exact ,,measurem5t ,,( ,x-,,ray ,,dosage4 ,dr4 ,dudley ,corbett4 ,! gradations 9 ! t9t giv5 by ! ,sab\raud-,noir pa/ille :5 expos$ to ,x-rays are s f9e1 especially 9 t region ( ! col\r scale :]e lies ! ery!ma dose1 t _m h felt ! want ( a m accurate means ( read+ ^! t9ts1 z well z a s]ies ( reliable /&>ds = comp>ison4 ,hi!rto ! only me?ods at all g5]ally us$ h be5 ,hampson's radiomet] & ,bordi]'s radio-*ronomet]1 ! =m] 9 ?is c\ntry1 & ! latt] on ! ,cont95t4 ,hampson's in/rum5t has two disadvantages3 x c only be us$ ) electric light1 & ! /&>ds are made ( t9t$ pap] liable to get soil$1 & to v>y slightly ) ! *anges 9 ! pigm5t employ$4 ,its advantage is t x may be us$ z a slid+ scale1 ?us economis+ ! pa/illes4 ,"s p]sons1 h[ev]1 h consid]able difficulty 9 read+ ! t9ts1 ! scale ris+ only by gradations ( #a_/d ,b4 ,9 ! con/ruction ( any su* in/rum5t1 ! really important po9t is to obta9 a reliable /&>d = ,t9t ,b--i4e41 ! normal epilation dose4 ,! t9ts on ! ,sab\raud c>d itself are n always id5tical1 "s repres5t+ a dose :i* w only j epilate1 o!rs an almo/ dang]\s dose = unfilt]$ rays4 ,! ,t9t ,b1 :i* is ! /&>d1 all[s a m>g9 ( error ( #bj p] c5t4 on ei!r side4 ,9 o!r words1 #d_/e ,b w almo/ always epilate1 :ile #a-a_/e ,b is ne>ly ! limit ( safety4 ,?is obs]vation is 9 accordance ) ! exp]i5ce ( o!r work]s on ?is subject4 ,9 my in/rum5t ,t9t ,b has be5 obta9$ by measur+ ! pa/ille ) ,lovibond's t9tomet] imm$iately aft] exposure to ! ,x-rays4 ,! pa/ille 0 turn$ to a t9t correspond+ to an epilation dose :i* 0 kn[n to be safe1 z prov$ by cl9ical results4 ,?is t9t 0 measur$ directly bo? by daylight & by artificial light f an #h-;c&le p[] c>bon filam5t lamp ) fro/$ glass %ade4 ,i am indebt$ to ,mr4 ,dean = sugge/+ ! use ( ,lovibond's in/rum5t = ?is purpose4 ,! me?ods employ$ 9 ! exp]im5tal "w h be5 describ$ 9 ! ,briti% ,j\rnal ( ,d]matology = ,augu/1 #aiac4 ,by us+ a v con/ant focus tube & av]ag+ a l>ge numb] ( read+s & correlat+ ! results ) ^? obta9$ 9 cl9ical practice1 we 7 able to con/ruct ! curves indicat+ ! col\r develop$ by ! pa/ille4 ,9 ^! curves1 %[n 9 ,fig4 #aj1 ! ord9ates are ! ,lovibond col\r units1 ! abscissa ! "t dur+ :i* ! curr5t 0 actually pass+4 ,:5 us+ an int]rupt] work+ at a con/ant spe$1 ! actual "t 0 tak51 o!rwise ! numb] ( curr5t int]ruptions z measur$ by a dipp] ta*ymet] 0 us$4 ,z 0 to be expect$1 ! daylight & electric light curves 7 q diff]5t4 ,9 ea* case ! /&>d yell[ glasses employ$ 7 kept con/ant ?r\gh\t ! curve1 t = daylight be+ #ae units1 t = electric light #ac units4 ,:5 ^! 7 comb9$ ) blue & r$ glasses 9 v>y+ units & fractions ( a unit1 !y gave a col\r range :i* mat*$ ! pa/ille exactly 9 ! *anges x und]goes f ! unexpos$ condition to ! #b ,b ,t9t4 ,! curves are plott$ 9 accordance ) ,mr4 ,lovibond's practice--t is1 n z a direct repres5tation ( ! /&>d glasses us$1 b z %[+ ! col\r s5sation receiv$ by ! eye4 ,illu/ration3 ,fig4 #aj4 ,fir/1 z to ! daylight curve3 ,9 ord] to mat* ! unexpos$ pa/ille we int]pose betwe5 ! pa/ille & ! obs]v]'s eye a yell[ & a blue glass1 plus a c]ta9 am\nt ( neutral t9t 7compos$ ( ?ree equal col\r units74 ,?us ! col\r s5sation receiv$ is a yell[ gre51 toge!r ) a c]ta9 am\nt ( :ite light4 ,z ! pa/ille d>k5s "u irradiation1 bo? ! gre5 & ! :ite light disappe>1 until at a po9t j bel[ ! #a_/b ,b dose1 !re is no o!r col\r pres5t b yell[4 ,aft] ?is r$ glasses are requir$--i4e41 ! col\r s5sation is a yell[ orange1 :i* gradually deep5s ow+ to an increase 9 ! proportion ( r$4 ,! yell[ curve ?us rises till j bel[ ! #a_/b ,b po9t1 & !n falls z ! orange increases4 ,next1 z to ! electric light curve4 ,! unexpos$ pa/ille has b a trace ( gre51 :i* is soon lo/4 ,! orange beg9s mu* e>li] ?an 9 daylight1 & ?us at ,t9t ,b has rea*$ a high] po9t ?an 9 daylight4 ,f ?is po9t ! orange & yell[ p>ts ( bo? curves run practically p>allel ) "o ano!r up to #b ,b4 ,beyond #b ,b ! read+s become m difficult4 ,i h n det]m9$ ! po9t :5 no m col\r develops1 z x has no great practical value1 ?\gh x might well be ( int]e/ f a physico-*emical /&po9t4 ,9 my radiomet] ! /&>ds are compos$ ( ! ,lovibond /&>d glasses 9 comb9ation4 ,! app>atus itself consi/s ( an optical in/rum5t or view+ box4 ,?is is divid$ by a c5tral p>tition1 s t on look+ ?r\gh ! eyepiece "o sees a :ite backgr\nd ?r\gh two small circul> ap]tures4 ,on "o side1 level ) ! backgr\nd1 is a fitt+ to take ! pa/ille 9 its hold]4 ,on ! o!r side is a groove 9 ! in/rum5t itself = ! ins]tion ( ! /&>d glasses4 ,a simil> groove is fitt$ on ! pa/ille side ( ! in/rum5t to take neutral t9ts if requir$4 ,! col\r ( ! pa/ille z se5 by reflect$ light c ?us be comp>$ ) t obta9$ by transmitt$ light ?r\gh ! /&>d glasses se5 aga9/ ! :ite backgr\nd4 ,a diff]5ce ( #a_/e ,b or #a ,h is q easily p]ceivable4 ,x is usually ( no great importance to obta9 extremely accurate measurem5t ( ! small] fractions bel[ #a_/c ,b4 ,:]e ?is is necess>y1 neutral t9ts mu/ be us$ :5 work+ ) daylight4 ,) electric light ^! are unnecess>y4 ,:5 requir$ ! neutral t9ts are int]pos$ betwe5 ! pa/ille & ! eye to absorb ! :ite light reflect$ f ! pa/ille4 ,! neutral glasses requir$ are #ae = ! unexpos$ pa/ille1 #jf = #a_/d ,b1 & #jb = #a_/c ,b4 ,^! values are subject to slight v>iations due to *anges 9 ! v>ni% ( ! pa/ille emulsion4 ,! difficulty c always be avoid$ by us+ electric light1 :]e a trace ( neutral t9t is ne$$ only :5 mat*+ ! unexpos$ pa/ille--an unimportant po9t4 ,me?od ( ,use4--,! *oice ( daylight or artificial light is a p]sonal matt]1 b "o %\ld practise read+ ! scale ) bo?4 ,! use ( ! in/rum5t %[s t ! pa/ille fades v ne>ly z quickly "u electric light z x does "u daylight4 ,! foll[+ precautions %\ld be obs]v$3 ,9 daylight "w 9 a good :ite light1 avoid %ad[s & yell[ light ( any k9d4 ,) electric light use an #h-;c&le p[] c>bon-filam5t lamp ) fro/$ glass & a suitable :ite %ade s arrang$ t ! pa/ille is #h in*es f ! lamp4 ,no o!r light %\ld be all[$ to rea* ! pa/ille dur+ exam9ation4 ,a l[ p[] metal-filam5t lamp may be us$1 b great] accuracy w be obta9$ ) a c>bon-filam5t lamp :i* 0 us$ = ! exp]im5tal "w4 ,! lamp %\ld be disc>d$ z soon z ! light becomes yell[ f prolong$ use4 ,:e!r 9 daylight or electric light1 ! exam9ation mu/ be rapid to avoid ! fad+ ( ! pa/ille4 ,:5 x is desir$ to give an accurate #a ,b dose1 x is bett] to put up ! #d_/e ,b /&>d fir/4 ,x is !n easy to calculate h[ mu* m exposure is requir$ = ! extra #a_/e ,b4 ,x is important to adju/ ! pa/ille c>efully s t none ( ! unirradiat$ gre5 portion is visible ?r\gh ! small ap]ture1 z ?is w upset ! read+4 ,9 v accurate dosage new pa/illes %\ld be us$1 z a blea*$ pa/ille nev] returns exactly to its orig9al t9t4 ,:5 su* a blea*$ pa/ille is irradiat$ ! col\r *anges />t a little f>!r d[n ! curve1 & ?us ! t9t = a giv5 dose mu/ be tak5 a little above ! normal t9t4 ,?is increase is v slight1 b is nev]!less q appreciable1 & may am\nt to z mu* z #e & #aj p] c5t4 ,ev5 !n ! m>g9 = error is ample 9 ! neighb\rhood ( ! ,b t9t1 & if a pa/ille is n us$ m ?an ?ree times1 & is well blea*$ 9 daylight aft] ea* exposure1 no s]i\s error is likely to occur4 ,a /&>d :ite backgr\nd %\ld always be us$1 & disc>d$ = a new "o :5 x gets dirty4 ,! col\r /&>ds usually provid$ are ^? 9 common use--namely1 #a_/d1 #a_/c1 #a_/b1 #d_/e1 #a1 #a'1 & #b ,b1 b x is q easy to make up /&>ds = any po9t on ! curve4 ,! symbol 8,b10 z ! ery!ma or epilation dose1 has be5 reta9$1 z x 0 ?\ght inadvisable to add to ! numb] ( su* symbols already exi/+4 ,to sum up3 #a4 ,! exp]im5tal "w has det]m9$ ! exact col\r *anges occurr+ 9 ! ,sab\raud pa/ille :5 expos$ to ,x-rays4 #b4 ,^! exp]im5ts h e/abli%$ a p]man5t /&>d = ,t9t ,b1 :i* mat*es ! pa/ille exactly1 does n fade1 is easily kept clean4 ,^! col\r$ glasses c be readily & accurately reproduc$1 z !y are /&>diz$ spectroscopically by a firm :o specialise 9 su* "w4 ,! /&>d w !re=e rema9 con/ant s long z ! ,sab\raud emulsion rema9s unalt]$4 #c4 ,glasses may be prep>$ ( ! correct t9t = any fraction or multiple ( ?is dose up to #b ,b or #aj ,h4 #d4 ,ei!r daylight or electric light c be us$4 #e4 ,! optical in/rum5t itself1 by cutt+ (f extrane\s light1 greatly assi/s ! col\r comp>isons1 s t ! practical error ne$ nev] exce$ #aj p] c5t4 ,,index ,abnormal light1 #ac ,analysis ( :ite light1 #aa1 #ac ,arbitr>y scales1 #i ,arti/s & sci5ti/s1 #a1 #b ,beam ( :ite light1 #g1 #aa ,black units1 #af1 #bc ,black1 ideal1 #ae1 #aa ,blood curves1 #cc ,code ( laws1 #g ,col\r *>ts1 #ca1 #ci education1 #ei equival5ce1 #aj nom5clature1 #ag1 #ba qualitative1 #ag1 #ai1 #bd quantitative1 #bd scales1 #bj1 #bi /&>dization1 #bj1 #fi !ories1 #b1 #c ,col\r$ surfaces1 #dd ,col\rs1 complex1 #ah sadd] ?an /&>ds1 #be simple1 #ag ,corbett1 ,dr4 ,dudley's1 radiomet]1 #hc ,daylight col\rs1 #bd1 #hd measurem5t1 #ad ,diffus$ light1 #aj1 #dc ,direct lights1 #df ,dull$ col\r1 #aj1 #ah-bf1 #cf ,equival5t col\r units1 #g1 #i1 #bi ,fog1 :it5ess (1 #aj ,glass /&>ds1 #bj ,human blood curves1 #hb ,laws ( col\r1 #g ,light1 #aa1 #ac1 #db1 #de-df1 #ha-hd abnormal1 #h bright] ?an /&>ds1 #ad1 #bg direct1 #df = col\r "w1 #db int5sities1 #db1 #dc :ite1 #ad ,lovibond's new col\r !ory1 #e ,mat*+ col\rs bright] ?an /&>ds1 #ah complex col\rs1 #ag ,measur+ & nam+ col\rs1 #ba ,mono*romes1 #ag1 #ai ,munro1 ,dr41 #cd ,neutral t9t1 #ah1 #bd1 #bf ,nor? light1 #ae ,pa/ !ories1 #c ,photographic en]gies1 #ec ,physical col\r con/ants1 #h ,pigm5t>y black1 #ae1 #ga ,prim>y col\rs1 #a ,prismatic spectrum col\rs1 #bi ,qualitative analysis ( col\r1 #ag1 #ai1 #bd ,quantitative analysis ( col\r1 #bd ,radiomet]1 #hc ,rate ( col\r absorption1 #h ,rays1 six col\r1 #g ,r$ ray1 #da ,scales1 arbitr>y col\r1 #i col\r$1 #aj1 #bj cross *eck+ (1 #i ,sci5ti/s & arti/s1 #a1 #b ,sea fog1 #aj ,specific col\r1 #cb ,spectrum col\rs1 #d1 #ah1 #cf ,?ree col\rs1 #aj1 #eg ,"t1 appreciation ( col\r by1 #db ,ultra violet1 #cb1 #dj ,unit1 *eck+ (1 #i ,unit1 neutral t9t1 #ah1 #bd1 #bf ,wave l5g? position1 #cg1 #ch ,:ite light1 #aa1 #ac ,butl] ,tann] ,frome & ,london ,transcrib]'s notes3 ,9 ! text v]sion1 italics are repres5t$ by und]scores1 & bold & black lett] text by equals symbols4 ,sup]scripts are repres5t$ by & subscripts by ,miss+ or incorrect punctuation has be5 repair$4 ,inconsi/5t spell+ & hyph5ation h be5 left1 ,9 ! html v]sion1 dittos h be5 replac$ by ! repeat$ text s t text aligns = easi] read+4 ,v wide tables 7,v & ,,vi & ,,vii7h be5 split to fit on portrait ori5t$ pages4 ,! foll[+ mi/akes h be5 not$3 p4 #ba4 ,ni,s,o#dg;,h#b,o1 tem4 is =matt$ inconsi/5tly4 ,left z pr9t$4 p4 #dj4 ,fraunhop] is almo/ c]ta9ly a typo = ,fraunh(]4 ,left z pr9t$4 p4 #df4 int]pretat$ *ang$ to int]pret$4 p4 #ee4 ,9 ,pap] #f ( table1 ,r$ scre51 yell[ entry1 f alignm5t & logic1 ! #f %\ld be 4#f4 ,left z pr9t$ p4 #fa conditons*ang$ to conditions4