第4章
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  Somepagesofletter-pressaretakenprintedononesideonly;andwaxed,torenderthemmoretransparent;thelettersarethencutoutandsorted。

  Tocomposeanewpagelinesareruledonasheetofwhitepaper,andthewordsareformedbyfixingtheseperatelettersintheirproperorder。

  Thepagebeingready,anegativephotographisproducedfromit,fromwhichtherequisitenumberofpositivephotogeniccopiesmaybeobtained。

  Anothermethod,whichrequirestheuseofthecamera,consistsinemployinglargeletterspaintedonrectangularpiecesofwood,coloredwhite。Thesearearrangedinlinesonatabletorboard,byslippingthemintogrooveswhichkeepthemsteadyandupright,thusformingapageonanenlargedscale。

  Itisnowplacedbeforeacamera,andareducedimageofitoftherequiredsizeisthrownuponthesensitivepaper。

  Theadjustmentsmustbekeptinvariable,sothattheconsecutivepagesmaynotvaryfromoneanotherinthesizeofthetype。

  Mr。Talbothaspatentedhisprocess,butwhatbenefitheexpectstoderivefromit,Iamatalosstodetermine。

  EnlargedcopiesofcalotypeorDaguerreotypeportraitsmaybeobtainedbythrowingmagnifiedimagesofthem,bymeansoflenses,uponcalotypepaper。

  THECHRYSOTYPE。

  AmodificationofMr。Talbot’sprocess,towhichthenameofChrysotypewasgivenbyitsdiscoverer,SirJohnHerschel,wascommunicatedinJune1843totheRoyalSociety,bythatdistinguishedphilosopher。

  Thismodificationwouldappeartounitethesimplicityofphotographywithallthedistintnessandclearnessofcalotype。

  Thispreparationisasfollows。

  Thepaperistobewashedinasolutionofammonio-citrateofiron;

  itmustthenbedried,andsubsequentlybrushedoverwithasolutionoftheferro-sesquicyanuretofpotassium。Thispaper,whendriedinaperfectlydarkroom,isreadyforuseinthesamemannerasifotherwiseprepared,theimagebeingsubsequentlybroughtoutbyanyneutralsolutionofgold。

  Suchwasthefirstdeclarationofhisdiscovery,buthehassincefoundthataneutralsolutionofsilverisequallyusefulinbringingoutthepicture。

  Photographicpicturestakenonthispaperaredistinguishedbyaclearnessofoutlineforeigntoallothermethods。

  CHAP。X。

  CYANOTYPE——ENERGIATYPE——CHROMATYPE——ANTHOTYPE——AMPHITYPE

  AND\"CRAYONDAGUERREOTYPE。\"

  Theseveralprocessesenumeratedattheheadofthischapter,arealldiscoveriesofEnglishphilosophers,withtheexceptionofthethirdandlastnamed。AnthotypewasfirstattemptedbyM。PontonaFrenchsavan,althoughitwasreservedtoMr。Hunttobringtheprocesstoitspresentstate。

  The\"CrayonDaguerreotype\"isanimprovementmadebyJ。AWhipple,Esq。,ofBostonI。CYANOTYPE;

  Socalledfromthecircumstanceofcyanogeninitscombinationswithironperformingaleadingpartintheprocess。

  ItwasdiscoveredbySirJohnHerschel。Theprocessisasimpleone,andtheresultingpicturesareblue。

  Brushthepaperoverwithasolutionoftheammonio-citrateofiron。

  Thissolutionshouldbesufficientlystrongtoresemblesherrywineincolor。

  Exposethepaperintheusualway,andpassoveritverysparinglyandevenlyawashofthecommonyellowferro-cyanateofpotass。

  Assoonastheliquidisapplied,thenegativepicturevanishes,andisreplacedbyapositiveone,ofavioletbluecolor,onagreenishyellowground,whichatacertaintimepossessesahighdegreeofsharpness,andsingularbeautyoftint。

  AcuriousprocesswasdiscoveredbySirJohnHerschel,bywhichdormantpicturesareproducedcapableofdevelopementbythebreath,orbykeepinginamoistatmosphere。

  Itisasfollows。

  Ifnitrateofsilver,specificgravity1。200beaddedtoferro-tartaricacid,specificgravity1。023,aprecipitatefalls,whichisinagreatmeasureredissolvedbyagentleheat,leavingablacksediment,which,beingclearedbysubsidence,aliquidofapaleyellowcolorisobtained,inwhichthefurtheradditionofthenitratecausesnoturbidness。

  Whenthetotalquantityofthenitratedsolutionaddedamountstoabouthalfthebulkoftheferro-tartaricacid,itisenough。

  Theliquidsoprepareddoesnotalterifkeptinthedark。

  Spreadonpaper,andexposedwettothesunshine(partlyshaded)

  forafewseconds,noimpressionseemstobemade,butbydegrees,althoughwithdrawnfromtheactionoflight,itdevelopesitselfspontaneously,andatlengthbecomesveryintense。

  Butifthepaperbethoroughlydriedinthedark,(inwhichstateitisofaverypalegreenishyellowcolor,)

  itpossessesthesingularpropertyofreceivingadormantorinvisiblepicture,toproducewhichfromthirtytosixtyseconds’

  exposuretosunshineisrequisite。Itshouldnotbeexposedtoolong,asnotonlyistheultimateeffectlessstriking,butapicturebeginstobevisiblyproduced,whichdarkensspontaneouslyafteritiswithdrawn。Butiftheexposurebediscontinuedbeforethiseffectcomeson,aninvisibleimpressionistheresult,todevelopewhichallthatisnecessaryistobreatheuponit,whenitimmediatelyappears,andveryspeedilyacquiresanextraordinaryintensityandsharpness,asifbymagic。

  Insteadofthebreath,itmaybesubjecttotheregularactionofaqueousvapor,bylayingitinablottingpaperbook,ofwhichsomeoftheouterleavesonbothsideshavebeendampened,orbyholdingoverwarmwater。

  II。ENERGIATYPE。

  UnderthistitleaprocesshasbeenbroughtforwardbyMr。Hunt。

  Itconsistsoftheapplicationofasolutionofsuccinicacidtopaper,whichissubsequentlywashedoverwithnitrateofsilver。

  Theimageisthentobetakeneitherinthecameraorotherwise,asrequired,andisbroughtoutbytheapplicationofthesulphateofironinsolution。Althoughthisprocesshasnotcomeintogeneraluse,itsexactdescriptionmaybeinterestingtothegeneralreader,andwethereforesubjoinit。

  Thesolutionwithwhichthepaperisfirstwashedistobepreparedasfollows:succinicacid,twodrachms;commonsalt,fivegrains;

  mucilageofgumarabic,halfafluiddrachm;distilledwater,onefluiddrachmandahalf。Whenthepaperisnearlydry,itistobebrushedoverwithasolutionofnitrateofsilver,containingadrachmofthesalt,toanounceofdistilledwater。

  Itisnowreadyforexposureinthecamera。Tobringoutthedormantpictureitisnecessarytowashitwithamixtureofadrachmofconcentratedsolutionofthegreensulphateofironandtwodrachmsandahalfofmucilageofgumarabic。

  Subsequently,however,ithasbeenfoundthatthesulphateofironproducesuponallthesaltsofsilvereffectsquiteasbeautifulasinthesuccinate。Ontheiodide,bromide,acetate,andbenzoate,theeffectsarefarmorepleasingandstriking。Whenpicturesareproduced,orthedormantcameraimagebroughtout,bytheagencyofsulphateofiron,itisremarkablehowrapidlytheeffecttakesplace。

  Engravingscanbethuscopiedalmostinstantaneously,andcameraviewsobtainedinoneortwominutesonalmostanypreparationofsilver。

  Thecommonsulphateofcoppersolutionhasthesameproperty。

  III。CHROMATYPE。

  Manyeffortshavebeenmadetorenderchromaticacidanactiveagentintheproductionofphotographs。M。Pontonusedapapersaturatedwithbichromateofpotash,andthiswasoneoftheearliestphotogenicprocesses。

  M。Becquerelimproveduponthisprocessbysizingthepaperwithstarchprevioustotheapplicationofthebichromateofpotashsolution,whichenabledhimtoconvertthenegativepictureintoapositiveone,bytheuseofasolutionofiodine,whichcombinedwiththatportionofthestarchonwhichthelighthadnotacted。Butbyneitheroftheseprocessescouldclearanddistinctpicturesbeformed。

  Mr。Hunthas,however,discoveredaprocesswhichissoexceedinglysimple,andtheresultingpicturesofsopleasingacharacter,that,althoughitisnotsufficientlysensitiveforuseinthecamera,itwillbefoundofthegreatestvalueforcopyingbotanicalspecimens,engravings,orthelike。

  Thepapertobepreparediswashedoverwithasolutionofsulphateofcopper——aboutonedrachmtoanounceofwater——andpartiallydried;

  itisthenwashedwithamoderatelystrongsolutionofbichromateofpotash,anddriedatalittledistancefromthefire。

  Paperthuspreparedmaybekeptanylengthoftime,inaportfolio,andarealwaysreadyforuse。

  Whenexposedtothesunshineforatime,varyingwiththeintensityofthelight,fromfivetofifteenortwentyminutes,theresultisgenerallyanegativepicture。

  Itisnowtobewashedoverwithasolutionofnitrateofsilver,whichimmediatelyproducesaverybeautifuldeeporangepictureuponalightdimcolored,orsometimesperfectlywhiteground。

  Thispicturemustbequicklyfixed,bybeingwashedinpurewater,anddried。Withregardtothestrengthofthesolutions,itisaremarkablefact,that,ifsaturatedsolutionsbeemployed,anegativepictureisfirstproduced,butifthesolutionsbethreeorfourtimestheirbulkofwater,thefirstactionofthesun’sraysdarkensthepicture,andthenaverybleachingeffectfollows,givinganexceedinglyfaintpositivepicture,whichisbroughtoutwithgreatdelicacybythesilversolution。

  Itisnecessarythatpurewatershouldbeusedforthefixing,asthepresenceofanymuriatedamagesthepicture,andherearisesanotherpleasingvariationoftheChromatype。

  Ifthepositivepicturebeplacedinaveryweaksolutionofcommonsalttheimageslowlyfadesout,leavingafaintnegativeoutline。Ifitnowberemovedfromthesalinesolution,dried,andagainexposedtosunshine,apositivepictureofalilaccolorwillbeproducedbyafewminutesexposure。

  Severalotherofthechromatesmaybeusedinthisprocess,butnoneissosuccessfulasthechromateofcopper。

  IV。ANTHOTYPE。

  Theexpressedjuice,alcholic,orwateryinfusionofflowers,orvegetablesubstances,maybemadethemediaofphotogenicaction。

  ThisfactwasfirstdiscoveredbySirJohnHerschel。

  Wehavealreadygivenafewexamplesofthisinthethirdchapter。

  Certainprecautionsarenecessaryinextractingthecoloringmatterofflowers。Thepetalsoffreshflowersarecarefullyselected,andcrushedtoapulpinamarblemortar,eitheraloneorwiththeadditionofalittlealcohol,andthejuiceexpressedbysqueezingthepulpinacleanlinenorcottoncloth。

  Itisthentobespreaduponpaperwithaflatbrush,anddriedintheairwithoutartificialheat。Ifalcoholbenotadded,theapplicationonpapermustbeperformedimmediately,astheair(eveninafewminutes),irrecoverablychangesordestroystheircolor。

  Ifalcoholbepresentthischangeismuchretarded,andinsomecasesisentirelyprevented。

  Mostflowersgiveouttheircoloringmattertoalcoholorwater。

  Some,however,refusetodoso,andrequiretheadditionofalkalies,othersofacid,&c。Alcoholhas,however,beenfoundtoenfeeble,andinmanycasestodischargealtogetherthesecolors;buttheyare,inmostcases,restoredupondrying,whenspreadoverpaper。

  Paperstingedwithvetegablecolorsmustalwaysbekeptinthedark,andperfectlydry。

  Thecolorofaflowerisbynomeansalways,orusually,thatwhichitsexpressedjuiceimpartstowhitepaper。

  SirJohnHerschelattributesthesechangestotheescapeofcarbonicacidinsomecases;toachemicalalteration,dependingupontheabsorptionofoxygen,inothers;andagaininothers,especiallywheretheexpressedjuicecoagulatesonstanding,toalossofvitality,ordisorganizationofthemolecules。

  Tosecureanevenessoftintonpaper,thefollowingmanipulationisrecommended:——Thepapershouldbemoistenedonthebackbyspongingandblottingoff。Itshouldthenbepinnedonaboard,themoistsidedownwards,sothattwoofitsedges(supposetheright-handandlowerones)shallprojectalittlebeyondthoseoftheboard。Theboardthenbeinginclinedtwentyorthirtydegreestothehorizon,thealcoholictincture(mixedwithaverylittlewater,ifthepetalsthemselvesbenotveryjuicy)istobeappliedwithabrushinstrokesfromlefttoright,takingcarenottogoovertheedgeswhichrestontheboard;buttopassclearlyoverthosethatproject;

  andobservingalsotocarrythetintfrombelowupwardsbyquicksweepingstrokes,leavingnodryspacesbetweenthem,butkeepingupacontinuityofwetspaces。Whenalliswet,crossthembyanothersetofstrokesfromabovedownwards,somanagingthebrushastoleavenofloatingliquidonthepaper。

  Itmustthenbedriedasquicklyaspossibleoverastove,orinawarmcurrentofair,avoiding,however,suchheatasmayinjurethetint。

  Inadditiontotheflowersalreadymentionedinmythirdchapter,thefollowingareamongthoseexperimenteduponandfoundtogivetolerablegoodphotographicsensitives。Icanonlyenumeratethem,referringthestudent,foranyfurtherinformationhemaydesireonthesubject,toMr。Hunt’swork;althoughwhatIhavesaidaboveissufficientforallpracticalpurposes;andanyone,withtheambition,canreadilyexperimentuponthem,withoutfurtherresearch,onanyotherflowerhemaychoose。

  ViolaOdorata——orsweetsentedviolet,yieldstoalcoholarichbluecolor,whichitimpartsinhighperfectiontopaperSenecioSplendens——ordoublepurplegroundsel,yieldsabeautifulcolortopaper。

  Theleavesofthelaurel,commoncabbage,andthegrasses,arefoundsufficientlysenstive。

  CommonMerrigoldyieldsaninvaluablefaecula,whichappearsidenticalwiththatproducedbytheWall-flower,andCochorusjaponicamentionedbefore,andisverysensitive,butphotographsprocureduponitcannotbepreserved,thecolorissofugitive。

  FromanexaminationoftheresearchesofSirJohnHerschelonthecoloringmatterofplants,itwillbeseenthattheactionofthesun’sraysistodestroythecolor,effectingasortofchromaticanalysis,inwhichtwodistinctelementsofcolorareseparated,bydestroyingtheoneandleavingtheotheroutstanding。

  Theactionisconfinedwithinthevisiblespectrum,andthusabroaddistinctionisexhibitedbetweentheactionofthesun’sraysonvegetablejuicesandonargentinecompounds,thelatterbeingmostsensiblyaffectedbytheinvisibleraysbeyondtheviolet。

  Itmayalsobeobserved,thattherayseffectiveindestroyingagiventint,areinagreatmanycases,thosewhoseunionproducesacolorcomplementarytothetintdestroyed,or,atleast,onebelongingtothatclassofcolorstowhichsuchcomplementarytintmaybepreferred。

  Forinstance,yellowstendingtowardsorangearedestroyedwithmoreenergybythebluerays;bluesbythered,orangeandyellowrays;

  purplesandpinksbyyellowandgreenrays。

  V。AMPHITYPE。

  ThisprocessisadiscoveryofSirJohnHerschelandreceivesitsnamefromthefactthatbothnegativeandpositivephotographscanbeproducedbyoneprocess。Thepositivepicturesobtainedbyithaveaperfectresemblancetoimpressionsofengravingswithcommonprinter’sink。

  Theprocess,althoughnotyetfullycarriedout,promisestobeofvastutility。

  Paperproperforproducinganamphitypepicturemaybepreparedeitherwiththeferro-tartrateortheferro-citrateoftheprotoxide,ortheperoxideofmercury,oroftheprotoxideoflead,byusingcreamsofthesesalts,orbysuccessiveapplicationsofthenitratesoftherespectiveoxides,singlyorinmixture,tothepaper,alternatingwithsolutionsoftheammonia-tartrateortheammonia-citrateofiron,thelattersolutionbeinglastapplied,andinmoreorlessexcess。Ipurposelyavoidstatingproportions,asIhavenotyetbeenabletofixuponanywhichcertainlysucceed。

  Papersopreparedanddriedtakesanegativepicture,inatimevaryingfromhalfanhourtofiveorsixhours,accordingtotheintensityofthelight;andtheimpressionproducedvariesinapparentforcefromafaintandhardlyperceptiblepicturetooneofthehighestconceivablefulnessandrichnessbothoftintanddetail,thecolorbeinginthiscaseasuperbvelvetybrown。

  Thisextremerichnessofeffectisnotproducedunlessleadbepresent,eitherintheingredientsused,orinthepaperitself。

  Itisnot,asIoriginallysupposed,duetothepresenceoffreetartaricacid。Thepicturesinthisstatearenotpermanent。

  Theyfadeinthedark,thoughwithverydifferentdegreesofrapidity,some(especiallyiffreetartaricorcitricacidbepresent)inafewdays,whileothersremainforweeksunimpaired,andrequirewholeyearsfortheirtotalobliteration。

  Butthoughentirelyfadedoutinappearance,thepictureisonlyrendereddormant,andmayberestored,changingitscharacterfromnegativetopositive,anditscolorsfrombrowntoblack,(intheshadows),bythefollowingprocess:——Abathbeingpreparedbypouringasmallquantityofsolutionofpernitrateofmercuryintoalargequantityofwater,andlettingthesubnitratedprecipitatessubside,thepicturemaybeimmersedinit,(carefullyandrepeatedlyclearingoffallairbubbles,)

  andallowedtoremaintillthepicture(ifanywherevisible,)

  isentirelydestroyed;oriffaded,tillitisjudgedsufficientfrompreviousexperience;atermwhichisoftenmarkedbytheappearanceofafeeblepositivepicture,ofabrightyellowhue,onthepaleyellowgroundofthepaper。Alongtime(severalweeks)

  isoftenrequiredforthis,butheatacceleratestheaction,anditisoftencompletedinafewhours。Inthisstatethepictureistobeverythoroughlyrinsedandsoakedinpurewarmwater,andthendried。Itisthentobewellironedwithasmoothiron,heatedsoasbarelynottoinjurethepaper,placingit,forgreatersecurityagainstscorching,betweencleansmoothpaper。

  Ifthentheprocesshavebeensuccessful,aperfectlyblackpositivepictureisatoncedeveloped。Atfirstitmostcommonlyhappensthatthewholepictureissootyordingytosuchadegreethatitiscondemnedasspoiled,butonkeepingitbetweentheleavesofabook,especiallyinamoistatmosphere,byextremelyslowdegreesthisdinginessdisappears,andthepicturedisengagesitselfwithcontinuallyincreasingsharpnessandclearness,andacquirestheexacteffectofacopper-plateengravingonapapermoreorlesstintedwithapaleyellow。

  Ioughttoobserve,thatthebestandmostuniformspecimenswhichI

  haveprocuredhavebeenonpaperpreviouslywashedwithcertainpreparationsofuricacid,whichisaveryremarkableandpowerfulphotographicelement。Theintensityoftheoriginalnegativepictureisnocriterionofwhatmaybeexpectedinthepositive。

  Itisfromtheproductionbyoneandthesameactionoflight,ofeitherapositiveornegativepictureaccordingtothesubsequentmanipulations,thatIhavedesignatedtheprocess,thusgenerallysketchedout,bythetermAmphitype,——anamesuggestedbyMr。Talbot,towhomIcommunicatedthissingularresult;

  andtothisprocessorclassofprocesses(whichIcannotdoubtwhenpursuedwillleadtosomeverybeautifulresults,)

  Iproposetorestrictthenameinquestion,thoughitappliesevenmoreappropriatelytothefollowingexceedinglycuriousandremarkableone,inwhichsilverisconcerned:

  AtthelastmeetingIannouncedamodeofproducing,bymeansofasolutionofsilver,inconjunctionwithferro-tartaricacid,adormantpicturebroughtintoaforciblenegativeimpressionbythebreathormoistair。(SeeCyanotype。)Thesolutionthendescribed,andwhichhadatthattimebeenpreparedsomeweeks,Imayhereincidentallyremark,hasretaineditslimpidityandphotogenicproperties,quiteunimpairedduringthewholeyearsinceelapsed,andisnowassensitiveasever,——

  apropertyofnosmallvalue。Now,whenapicture(forexampleanimpressionfromanengraving)istakenonpaperwashedwiththissolution,itshowsnosignofapictureonitsback,whetherthatonitsfaceisdevelopedornot;butif,whiletheactinicinfluenceisstillfreshupontheface,(i。e。,assoonasitisremovedfromthelight),thebackbeexposedforaveryfewsecondstothesunshine,andthenremovedtoagloomyplace,apositivepicture,theexactcomplementofthenegativeoneontheotherside,thoughwantingofcourseinsharpnessifthepaperbethick,slowlyandgraduallymakesitsappearancethere,andinhalfanhouroranhouracquiresaconsiderableintensity。

  Ioughttomentionthatthe\"ferro-tartaricacid\"

  inquestionispreparedbyprecipitatingtheferro-tartrateofammonia(ammonia-tartrateofiron)byacetateoflead,anddecomposingtheprecipitatebydilutesulphuricacid。

  WhenleadisusedinthepreparationofAmphitypepaper,thepartsuponwhichthelighthasactedarefoundtobeinaveryhighdegreerenderedwaterproof。——SirJ。Herschel。

  Thisprocessisanewinventionofourcountryman,J。A。Whipple,Esq。,ofBoston,andhasbeenpatentedbyM。A。Root,Esq。,ofPhiladelphia。

  Itwillbeseen,however,fromthepreviouspagesofmyworkthatMr。Rootismistakeninregardtohisbeingthefirstimprovementpatentedinthiscountry,althonghitisunquestionablythefirstbyanAmerican。

  OfthisimprovementMr。Rootsays:

  VI。\"CRAYONDAGUERREOTYPE。\"

  \"Theimprovementtowhichyoureferisdenominated\"TheCrayonDaguerreotype。\"ThisinventionmadebyMr。J。A。Whipple,istheonlyimprovementinDaguerreotyping,Ibelieve,forwhichLettersPatentfortheUnitedStateswereeverissued。

  Thepicturesproducedbythisprocess——whichisofthesimplestdescriptionimaginable——havetheappearanceandeffectofveryfine\"CrayonDrawings,\"fromwhichtheimprovementtakesitsname。

  Someofourmostdistinguishedartistshavegivenittheirunqualifiedadmiration。Amongthem,ourMezzotintoEngravers,especiallyJohnSartain,Esq。,who,fromhisrichembellishmentstomostoftheleadingMagazinesandAnnualsofthecountry,aswellasfromthecelebrityofthesuperbMagazinewhichbearshisname,issowellknownandsowellqualifiedtojudgeofitsmerits。Asanauxiliarytotheartist,infurnishingheadstotheMagazines,orotherworks,itisinvaluable;

  thegreatobjectwhichitaccomplishesbeingtogiveafinereffectandmoredistinctexpressiontoallthefeatures——

  thewholepoweroftheinstrumentbeingdirectedto,andconfinedtothehead。\"

  \"Thelatehouratwhichthissubjecthasbeenbroughttoournoticepreventssofulladescriptionaswewouldotherwisehavebeengladtofurnish。TheNewEnglandStateshavebeendisposedof;

  negotiationsforanyoftheotherscanbemadethroughM。A。Root,140Chestnutstreet,Philadelphia。\"

  \"Aseriesofbeautifulportraitsareaboutbeingpreparedbythe\"CraytonProcess\"fortheexpresspurposeofbeingplacedontheexhibitionatthe\"ArtUnion,\"whenamateurs,artists,andthepublicgenerallywillhaveanopportunityofwitnessingitseffect。

  Weareespeciallygratifiedwiththisstrikingimprovement,fromtheadvantageswhichitpromisestotheDaguerreanart。\"

  \"Itisadmirablydesignedtoexciteanewinterestonthesubjectthroughthecommunity,andinthisway——andfromitstendencytorendertheartmoregenerallyuseful,andtoelevateanddistinguishit——

  tomakeittoallamatterofmoregeneralimportance。\"

  \"Yoursrespectfully,\"M。A。ROOT。\"

  Inoursecondedition,wehope——withMr。Root’spermission——

  tolaythewholeprocessbeforethepublic,althoughourartistsmustbearinmindthatMr。Root’spatentsecurestohimtheexclusiverightofitsapplication。

  CHAP。XI。

  ONTHEPROBABILITYOFPRODUCINGCOLOREDPICTURESBYTHESOLARRADIATIONS——

  PHOTOGRAPHICDEVIATIONS——LUNARPICTURES——DRUMMONDLIGHT。

  HavingbeforenoticedthefactthatsomeadvanceshadbeenmadetowardstakingDaguerreotypesincolor,bymeansofsolarrays,andexpressedthehopethatthedaywasnotfardistantwhenthismightbeaccomplished,IheresubjoinMr。Hunt’sremarksonthissubject。

  Mr。Biot,in1840,speakingofMr。FoxTalbot’sbeautifulcalotypepictures,considersasanillusion\"thehopetoreconcile,notonlytheintensitybutthetintsofthechemicalimpressionsproducedbyradiations,withthecolorsoftheobjectfromwhichtheseradiationsemanated。\"

  Itistruethatthreeyearshavepassedaway,andwehavenotyetproducedcoloredimages;yetIamnotinclinedtoconsiderthehopeasentirelyillusive。

  Itmustberememberedthatthecolorofbodiesdependsentirelyuponthearrangementoftheirmolecules。

  Wehavenumerousverybeautifulexperimentsinproofofthis。

  Thebi-niodideofmercuryisafinescarletwhenprecipitated。

  Ifthisprecipitateisheatedbetweenplatesofglass,itisconvertedintocrystalsofafinesulphuryellow,whichremainofthatcolorifundisturbed,butwhichbecomesveryspeedilyscarletiftouchedwithanypointedinstrument。

  ThisverycuriousopticalphenomenahasbeeninvestigatedbyMr。TalbotandbyMr。Warrington。Perfectlydrysulphateofcopperiswhite;theslightestmoistureturnsitblue。

  Muriateofcobaltisofapalepinkcolor;averyslightheat,byremovingalittlemoisture,changesittoagreen。

  Theseareafewinstancesselectedfrommanywhichmightbegiven。

  Ifwereceiveaprismaticspectrumonsomepapers,wehaveevidencethatthemolecularorchemicaldisturbancebearssomerelationtothecolorofeachray,or,inotherwords,thatcoloredlightsomodifiestheactionofENERGIA

  thattheimpressionitmakesisinproportiontothecolorofthelightitaccompanies,andhencethereresultsamoleculararrangementcapableofreflectingcolorsdifferently。

  Someinstanceshavebeengiveninwhichtheraysimpressedcorrespondwiththecolorsoftheluminousraysinaveryremarkablemanner。*Oneofthemostdecidedcasesisthatofthepaperpreparedwiththefluorideofsodaandnitrateofsilver。

  SirJohnHerschelwas,however,thefirsttoobtainanygoodspecimensofphotographicallyimpressedprismaticcolorations。

  *SeeMr。Hunt’s\"ResearchesonLight。\"

  ItwasnoticedbyDaguerrethataredhousegaveareddishimageonhisiodizedsilverplateinthecameraobscura;

  andMr。Talbotobserved,veryearlyinhisresearches,thattheredofacoloredprintwascopiedofaredcolor,onpaperspreadwiththechlorideofsilver。**

  **In1842,IhadshownmeapictureofahouseintheBowery,whichhadbeenrepairedafewdaysprevious,andinthewallaredbrickleft。ThisbrickwasbroughtoutontheDaguerreotypeplateofpreciselythesamecolorasthebrickitself。

  Thesameartistalsoexhibitedtome,thefulllengthportraitofagentlemanwhowereapairofpantaloonshavingabluestripedfigure。

  Thisbluestripewasfullybroughtout,ofthesamecolor,inthepicture。——AMER。ED。

  \"In1840IcommunicatedtoSirJohnHerschelsomeverycuriousresultsobtainedbytheuseofcoloredmedia,whichhedidmethehonorofpublishinginoneofhismemoirsonthesubjectfromwhichIagaincopyit。\"

  \"Apaperpreparedwithmuriateofbarytesandnitrateofsilver,allowedtodarkenwhilstwetinthesunshinetoachocolatecolor,wasplacedunderaframecontainingared,ayellow,agreen,andablueglass。

  Afteraweek’sexposuretodiffusedlight,itbecameredundertheredglass,adirtyyellowundertheyellowglass,adarkgreenunderthegreen,andalightoliveundertheblue。

  \"Theabovepaperwashedwithasolutionofsaltofiodine,isverysensitivetolight,andgivesabeautifulpicture。

  Apicturethustakenwasplacedbeneaththeaboveglasses,andanotherbeneathfourflatbottlescontainingcoloredfluids。

  Inafewdays,undertheredglassandfluid,thepicturebecameadarkblue,undertheyellowalightblue,underthegreenitremainedunchanged,whilstundertheblueitbecamearosered,whichinaboutthreeweekschangedintogreen。

  Manyotherexperimentsofasimilarnaturehavebeentriedsincethattimewithlikeresults。

  \"Inthesummerof1843,whenengagedinsomeexperimentsonpaperspreparedaccordingtotheprinciplesofMr。Talbot’scalotype,Ihadplacedinacameraobscuraapaperpreparedwiththebromideofsilverandgallicacid。

  Thecameraembracedapictureofaclearbluesky,stucco-frontedhouses,andagreenfield。Thepaperwasunavoidablyexposedforalongerperiodthanwasintended——aboutfifteenminutes,——averybeautifulpicturewasimpressed,which,whenheldbetweentheeyeandthelight,exhibitedacuriousorderofcolors。Theskywasofacrimsonhue,thehousesofaslatyblue,andthegreenfieldsofabrickredtint。

  Surelytheseresultsappeartoencouragethehope,thatwemayeventuallyarriveataprocessbywhichexternalnaturemaybemadetoimpressitsimagesonpreparedsurfaces,inallthebeautyoftheirnativecoloration。\"

  PHOTOGRAPHICDEVIATIONS。

  Beforetakingleaveofthesubjectofphotogenicdrawing,Imustmentiononeortwofacts,whichmaybeofessentialservicetooperators。

  IthasbeenobservedbyDaguerre,andothers,inEurope,andprobablybysomeofourownartists,thatthesuntwohoursafterithaspassedthemeridian,ismuchlesseffectiveinthephotographicprocess,thanitistwohoursprevioustoitshavingreachedthatpoint。

  Thismaydependuponanabsorptivepoweroftheair,whichmayreasonablybesupposedtobemorechargedwithvaportwohoursbeforenoon。

  Thefuseofthehygrometermaypossiblyestablishthetruthorfalsityofthissupposition。Thefact,however,ofabetterresultbeingproducedbeforenoonbeingestablished,personswishingtheirportraitstaken,willseetheadvantageofobtaininganearlysitting,iftheywishgoodpictures。

  Ontheotherhand,ifthesuppositionabovementionedprovetrue,atooearlysittingmustbeavoided。

  Ifwetakeaconsiderablethicknessofadensepurplefluid,as,forinstance,asolutionoftheammonia-sulphateofcopper,weshallfindthatthequantityoflightisconsiderablydiminished,atleastfour-fifthsoftheluminousraysbeingabsorbed,whilethechemicalrayspermeateitwiththegreatestfacility,andsensitivepreparationsareaffectedbyitsinfluence,notwithstandingthedeficiencyoflight,nearlyaspowerfullyasifexposedtotheundecomposedsunbeams。

  Itwasfirstimaginedthat\"underthebrilliantsunandclearskiesofthesouth,photographicpictureswouldbeproducedwithmuchgreaterquicknessthantheycouldbeintheatmosphereofParis。

  Itisfound,however,thatamuchlongertimeisrequired。

  EvenintheclearandbeautifullightofthehigherAlps,ithasbeenprovedthattheproductionofthephotographicpicturerequiresmanyminutesmore,evenwiththemostsensitivepreparations,thanitdoesinLondon。

  IthasalsobeenfoundthatunderthebrilliantlightofMexico,twentyminutes,andhalfanhour,arerequiredtoproduceeffectswhichinEnglandwouldoccupybutaminute;andtravellersengagedincopyingtheantiquitiesofYucatanhaveonseveraloccasionsabandonedtheuseofthephotographiccamera,andtakentotheirsketchbooks。

  Dr。Draper*hasobservedasimilardifferencebetweenthechemicalactionoflightinNewYorkandVirginia。ThiscanbeonlyexplainedbythesuppositionthattheintensityofthelightandheatoftheseclimesinterfereswiththeactionoftheENERGICraysonthosesensitivepreparationswhichareemployed。

  *Iwouldheretakeoccasiontoremarkthatourcountryman,Dr。Draper,isveryfrequentlyquotedbyMr,Huutinhis\"Researches。\"

  LUNARPICTURES——DRUMMONDLIGHT。

  TheRomanAstronomersstatethattheyhaveprocuredDaguerreotypeimpressionsoftheNebulaoftheswordofOrion。

  SignorRondinihasasecretmethodofreceivingphotographicimagesonlithographicstone;onsuchapreparedstonetheyhavesucceededinimpressinganimageoftheNebulaanditsstars;\"andfromthatstonetheyhavebeenenabledtotakeimpressionsonpaper,unlimitedinnumber,ofsingularbeauty,andofperfectprecision。\"

  Experimentshave,however,provedthat\"noheatingpowerexistsinthemoon’srays,andthatlunarlightwillnotactchemicallyupontheiduretofsilver。\"

  Itwasatonetimesupposedthatterrestrialorartificiallightpossessednochemicalrays,butthisisincorrect——Mr。Brandediscoveredthatalthoughtheconcentratedlightofthemoon,orthelightevenofolefiantgas,howeverintense,hadnoeffectonchlorideofsilver,oronamixtureofchlorideandhydrogen,yetthelightemittedbyelecterizedcharcoalblackensthesalt。

  AttheRoyalPolytechnicInstitutionpictureshavebeentakenbymeansofsensitivepaperacteduponbytheDrummondLight;

  butitmustofcoursebedistinctlyunderstood,thattheyareinferiortothosetakenbythelightofthesun,ordiffuseddaylight。

  Ifouroperatorscouldmanagetoproducegoodpicturesinthiswaytheywouldputmoneyintheirpockets,asmanywhocannotfindtimeduringthedaywouldresorttotheirroomsatnight。

  Ithrowoutthehintinhopessomeonewillmaketheexperiment。

  Ihavelearned,sincetheabovewaswritten,thatanoperatorinBostonsucceededashorttimesinceinprocuringverygoodpicturesbytheaidoftheDrummondLight;butthattheintensityofthelightfallingdirectlyuponthesitter’sfacecausedgreatdifficulty,andheabandonedit。

  Thismay,probably,beremediedbyinterposingascreenofverythintissuepapertingedslightlyofabluishcolor。

  CHAP。XII。

  ONCOLORINGDAGUERREOTYPES。

  Nearly,ifnotquiteallthevariouscolorsusedinpaintingmaybemadefromthefiveprimitivecolors,black,white,blue,redandyellow,butfortheDaguerreanartistitwouldbethebestpolicytoobtainsuchasarerequiredbytheirartalreadyprepared。Inamajorityofcases,thefollowingwillbefoundsufficient,viz。

  Carmine。

  PrussianBlue。

  White。

  ChromeYellow,Gamboge,YellowOchre;orallthree。*

  *Gambogeisbestfordrapery;Ochrefortheface。

  LightRed。

  Indigo。

  BurntSienna。

  Bistre,orBurntUmber。

  If,incoloringanypartofalady’sorgentleman’sapparel,itisfoundnecessarytoproduceothertintsandshades,thefollowingcombinationsmaybeused:

  Orange——Mixyellowwithred,makingitdarkerorlighterbyusingmoreorlessred。

  Purple——ThisismadewithPrussianblue,orindigoandred。

  CarmineandPrussianblueproducingtherichestcolor,whichmaybedeepenedintheshadowsbyaslightadditionofindigoorbrown。

  Greens——Prussianblueandgambogemakesaveryfinegreen,whichmaybevariedtosuitthetasteofthesitteroroperator,bylargerportionsofeither,orbyaddingwhite,burntsienna,indigo,andred,asthecasemayrequire。

  Thesecombinations,underdifferentmodifications,givealmostendlessvarietiesofgreen。

  Brown——Maybemadeofdifferentshadesofumber,carmineandlamp-black。

  Neutraltint——Iscomposedofindigoandlamp-black。

  Crimson——Mixcarmineandwhite,deepeningtheshadedpartsofthepicturewithadditionalcarmine。

  FleshColor——Thebestrepresentativeoffleshcolorislightred,brightenedinthemoreglowingorwarmerparts,withcarmine,softenedoffinthelighterportionswithwhite,andshadedwithpurpleandburntsienna。

  LeadColor——Mixindigoandwhiteinproportionstosuit。

  Scarlet——Carmineandlightred。

  ForJewelrycupsofgoldandsilverpreparationsaccompanyeachboxforDaguerreotypists,ormaybeprocuredseparately。

  ThemethodoflayingcolorsonDaguerreotypesisoneofconsiderabledifficulty,inasmuchastheyareusedintheformofperfectlydryimpalpablepowder。Theauthorofthislittleworkisnowexperimenting,inorder,ifpossible,todiscoversomemoreeasy,artisticandunexceptionablemethod。

  Ifsuccessful,theresultwillbepublishedinafutureedition。

  TherulesweshallgiveforcoloringDaguerreotypesdepends,andarefounded,uponthoseobservedinminiaturepainting,andareintendedmoreashintstoDaguerreanartists,inhopesofleadingthemtoattemptimprovements,thanasinstructionswhollytobeobserved。

  Thewriterisconfidentthatsomecompoundoringredientmayyetbediscoveredwhich,whenmixedwiththecolors,willgiveamoredelicate,pleasing,andnaturalappearancetothepicturethanisderivedfromthepresentmodeoflayingthemon,whichinhisestimationismorelikeplasteringthancoloring。

  INCOLORINGDAGUERREOTYPES,theprincipalshadesoftheheadaretobemadewithbistre,mixedwithburntsienna,touchingsomeplaceswithamixtureofcarmineandindigo。

  Thefleshtintsareproducedbytheuseoflightred,deepenedtowardstheshadedpartswithyellowochre,blueandcarminemixedwithindigo,whilethewarmer,ormorehighlycoloredpartshaveaslightexcessofcarmineorlake。

  Colortheshadesaboutthemouthandneckwithyellowochre,blue,andaverylittlecarmine,heighteningthecolorofthelipswithcarmineandlightred,lettingthelightredpredominateontheupper,andthecarmineonthelowerlip;

  theshadesinthecornerofthemouthbeingtouchedslightlywithburntsienna,mixedwithcarmine。

  Incoloringtheeyes,theartistwillofcoursebeguidedbynature,observingaverydelicatetouchinlayingonthecolors,soastopreserveasmuchtransparencyaspossible。Aslighttouchofblue——

  ultramarinewouldbebestifitwouldadheretotheDaguerreotypeplate——

  inthewhitesoftheeyeneartheiris,willproduceagoodeffect。

  Incoloringtheheadsofmenitwillbenecessarytousethedarkertintswithmorefreedom,accordingtothecomplexionofthesitter。

  Forwomen,thewarmertintsshouldpredominate,andinordertogivethattransparencysouniversalwiththesoftersex——

  andwhichgivessomuchlovelinessandbeautytotheface——

  alittlewhitemaybejudiciouslyintermingledwiththeredtintsaboutthelighterportionsoftheface。

  Intakingapictureofaladywithlightorauburnhair,bytheDaguerreanprocess,muchofthebeautyofthefaceisdestroyed,onaccountoftheimperfectmannerinwhichlightconveystheimageoflightobjectstothespectrumofthecamera。

  Thismaybeobviatedinsomemeasurebypropercoloring。

  Todothis,touchtheshadedpartswithburntsiennaandbistre,fillingupthelighterportionswithyellowochre,delicatetouchesofburntsienna,andinthosepartswhichnaturallyhaveabluishtint,addverydelicatetouchesofpurple——

  sodelicateinfactashardlytobeperceived。Therootsofthehairattheforeheadshouldalsobetouchedwithblue,andtheeyebrowsnearthetemplesmadeofapinkishtint。

  Thechinofawomanisnearlyofthesamecolorasthecheeksinthemostglowingparts。Inmenitisstronger,andofabluishtint,inordertoproducetheeffectgivenbythebeard。

  Inportraitsofwomen——themiddletintsonthesideofthelight,whichareperceivedonthebosomandarms,aremadeofaslightmixtureofochre,blueandlake,(orcarmine),towhichadd,ontheshadedsides,ochre,bistreandpurple,thelatterinthedarkerparts。

  Thetintsofthehandsshouldbethesameastheotherpartsoftheflesh,theendsofthefingersbeingalittlepinkishandthenailsofaviolethue。

  Ifanyportionofthefleshypartsisshadedbyportionsofthedress,orbythepositionofthehand,thisshadeshouldbecoloredwithumbermixedwithpurple。

  TOCOLORTHEDRAPERY。——VioletVelvet——UsepurplemadeofPrussianblueandcarmine,touchinguptheshadedpartswithindigoblue。

  GreenVelvet——MixPrussianblueandred-orpiment,shadewithpurple,andtouchupthelightswithalittlewhite。

  RedVelvet——Mixaverylittlebrownwithcarmine,shadingwithpurple,markingthelightsinthestrongestpartswithpurecarmine,andtouchthemostbrilliantslightlywithwhite。

  WhiteFeathers——Maybeimprovedbydelicatelytouchingtheshadedpartswithalittlebluemixedwithwhite。

  Whitemuslin,linen,lace,satin,silk,etc。,mayalsobecoloredinthesameway,beingcarefulnottolaythecolorontooheavily。

  FURS——RedFursmaybeimitatedbyusinglightredandalittlemasticot,shadedwithumber。GrayFurs——blackandwhitemixedandshadedwithbistre。

  Sable——whiteshadedlightlywithyellowochre。

  Thesefewdirectionsarequitesufficientfortheart,anditisquiteunnecessaryformetopursuethesubjectfurther。

  Iwould,however,remarkthattheDaguerreotypistswouldfinditgreatlytotheiradvantagetovisitthestudiesofourbestartists,ourpublicgalleriesofpaintings,andstatuary,andwhereverelsetheycanobtainasightoffinepaintings,andstudythevariousstylesofcoloring,atitudes,foldsofdraperyandotherpointsoftheart。

  IncoloringDaguerreotypes,artistswillfindthemagnifyingglassofmuchadvantageindetectinganyimperfectionsintheplateorintheimage,whichmayberemediedbythebrush。

  Inselectingbrusheschoosethosemostsusceptibleofafinepoint,whichmaybeescertainedbywettingthembetweenthelips,orinaglassofwater。

  CHAP。XIII。

  THEPHOTOGRAPHOMETER。

  Thelastnumber(forMarch,1849)ofthe\"LondonArt-Journal,givesthefollowingdescriptionofarecentimprovementinPhotographicManipulation,andasIamdesirousoffurnishingeverythingnewintheart,Istopthepresstoaddit,entire,tomywork。

  \"Sincethephotographicpowerofthesolarraysbearsnodirectrelationtotheirluminousinfluence,itbecomesaquestionofconsiderableimportancetothosewhopracticethebeautifulartofphotography,tohavethemeansofreadilymeasuringtheeverchangingactivityofthisforce。Severalplansmoreorlesssuccessful,havebeendevisedbySirJohnHerschel,Messrs。Jordan,ShawandHunt。

  Theinstrument,however,whichisnowbroughtforwardbyMr。Claudet,whoiswellknownasoneofourmostsuccessfulDaguerreotypists,appearsadmirablysuitedtoallthosepurposeswhichthepracticalmanrequires。Thegreatdifficultywhichcontinuallyannoysthephotographicamateurandartist,isthedeterminationofthesensibilityofeachtabletemployed,relativelytotheamountofradiation,luminousandchemical,withwhichheisworking。

  WiththephotographometerofMr。Claudetthisiseasilyascertained。

  Thefollowingwoodcutsandconcisedescriptionwillsufficientlyindicatethisusefulandsimpleapparatus。

  [hipho_30。gif]

  \"Foraninstrumentofthiskinditisimportantinthefirstplacetohaveamotionalwaysuniform,withoutcomplicatedorexpensivemechanism。Thisisobtainedbymeansfoundedupontheprincipleofthefallofbodiesslidingdownaninclinedplane。

  Thesensitivesurfaceisexposedtothelightbytherapidanduniformpassageofametalplate,A,B,(Fig。31,)havingopeningsofdifferentlength,whichfollowageometricprogression。

  Itisevidentthattheexposuretolightwillbethesameforeachexperiment,becausetheplatefurnishedwiththeproportionalopeningsfallsalwayswiththesamerapidity,theheightofthefallbeingconstant,andtheangleoftheinclinedplanethesame。

  Eachopeningofthismoveableplateallowsthelighttopassduringthesamespaceoftime,andtheeffectuponthesensitivesurfaceindicatesexactlytheintensityofthechemicalrays。

  Therapidityofthefallmaybeaugmentedordiminishedbyalteringtheinclinationoftheplanebymeansofagraduatedarc,C,D,(Fig。30,)furnishedwithascrew,E,bywhichitmaybefixedatanyangle。Thesameresultmaybeobtainedbymodifyingtheheightofthefallortheweightofthemoveableplate。

  Thephotogenicsurface,whether[hipho_31。gif]

  itbetheDaguerreotypeplate,theTalbotypepaper,oranyotherpreparationsensitivetolight,isplacednearthebottomoftheinclinedplane,F。Itiscoveredbyathinplateofmetal,piercedwithcircularholes,whichcorrespondtotheopeningsofthemoveableplateatthemomentofthepassageofthelatter,duringwhichthesensitivesurfacereceivesthelightwhereverthecircularholesleaveitexposed。

  \"Thepartoftheapparatuswhichcontainsthesensitivesurfaceisanindependentframe,anditslidesfromadarkboxintoanopeningonthesideoftheinclinedplane。

  \"Acoveringofblackclothimpermeabletolightis,attachedtothesidesofthemoveableplate,envelopingthewholeinclinedplane,rollingfreelyovertworollers,R,R,placedtheoneattheupperandtheotheratthelowerpartoftheinclinedplane。

  Thisclothpreventsthelightstrikingthesensitivesurfacebeforeandafterthepassageofthemoveableplate。

  \"Itwillbeseenthatthisapparatusenablestheexperimentalisttoascertainwithgreatprecisiontheexactlengthoftimewhichisrequiredtoproduceagivenamountofactinicchangeuponanysensitivephotographicsurface,whetheronmetalorpaper。

  Althoughatpresentsomecalculationisnecessarytodeterminethedifferencebetweenthetimewhichisnecessaryforexposureindirectradiation,andtotheactionofthesecondaryradiationsofthecameraobscura;thisis,however,averysimplematter,anditappearstousexceedinglyeasytoadaptaninstrumentofthisdescriptiontothecameraitself。

  \"BythisinstrumentMr。Claudethasalreadydeterminedmanyveryimportantpoints。Amongothers,hehasprovedthatonthemostsensitiveDaguerreotypeplateanexposureof。0001

  partofasecondissufficienttoproduceadecidedeffect。

  \"Regardingphotographyasanauxiliaryaidtotheartistofnomeanvalue,wearepleasedtorecordadescriptionofaninstrumentwhich,withoutbeingcomplicated,promisestobeexceedinglyuseful。Inthisopinionwearenotsingular;

  atarecentmeetingofthePhotographicClub,towhichthisinstrumentwasexhibited,itwaswithmuchrealsatisfactionthatwelearnedthatseveralofourmosteminentartistswerenoweagerandmostsuccessfulstudentsinPhotography。

  Thebeautifulproductionsofthemoreprominentmembersofthisclubexcitedtheadmirationofall,particularlythecopiesofarchitecturalbeauties,andsmallbitsoflandscape,byMessrs。

  CundellandOwen。Wethinkthatnowtheartistseestheadvantagehemayderivefromtheaidofscience,thatbothwillgainbytheunion。\"

  Ihopetheabovedescriptionwillinduceourtownsman,Mr。Roach,tosuccessfullyproduceaninstrumentthatwillmeetthewantsofourartistsinthatpartoftheDaguerreanprocessreferredto。

  FINIS。

  INDEX。

  AcceleratingLiquids。65

  Amphitype。116

  Anthotype。113

  Apparatus。Daguerreotype。43

  Calotype97

  Photogenic87

  ApplicationofPhotogenicDrawing。95

  ApplyingtheSensitive。64

  BringingoutthePicture。71

  BromineBox。51

  Chlorideof68

  Roach’sTrippleCompoundof67

  water。65

  BromideofIodine。67

  ofLime。68

  Paper。91

  ofsilver。35

  Brushes。88

  BuffSticks。60

  Calotypeprocess。97

  paper。ExposureinCameraof100

  Pictures。Bringingoutib。

  Fixing101

  Camera。Descriptionofthe43

  Stand。49

  Woodbridge’sib。

  Calotype。50

  Voigtlander45

  ChlorideofBromine。68

  ofGold。36

  tomakeasolutionof75

  ofIodine。66

  ofSilver。31

  Chromatype。112

  Chrysotype。106

  CleaningandPolishingtheplate。61

  CoatingBoxes。51

  ColorBoxes。53

  ColoredDaguerreotypesonCopper。77

  ColoringthePicture。76

  Daguerreotypes。129

  ConcaveMirrors。19

  ConvexMirrors19

  CorchorusJaponica。37

  CrayonDaguerreotypes。120

  Cyanotype109

  DaguerreotypeApparatus。43

  Process。61

  Plates。62

  Daguerreotypes。Crayon77

  onpaper81

  Dedication。iiiDefinitionsoftermsusedinoptics,15

  Differentmethodsofpreparingphotogenicpaper。89

  DirectionsforuseofGalvanicBattery。58

  Distilledwater88

  Drummondlight。128

  DrySensitive。68

  Dryingapparatus。72

  Effectsoflightonbodies25

  Energiatype111

  EtchingDaguerreotypes。83

  Fifthoperation。Fixingthepicture。61

  Firstoperation。Cleaningtheplate61

  Fluoricacid。69

  Fourthoperation-Bringingoutthepicture。71

  Funnels。53

  GalvanicBattery。57

  Solutionforuseof58

  Gildingstand。53

  thepicture。74

  Gold。Chlorideof36

  Tomakesolutionof75

  Hyposulphite;orSaltof74

  Preparationof。36

  Gurney’sSensitive。67

  HeadRests。57

  HintsandSuggestions。39

  HistoryofPhotography。3

  HungarianLiquid。69

  Hygrometers。55

  HyposulphiteofGold。74

  ofSoda。28

  InstantaneouspicturesbymeansofGalvanism。77

  Introduction。iIodine,Dry64

  Chlorideof66

  Bromideof67

  Box。51

  Iodideofsilver。32

  loduretofsilver。33

  IodizethePlate。To64

  IodizedPaperforCalotypes。Toprepare98

  TopreparefortheCameraib。

  Lamps,Spirit53

  Light。Theoryon14

  Motionof16

  Reflectionof17

  Refractionof20

  onbodies。Effectsof25

  Prismaticanalysisof22

  Lime,Bromideof68

  LunarPictures。127

  Mead’sAccelerator。68

  MercuryBath50

  NitrateofSilver。89

  OxideofSilver。29

  OncoloringDaguerreotypes129

  OntheprobabilityofProducingcoloredPhotographs。123

  Paper。blotting;orbibulous,88

  Daguerreotypes。81

  preparationof89

  suitableforPhotographs。87

  PhotogenicdrawingonibPhotographicprinciple,the22

  Photographicprocessonpaper。92

  drawing。Applicationof95

  Tofixthe93

  deviations。126

  Photographometer,The135

  PlateSupport。59

  Blocks。50

  Vice。51

  Poppy,TheRed37

  Porcelaindishes。59

  PositiveCalotype104

  Preface。vPreparationofIodizedPaper。98

  ofGold。36

  PrismaticSpectrum。22

  AnalysisofLight。ibReflectionofLight。17

  RefractionofLight。20

  Roach’sTrippleCompoundofBromine。67

  SandClock。70

  Sealingpaper。Tomake77

  Secondoperation。94

  Sensitive。ibSilver。Bromideof35

  Clorideof31

  Iodideof32

  Ioduretof33

  Nitrateof89

  Oxideof28

  SolutionofChlorideof59

  Sixthoperation。74

  SodaHyposulphiteof72

  SolarandStellarLight。21

  Stillforpurifyingwater,54

  SubmittingthePlatetotheactionofLight69

  SynopsisofMr。Hunt’sTreatiseonLight,29

  TalbotypeCamera。50

  TheoryonLight。14

  Thirdoperation。69

  WallFlower。37

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