the history and practice of the art of photography-第13节

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The　last　drop　may　now　be　removed　by　a　little　bibulous　paper。　A　single　drop；　even；　of　distilled　water　allowed　to　dry　on　any　part　of　the　surface；　is　certain　to　leave　a　stain　which　no　after　process　can　remove。

To　illustrate　the　necessity　for　having　perfectly　clean　water；　and　free　from　all　foreign　matteronly　to　be　avoided　by　using　that　which　is　distilled　in　these　processes；　I　will　relate　a　little　anecdote。

An　operator　in　this　city　（New　York）　frequently　made　complaint　to　me；　that　his　plates　were　occasionally　very　bad；　coming　out　all　over　in　little　black　and　white　spots　and　spoiling　many　very　good　pictures；　regretting　at　the　same　time　that　perfect　plates　were　not　made；　for　he　had　lost　many　customers　in　consequence　of　these　defects。　These　complaints　being　somewhat　periodical；　I　suggested　that　the　fault　might　be　in　the　hyposulphite；　or　chloride　of　gold　solutions；　or　particles　of　dust　floating　about　in　the　room；　and　not　in　the　plate。

A　few　days　after　he　stated；　that　his　plates　having　served　him　again　in　the　same　way；　he　procured　a　fresh　supply　of　hyposulphite　of　soda　and　chloride　of　gold；　but　after　applying　them　the　result　was　no　better。　He　then；　by　my　advice；　thoroughly　cleaned　his　wash　dishes；　bottles　and　water　pail；　made　fresh　solutions　and　had　no　further　trouble；　becoming　satisfied　that　the　plates　suffered　an　undue　share　of　censure。

SIXTH　PROCESS。Gilding　the　Picture。This　is　an　improvement　the　honor　of　which　is　due　to　M。　Figeau；　and　may　take　place　either　before　the　drying　process；　or　at　any　subsequent　period；　but　it　improves　the　picture　so　materially　that　it　should　never　be　neglected。　The　articles　necessary　for　gilding　are

A　Pair　of　Plyars；　or　a　Gilding　Stand　（see　fig。　19）　and　Chloride　of　Gold；　or　Hyposulphite　of　Gold。

The　latter　is　imported　by　Mr。　E。　Anthony；　205　Broadway；　New　York；　and　is　decidedly　the　best　article　for　the　purpose。　One　bottle　simply　dissolved　in　a　quart　of　water　will　make　a　very　strong　solution；　and　gives　a　richness　to　the　picture　impossible　to　be　obtained　from　the　chloride　of　gold。　The　process　is　precisely　similar　to　that　described　below　for　chloride　of　gold；　taking　care　to　cease　the　moment　the　bubbles　are　well　defined　over　the　surface　of　the　plate。　Many　Daguerreotypists；　after　a　superficial　trial；　discard　the　hyposulphite　of　gold　as　inferior；　but　I　have　no　hesitation　in　asserting　that　the　fault　lies　with　themselves；　for　in　every　case　within　my　knowledge；　where　its　use　has　been　persisted　in　until　the　correct　method　has　been　ascertained　and　the　nature　of　the　gilding　has　become　familiar；　it　is　always　preferred。　In　illustration　of　this　fact　I　will　relate　an　anecdote：

A　gentleman　to　whom　it　had　been　recommended；　purchased　a　bottle；　and　after　making　one　or　two　trials　of　it；　wrote　to　his　correspondent〃Send　me　two　bottles　of　chloride　of　gold；　for　I　want　no　more　of　the　hyposulphite；　it　is　good　for　nothing。〃　A　few　weeks　after　he　sent　for　three　bottles　of　the　condemned　article；　confessing　that　be　had　found　fault　unnecessarily；　for；　that　since　he　had　become　familiar　to　its　use；　he　must　acknowledge　its　superiority；　and　would　use　no　other　gilding。

The　Solution　of　Chloride　of　Gold　is　prepared　by　dissolving　in　a　pint　of　distilled　water；　fifteen　grains　of　chrystalized　chloride　of　gold。　This　solution　will　be　of　a　yellow　tint。　　In　another　pint　of　distilled　water　dissolve　fifty…five　grains　of　hyposulphite　of　soda；　pour　gradually；　in　very　small　quantities；　the　gold　into　the　hyposulphite　of　soda；　stirring　the　solution　at　intervals；　when　finished　the　mixture　should　be　nearly　colorless。

Place　the　plate　on　its　stand；　or　hold　it　in　the　plyers；　in　a　perfectly　horrizontal　positionsilver　surface　upwardhaving　previously　slightly　turned　up　the　edges；　so　that　it　may　hold　the　solution。　Wet　the　surface　with　alcohol；　letting　any　superfluous　quantity　drain　off。　The　alcohol　is　of　no　farther　use　than　to　facilitate　the　flowing　of　the　gold　mixture　over　the　surface。　　Now　pour　on；　carefully；　as　much　of　the　preparation　of　gold　as　will　remain　on　the　plate。　The　under　part　of　the　plate　is　then　to　be　heated　as　uniformly　as　possible　with　the　spirit　lamp；　small　bubbles　will　arrise；　and　the　appearance　of　the　portrait　or　view　very　sensibly　improved。　The　process　must　not　be　carried　too　far；　but　as　soon　as　the　bubbles　disappear　the　lamp　should　be　removed；　and　the　plate　immersed　in　distilled　water；　and　dried　as　before　directed。

7th。　COLORING　THE　PICTURE。I　very　much　doubt　the　propriety　of　coloring　the　daguerreotypes；　as　I　am　of　opinion；　that　they　are　little；　if　any；　improved　by　the　operation；　at　least　as　it　is　now　generally　practised。

There　are　several　things　requisite　in　an　artist　to　enable　him　to　color　a　head；　or　even　a　landscape　effectively；　and　correctly；　and　I　must　say　that　very　few　of　these　are　possessed　by　our　operators　as　a　class。　These　requirements　are；　a　talent　for　drawingtastedue　discrimination　of　effectstrict　observance　of　the　characteristic　points　in　the　features　of　the　subjectquick　perception　of　the　beautiful；　and　a　knowledge　of　the　art　of　mixing　colors；　and　blending　tints。

The　method　now　pursued；　I　do　not　hesitate　to　say；　and　have　no　fears　of　being　contradicted　by　those　capable　of　critisizing　is　on　the　whole　ruinous　to　any　daguerreotype；　and　to　a　perfect　one　absolutely　disgusting。　The　day　may　come　when　accurate　coloring　may　be　obtained　in　the　camera。　Until　that　day；　if　we　cannot　lead　taste　into　the　right　channel；　we　will　endeavor　to　give　such　instructions　that　Daguerreotypists　may　proceed　with　this　part　of　his　work　with　a　better　understanding　of　the　principles　involved。　For　this　purpose　I　have　prepared　a　short　chapter　on　the　art　of　coloring；　which　may　be　found　in　the　latter　part　of　this　volume。

To　Preserve　Daguerreotypes　they　must　be　well　sealed　and　secured　in　a　case；　or　frame。　　These；　of　course；　are　selected　according　to　the　taste　of　the　customer；　the　principal　requisite　being　good　glass。　Most　Daguerreotypists　prefer　the　white　French　plate　glassand　many　think；　very　erroneously；　that　none　is　good　unless　it　is　thick　but　the　great　desideratum　is　clearness　and　freedom　from　blisters；　even　glass　a　little　tinged　with　green　or　yellow　is　to　be　preferred　to　the　French　plate　when　cloudy　or　blistered　and　there　is　very　little　of　it　comes　to　this　market　that　is　not　so。　It　is　to　be　hoped　that　some　of　our　glass　factories　will　manage　to　manufacture　an　article　expressly　for　daguerreotypes；　and　I　would　recommend　them　to　do　so；　for　they　would　find　it　quite　an　item　of　profit　annually。

Before　enclosing　the　picture　in　the　case　you　should　be　careful　to　wipe　the　glass　perfectly　clean；　and　blow　from　the　picture　any　particles　of　dust　which　may　have　fallen　upon　it。　Then　take　strips　of　sticking　paper；　about　half　or　three　quarters　of　an　inch　wide；　and　firmly　and　neatly　secure　it　to　the　glass；　having　first　placed　a　〃mat〃　between　them　to　prevent　the　plate　being　scratched　by　the　glass。

TO　MAKE　SEALING　PAPER。Dissolve　one　ounce　of　gum　arabic；　and　a　quarter　of　an　ounce　of　gum　tragicanth　in　a　pint　of　water；　then　add　a　teaspoonful　of　benzoin。　　Spread　this　evenly　on　one　side　of　good　stout　tissue　paper；　let　it　dry；　and　then　cut　it　up　in　stripes；　about　half　or　three　quarters　of　an　inch　wide；　for　use。　If　it　becomes　too　soft　for　summer　use；　add　gum　arabic；　if　too　hard　and　cracking；　add　benzoin　or　gum　tragicanth；　if　it　gets　too　thick；　add　water。

COLORED　DAGUERREOTYPES　ON　COPPER。To　effect　this；　take　a　polished　plate　of　copper　and　expose　it　to　the　vapor　of　iodine；　or　bromine；　or　the　two　substances　combined；　or　either　of　them　in　combination　with　chlorine。　This　gives　a　sensitive　coating　to　the　surface　of　the　plate；　which　may　then　be　submitted　to　the　action　of　light　in　the　camera。　After　remaining　a　sufficient　time　in　the　camera；　the　plate　is　taken　out　and　exposed　to　the　vapor　of　sulphuretted　hydrogen。　This　vapor　produces　various　colors　on　the　plate；　according　to　the　intensity　with　which　the　light　has　acted　on　the　different　parts；　consequently　a　colored　photographic　picture　is　obtained。　No　further　process　is　necessary　as　exposure　to　light　does　not　effect　the　picture。

By　this　process　we　have　an　advantage　over　the　silvered　plate；　both　in　economy；　and　in　the　production　of　the　picture　in　colors。

INSTANTANTANEOUS　PICTURES　BY　MEANS　OF　GALVANISM。It　will　be　seen　by　the　following　valuable　communication　that　galvanism　can　be　successfully　applied　in　producing　pictures　instantly；　a　process　of　great　importance　in　securing　the　likeness　of　a　child；　or　in　taking　views　of　animated　nature。　Colonel　Whitney　informs　me　that　he　once　took　a　view　of　the　steeple　of　the　St。　Louis　Court　House　after　sundown　by　this　means）　and　also　secured　the　image　of　a　man　in　the　act　of　stepping　into　a　store；　and　before　he　had　time　to　place　his　foot；　raised　for　that　purpose；　on　the　door　step。　Mr。　Whitney　is　well　known　as　the　talented　editor　of　the　Sunday　Morning　news。


　New　York；　January　16；　1849。　　Mr。　H。　H。　SNELLING。

Dear　Sir；As　you　are　about　publishing　a　history　of　the　Daguerreotype；　and　request　a　description　of　my　mode　of　taking　pictures　instantaneously　by　the　aid　of　galvanism；　I　comply　with　great　pleasure。

In　the　year　1841；　while　practicing　the　art　in　St。　Louis；　Mo。；　I　was　at　times；　during　the　summer；　much　troubled　with　the　electric　influence　of　the　atmosphere；　especially　on　the　approach