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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