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ined from time to time； by simply raising it with the fingers； or a pair of plyers。 This operation； as well as the others； should take place in the dark closet。 ＇hipho_26。gif＇ Sometimes； to prevent the necessity of raising the plate； an additional cover or top is made use of。 It consists of a box fitted closely to the inner rim of the bath； and having an inclined top （a； Fig。 27。） The top is cut through and fitted with frames for each size of plate； like those already described； and in the back is a piece of glass （b；） through which to view the progress of mercurialization； and an additional piece （c；） on one side； colored yellow； to admit the light。 The outline only of the top is here given； in order to show every portion of it at one view。
The picture； being fully developed； is now taken out and examined； it must not； however； be exposed to too strong a light。 If any glaring defects be perceived； it is better not to proceed with it； but place it on one side to be re…polished； if； on the contrary； it appears perfect； you may advance to the
FIFTH OPERATION。Fixing the Image so that the light can no longer act upon it。The following articles are required for this purpose：
Two or three porcelain or glass dishes； in form； something like fig。 24。
A plate support； fig。 25。 Few； I believe； now make use of this； although it is a very convenient article。
Hyposulphite of Soda；
A pair of Plyers。
In Europe； they also use a drying apparatus； Fig。 27； but this； like the plate support； ＇hipho_27。gif＇ is a matter of little consequence； and may be dispensed with。 I will； however； describe it； for the benefit of those who may wish to use it。
A vessel made of copper or brass； tinned inside； and large enough to take in the largest plate； but not more than half an inch wide； is the most convenient。 It must be kept perfectly clean。 Hot distilled water is poured into it； and the temperature kept up by a spirit lamp。
Hyposulphite of Soda。Having made a solution of hyposulphite of soda； and well filtered itthe strength is immaterial； about half an ounce of the salt to a pint of distilled water is sufficientpour it into one of the porcelain dishes； put into another plain； and into a third distilled water。 Immerse the plate with its face downwards into the hyposulphite； and the whole of the sensitive is removed； and the light has no farther action upon it； it is then to be removed from the hyposulphite and plunged into the plain water； or placed upon the support； fig。 25； and the water poured over it。 It is then washed in a similar manner with the distilled water and well examined； to see that not the slightest particle of dust rests on the suface。 The next step is to dry it。
This may be readily accomplished by holding the plate with your plyers； and pouring distilled water over itif it is hot； so much the better。 Apply the spirit lamp to the back； at the corner held by the plyers； at the same time facilitating the operation with the breath； pass the lamp gradually downwards； finishing at the extreme corner。 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 v