This may be readily accomplished by holding the plate with your plyers, and pouring distilled water over it--if 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 matter--only 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 Plyers; 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 he 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 horizontal position--silver surface upward--having 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 arise, 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 drawing--taste--due discrimination of effect--strict observance of the characteristic points in the features of the subject--quick perception of the beautiful, and a knowledge of the art of mixing colors, and blending tints.