To use the enamel toning bath, proceed as follows:- Pour some out into a clean dish to the depth of about 1/2 in., stand near to this a large dish filled to the depth of 1 in. with clean water, and also a small dish with pieces of glass in it under water; the glasses may be about quarter - plate size, or such as will be found most convenient. Now take up one of these glasses, and slip it under the film containing a transparency to be toned, gently raise the glass to the surface (at the same time manipulating the film with a camel's hair brush, held in the light hand) in such a manner that when the glass and film on it are lifted out of the water, there will be an edge of film (say) 1/4 in. wide lapping over one edge of the glass. The action of the water, as the plate is taken out, will wash this piece or edge of film round to the back of the plate, and, by so doing, will fix the transparency on the glass in a very satisfactory manner. If care be taken that the edge where the film laps over is kept uppermost, or highest, a considerable stream of water may be poured on the film without any danger of it slipping. Having got the film on the glass, it should be rinsed under the tap in the manner just suggested, and the film may then immediately be transferred to the toning bath.

To do this, turn the glass over so that the body of the film is underneath, lower it gently under the surface of the solution, and with a brush disengage the lap of film where it had turned the edge of the plate, now, of course, uppermost. As soon as this is done, the film will move off into the solution free of glass, which can then be removed. When the film has floated free for about a minute, turn it over with the brush, and note carefully if the deepest shadows are toned through, so as to give one uniform tint to the whole film. Turn the film over and over, and move it about till this is effected, and as soon as it is so, remove it from the bath by the same piece of glass, used in the same manner- i.e. securing the film by making a little piece of it lap over to the back along one edge of the glass. Let the film drain a few moments, and then transfer it to the large dish of clean water. As soon as it is free of the glass in this dish, gently agitate the water with a brush, so as to wash away the toning solution still adherent to the film.

There is a strong objection at this stage to washing the film under a tap dish - washing is far preferable, and as little of that as possible should be employed. As each print is toned in succession, it is placed in the same large dish of water. Use one that will take a half - sheet of paper. When all are finished so far, change them one by - one into another dish of water, taking up each film with the glass as before described. This is all the washing they are to have. Now proceed to mount them on the tablets. First of all, pour back the toning bath and put away the dish it was used in, then set before you on the table 2 dishes, one filled about 1/2 in. deep with ammonia solution, and the other about the same depth with clean water.

Formula for the ammonia solution: -

Ammonia solution at 880° . 6 dr.

Water . . 12 oz.

(This must be kept well corked.)

1/2 oz. of this mixture, diluted with 1 pint of water, makes the bath into which the films are to be plunged.

Get a chair and sit down to the work, as it is far easier to manipulate the films if both arms can rest on the table. Take off your watch and place it before you, so that you can see it as you work. Place in the dish of clean water a clean glass, and on that an enamel tablet, carefully washed previously. Take another clean glass, and with it remove one of the toned films from the dish in which it was washed, and plunge the same into the ammonia bath. As the film enters the solution,, take the time by the second - hand of the watch, and withdraw the film when it has been in 20 seconds; plunge it as rapidly as possible into the water where the tablet is, disengage the glass, and slightly agitate the water in the dish, to give the film a sort of wash. Now take up, with the left hand, the piece of glass on which the tablet rests, and raise it about halfway to the surface; then, manipulating with the brush, held in the right hand, bring the film to its proper position over the tablet. By raising the latter very gradually, the film can be laid in its place in this way with the utmost certainty. As soon as the glass is fairly out of the water, place it with one edge raised a little, so as to drain.

If the glass is placed at too steep an angle, there is danger that the tablet will slip out, or, at any rate, get disarranged.

It is proper to note in this place, that the tablets, being curved, the films will not lie fiat without the exercise of a little care on the part of the operator. Care must be taken to avoid the formation o. one ridge or two around the edges of the tablet, but the spare film should be made to lie as nearly as possible equally in all directions. If this is done with care, no puckers or laps will be found in the film when it is completed in the next stage of the proceedings. When the films have got almost surface - dry, the tablets are removed from the glass plates on which they were lifted from the water. To do this, place the plate level, and with a sharp - pointed stick tear away the useless film around the edges of the tablet, slip a thin knife under the tablet, lift it off the glass on to a sheet of blotting - paper, and at once cover it with a large bell jar or other glass vessel, to protect it from dust and accident.

The picture is now ready for burning, and it should at this stage look like a finished enamel, and be as perfect in every respect, in the matter of light and shade and tone, etc, only it will be of a bluer shade of colour than the finished result; but it ought to have the same relative shade of colour now as it is to have in the completed article. The tablet may be burned at once, or left many days, or even weeks, without change.