This stand will be large enough to hold six slides at once, and enables the light to shine right through them. A sheet of white paper should be placed underneath to throw the light up.
Should the light be too strong it can easily be modified by spreading a sheet of thin, white tissue-paper between the glass and the slides.
Of course daylight is best to work by, but I find you can get on very nicely with an ordinary oil lamp, if placed at a convenient distance from the stand.
An ordinary paintbox will contain twelve colors—namely, two blues, neutral, crimson, brown, yellow, scarlet, burnt sienna, orange, two greens and black, all but the last being quite transparent. These will be found sufficient for ordinary work, as they can be greatly varied by judicious mixing.
First of all the skies should be painted in on all twelve slides. As long as you do not go over the outlines, great care need not be taken about laying the color on evenly.
Now cut off a small piece of clean washleather, which has an even, smooth surface. Let the color become nearly dry, then proceed to dab it all over with the washleather, held on the end of the finger, breathing on the slide when necessary, in order to keep it sufficiently moist.
This process must be continued carefully until the whole painted surface is perfectly even and shows no mark of the brush, and only sufficient paint must be left on to give a blue tint.
You must always remember that if too darkly painted the pictures will be too opaque. Clouds can be put in nicely also with the bit of washleather, but extra work of this sort is hardly worth while.
Then proceed to tint the other portions of the pictures with suitable colors, doing one color at a time right through the set of slides, but after applying each color, immediately
dab with the washleather, to render the color even and light.