There are several different ways of making these. Obtain some
Balmain's luminous paint, and coat a piece of cardboard with it. Place
this in the dark until it is no longer luminous; place this behind a
glass transparency and expose to light, either daylight or, if at
night-time, burn a small piece of magnesium wire. Return to the dark,
remove the transparency, and a luminous photograph is obtained on the
prepared card. A simple plan is to merely expose a piece of the
prepared cardboard to the light and place it behind a transparency;
then retire to a darkened room. The luminous paint, showing through
it, will have a very pretty effect. If no glass transparency is at
hand, a silver print can be used, if previously oiled and rendered
translucent by vaseline or any other means.