is speedily destroyed, but the paper is not thereby fully whitened.
A paler yellow remains as a residual tint, and this on
continued exposure to the light, slowly darkens to brown.
Exposed to the spectrum, the paper is first reduced nearly
to whiteness in the region of the blue and violet rays.
More slowly, an insulated solar image is whitened in the less
refrangible portion of the red. Continue the exposure,
and a brown impression begins to be percieved in the midst
of the white streak, which darkens slowly over the region
between the lower blue and extreme violet rays.

THE RED POPPY yields a very beautiful red color, which is entirely
destroyed by light. When perfectly dried on paper the color becomes blue.
This blue color is speedily discharged by exposure to the sun's rays,
and papers prepared with it afford very interesting photographs.--
Future experiments will undoubtedly more fully develope the photogenic
properties of flowers, and practically apply them.

Certain precautions are necessary in extracting the coloring matter
of flowers. The petals of fresh flowers, carefully selected,
are crushed to a pulp in a mortar, either alone or with the addition
of a litte alcohol, and the juice expressed by squeezing
the pulp in a clean linen or cotton cloth. It is then to be
spread upon paper with a flat brush, and dried in the air.
If alcohol be not added, it must be applied immediately,
as the air changes or destroys the color instantly.

Most flowers give out their coloring matter to alcohol or water--
but the former is found to weaken, and in some cases to discharge
altogether these colors; but they are in most cases restored in drying.