stamps in two colors. Of course, this necessitates the use of two plates
for each design. This also gives rise to some interesting varieties,
caused by one part of the design being printed upside down. Such
oddities are scarce and are highly valued by philatelists.

When a plate is to be printed from, it is first warmed, then the ink is
applied and rubbed into the lines with a pad. The surface of the plate
is wiped off with a cloth, then with the hand and lastly, polished with
whiting. A sheet of dampened paper is next laid on the plate and the
whole is passed under the roller of a press, which forces the paper into
the lines of the plate, where it takes up the ink. When the plate is
deeply engraved the ink seems to stand up from the surface of the paper
in ridges and some times we find corresponding depressions on the backs
of the stamps. The sheets are then dried, gummed and dried again. They
are now so much curled and wrinkled that they are placed between sheets
of bristol board and subjected to hydraulic pressure of several hundred
tons which effectively straightens them out.

The second process of printing from metallic plates is called
typography. The plates for this process are the exact reverse of those
engraved in _taille douce_. Instead of the design being cut into the
plate, it is on the surface and everything else is cut away. Hence, the
term "surface printing." This form of engraving is also called _épargné_
engraving, because the parts of the plate which bear the design are
_épargné_ (preserved.)

The dies for typographical plates are cut in wood or steel, usually the
former. They are reproduced by two methods, stereotyping and
electrotyping. In the former process casts of the die are taken in
papier maché or plaster of Paris. From these casts other casts are taken