re scattered through it. The paper called
granite or silurian has a quantity of colored threads mixed with the
pulp. In Switzerland blue and red threads were used, giving the paper a
slightly grayish tone. In Servia only red threads were used but in
sufficient quantity to make the paper appear a faint rose color.

Manila is a coarse buff paper made from manila fibre. It is generally
used for newspaper wrappers.

It will scarcely be necessary to say that paper is found in a great
variety of colors and that such colored paper has frequently been used
for stamps.

We cannot consider paper without treating of watermarks, since they are
made in the process of paper making and constitute an important feature
of stamp paper. Watermarks are designs impressed in the paper pulp. The
paper is slightly thinner in the lines of these designs and appears
lighter when held to the light. Of course you are all familiar with this
appearance from having noticed the watermarks in note paper. On rare
occasions the watermark is a thickening of the paper instead of a
thinning. In such a case the watermark appears more opaque than the
paper. Watermarks in paper used for stamps are, of course, intended as a
security against counterfeiting.

[Illustration: Watermark U.S.P. (mirrored letters)]

There are a great variety of watermarks; words, letters, figures,
heraldic devices, etc., etc. Sometimes the design covers the whole sheet
and at other times several stamps, but usually there is a separate
watermark for each stamp. The current stamps of the United States are
watermarked with the letters "U. S. P. S.", United States Postal
Service. This is so set up that the letters read in sequence from any
point and in any direction. At one time several of the British colonies
in Australia employed paper watermarked with a figure or word of the
value of the stamp intended to be printed on it. It can readily be
understood that these would sometimes get mixed and result in more of
those oddities in which philatelists delight.

[Illustration: Watermark, Crown with letters CC]

[Illustration: Watermark, Crown with letters CA]

[Illustration: Watermarks, Cross and Orb, Anchor, Elephant Head,
Pine-Apple, Castle]

[Illustration: Water Marks, Post Horn, Turtle, Geneva Cross]

Here are some well-known watermarks. The letters CC under the Crown
stand for "Crown Colonies." This was extensively used on stamps of the
British Colonies. It has been replaced b