On the other hand, mechanical pulp is merely the crushing of wood into pulp with nothing eliminated. These fibers deteriorate in strength and color just as wood does under exposure. Mechanical pulp is used only in the cheapest grades of Book paper, which are classified as Groundwood papers whether they contained a large amount, as in news paper, or a small amount. All Book papers free from Groundwood are classified as free sheets, indicating that they contain only chemical wood pulp or rag, or both. In recent years, the improvement in chemical wood pulps has given us papers of fine strength.

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Page S

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6 X 9'/8

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nches nches nches

nches nches

or nches

nches

nches

nches

Cuts without 32, or 64 up Cuts without or 32 up Cuts without or 24 up Cuts without Cuts without or 32 up Cuts without or 32 up

Cuts without

up

Cuts without

16 up

Cuts without

16 up

Cuts without

Boolclefs on Book Paper waste from 32x44 (128 pages out) when run 4, 8, 16,

waste from 25x38 (64 pages out) when run 4, 8, 16,

waste from 25x38 (48 pages out) when run 4, 6, 12,

waste from 38x50 when run 4, 8, or 16 up

waste from 32x44 (64 pages out) when run 4, 8, 16,

waste from 35x45 (64 pages out) when run 4, 8, 16,

waste from 25x38 (32 pages out) when run 4, 8, or 16 waste from 32x44 (32 pages out) when run 4, 8, or waste from 35x45 (32 pages out) when run 4, 8, or waste from 25x38 (16 pages out) when run 4 or 8 up