Wood Pulp
a preparation of wood used in the manufacture of paper and in other industries. There are two kinds of wood pulp, one known as ground or mechanical, and the other as chemical.
The first is the cheapest and is used chiefly for making newspaper and common wrapping paper stock. In this kind spruce wood is most commonly employed, because it is cheap and gummy, the latter quality being valuable in that it adds much to the tenacity of the material made from the pulp. In the manufacture of ground pulp swiftly revolving emory wheels are worked under water. The spruce logs are pressed against these till reduced to a fine wet sawdust. It has, however, now lost its fiber, and must be mixed with one-fifth chemical wood pulp, so that it will hold together in the form of paper.