Page:Paper and Its Uses.djvu/27

Rh vatman—stands is kept supplied with pulp, diluted to a regular consistency, kept in motion by an agitator, and a constant temperature is maintained. The mould used is a wooden frame, strengthened by ribs across its width, and a wire top of laid or woven wire. In the case of laid papers the wires are laid side by side, tying wires about an inch apart are superimposed, and fastened to the laid wires by very fine brass wire. These wires make an indelible impression upon all paper made upon the mould, and distinguish laid from wove papers, the latter being made upon a woven wire mould. Watermarks are the results of designs in reverse fastened to the mould, the design being formed with wire upon the mould, or else an electrotyped mark is soldered to the mould.

Watermarks may be simply small designs or lettering, or they may take the form of elaborate pictorial designs, but their purpose is to add distinction to the paper, and in some cases to prevent forgery of valuable notes or documents. Upon the mould is laid an open frame, known as the deckle, which serves to confine the pulp to the mould. For all papers two moulds are used in order to continue the cycle of operations uninterruptedly.

The vatman takes a mould, places the deckle upon it, dips the mould into the vat of diluted pulp, and lifts just the quantity of pulp necessary for the weight of paper being made. A slight shake is given to the