The cylinder is the dandy roll, which closes the surface of the paper with slight pressure, and if a water-mark is required the soft pulp is impressed with the design upon the surface of the roll. If the paper is to be "laid" the cylinder will be covered with laid wires, with tying wires at regular intervals, but a wove paper has a woven dandy roll which leaves no mark beyond any watermark that may be on its surface. A dandy roll on which the tying wires run the length of the roll instead of round the circumference is known as a spiral laid dandy roll.
The boxes beneath the wire are suction boxes, open mouth of pumps which suck the remaining water from the paper. The wet end is well named, as for every ton of paper nearly 20,000 gallons of water are used for the dilution of the pulp, so that it may flow evenly and regularly. This water passes through the wire, most of it falling into the save-all and is used again for diluting the pulp.
Passing under the dandy roll and over the last suction box, the wire carries the web of paper through the couch rolls, where the paper is couched or pressed by a felt-covered roll for the same reason as hand-made papers are couched: to consolidate the paper. The wire returns to perform its operations continuously, and the limp paper is carried forward to the press rolls, where it is further pressed by polished rollers, first one side, then the other, to remove the wire and felt marks. Then the paper goes forward to the drying cylinders—massive rolls heated by interior steam; but the heat is so regulated that it is gradually increased, and the speed at which the web of paper travels is arranged so that no undue tension is placed upon the paper, or thinning might result, or the web be broken, and delay caused. The drying section of the
