The third side is pinned down by first fixing a pin in the centre, then in the centre of the halves to right and left, then proceeding with the smaller divisions in the same fashion. The material is pulled far enough to form a straight line (Fig. 127). The last side is well stretched and pinned down as just described. In this way a surface not only entirely free from wrinkles and creases is produced, but the texture of the material will run straight.

In mounting upon cloth, special care must be taken that the paper is perfectly limp and flexible; but this must not be due to its having been too thickly coated with paste.
Large wall maps made up of many pieces must be very carefully damped and must be allowed to lie damp a long time. Attention must be given to the colors, which are apt to run, and also to the proper fitting of the various pieces, as these have often been stretched in various ways in the lithographic press, or through irregular drying have taken unequal sizes. Damping and pasting must be repeated to help to remedy this until the whole fits together perfectly.

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