The adjustment of the margin is the next process. Although type can be printed from any quarter of the bed, it will be found most judicious to lay all forms close to the back part of the bed, and equidistant between the bearers. This will secure a good impression, give a fair average margin to every form, and allow the full use of the bed for a large form, without resetting the cylinder. The bed and cylinder travel together, and the grippers, which bring down the sheet to the form, should barely lap over the back part of the bed. So long as the toothed cylinder wheel, and the short toothed rack on the side of the bed, remain undisturbed, the grippers will always pass over the bed in exactly the same place. When the grippers are in this position, (slightly lapping over the back of the bed,) take measurement of the distance between the back edge of the bed and the point of one of the nearest grippers. With a piece of reglet cut a gauge exactly corresponding to this measurement. Let no form be laid upon the press until the distance between the type and the edge of the chase tallies with the gauge. This will prevent the grippers from closing on the form and crushing the type. If the chase will not admit of so wide a margin, or if an extra margin is wanted on the sheet, put a piece of furniture of the extra width behind the chase: the margin can thus be increased or diminished at pleasure. A book form may be locked up in a chase so large, with the type so far from the edge of the chase, that the grippers will bring down the sheet in such a position that it will be printed with the margin all on one side. To remedy this, the cylinder must be reset. Proceed thus. Remove the screw and washer, and draw the intermediate wheel out of gear, loosen screws in the gauge rack, then turn the cylinder to the point required, connect the intermediate wheel, adjust the gauge rack, and screw up tight. The press having been adjusted, next examine the form to be printed. Not only see that it is gauged correctly, but also see that it is not locked up too tightly,—that chase, quoins, letter, and furniture are all level, and lie flat upon the bed. If the form springs, the quoins must be slackened; if this loosens the type too much, the justification should be amended. Make clean the type by rubbing it over with a dry brush. The rollers are often made foul and the colour of the ink changed by dust and particles of dirt clinging to the type.