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72 shown above. The fact that lithographers prefer papers cut with the cross direction coincident with the narrower dimension of the sheet is sufficient proof that it is not the machine tension that is dreaded in register work.

Writing and most printing papers, which may or may not be printed in more than one colour, are frequently cut two ways of the webs, that is, a 30 by 40 inch paper, if cut from a web of 70 inches net width, is cut without waste by cutting sheets 30 inches wide from one part and 40-inch sheets from the remainder of the reel. All papers on which register work is to be printed must be cut with the same machine direction. In ordering paper which is not generally used for work in several printings, the printer should be careful to point out the purpose for which it is intended, and ask that the instruction shall, if necessary, be passed on to the papermaker.

Cockling in paper is caused by the paper being drier or damper than the atmosphere, and shows that there is unequal expansion of the sheets, and exposure as detailed above should be tried as a remedy. Cardboards which are cockled may or may not improve upon exposure to the atmosphere. The thicker the cardboard the less likely it is to alter its shape. Usually the fault will have arisen through severe drying under tension, stretching the boards, and drying while unequally stretched. The cockling and wavy edges of boards are frequently found to be permanent faults.

Wavy edges to paper, if at the feed edge, will frequently cause bad creasing, from which damage to the printing surface may result. Creasing from defects of the machine, make-ready, or printing surface must not be visited upon the papermaker. If the paper will not respond to exposure to air, feeding the narrow way