A Treatise on Calico Printing, Of Calendering.

A Treatise on Calico Printing, VOL. I-II
Printed for C. O'Brien, Bookseller, Islington, and fold by Bew, Paternoster-row: Richardson, Royal Exchange: Murray, Fleet-Street: And the Booksellers of Manchester, Glasgow, Dublin, &c.
Respecting this operation, it has been intimated how needful it is to be well performed, and that very much depends on it; it may however be here said, that the chief care is to keep the west as much as possible in the same state as when woven, that is, in respect to the direction of the threads; the omission of which, even when work is folded to go for sale, is evident in many patterns. As, for instance, if a piece be calendered so bad|y, that the threads lay all very obliquely across the table aud the pattern be of a square set: kind, it must be clear that if printed or in such a state, and in she course of the following processes the clothes into, its original state, the work will appear just in the same oblique direction, as the shoot of the cloth did when it lay on the table; and instead of the object being of a square kind, it will appear more like a diamond, which is almost making a disterent pattern of it, and in the instances of small sprigs or other set objects, it must greatly tend to throw them out of shape and their proper distances.

The general inconvenience of calendering in respect to printing is, that the cloth in passing be tween the rollers naturally spreads or expands more or less according to the closeness or eveness of the rolls; hence after printing, in proportion to the quantity of colour used, the cloth gets into its natural state, and is generally found to contract the most lengthways, lo that it is often very difficult to get grounds in, especially if the print be long; and therefore it is deemed needful to stretch it, particularly when work off the grafs is to be performed.

In the operation of printing, which follows, an article is used that much concerns some part of the copper work, which is lamp black, other articles are used in sightning, but none are nearly so pernicious, though all are hurtful in a degree; but something must be used at times for that purpose; the consideration of these articles how ever, come more immediately under the colourmakers department, and of course will be spoken of in another place.

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