A Treatise on Calico Printing, Of Blockmaking.

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.

Previous to what the Writer has to advance on the management of blocks, a word or two addressed to Block-makers cannot be deemed unnecessary, as their inattention in general (if not entirely) to what he observes below, has rendered many prints and grounds of no use; while the fault has been attributed to causes very remote from the real ones. Therefore, if Blockmakers wish for the credit of making firm standing or good working blocks, they should be careful, that, in the first instance, the saces and backs are free from cracks and (hivers, and not tending to a decayed state nb more than being too green, and that of crossed backs the backs are alike in age, texture and seasoning; indeed they should be cut not only from the same plank, but from the same part of the plank, else the resistance of one to the other cannot be reciprocal, and consequently the very purpose for which two backs are joined to gether is directly destroyed; See the observation respecting cross-backed blocks further on.

Block-makers should likewise take care that in   joined faces, the pieces of the face be of the same part of the plank, as a joined face that has one side clear, hard, or strait grained, and the other soft, beachy, curly or knotty, is hardly sit for any purpose; the bad being unfit to go with the good, which is only proper for nice work, and the good part is thrown away if the whole block be used for something coarse, or of little importance; and even a whole-faced one had better not be so, unless the whole face is of the same quality all over; therefore two or more indifferent pieces of veneer had better be put together, as serving for something that is coarse, and the same of two good pieces for a contrary purpose.

Further, if one side of a piece of veneer that is broad enough for a whole face is bad and the ether side good, the face had better be parted, than put on a back whole, it being then in the same predicament as adjoined face, that has one piece good and the other indifferent; in short, a blockmaker had better burn his very indifferent wood, than send it out, unless avowedly sent home as such, and as such ordered, as only fit for common purposes; otherwise sending a num ber of blocks of the above description, gives room to suppose he has not a sufficient quantity of good wood by him, or is too ignorant or negligent of his business, or else incapable of attending it so as to do justice to the orders he may receive.

He should likewise guard against being sus pected of substituting inferior woods (needless to name here) for holly, pear-tree, or whatever else may be ordered, as the discredit will not be escaped, when, in the course of working, their inferior qualities are too evident to cover the deception.

The writer is aware that in some of the in stances just mentioned, much must be left to journeymen, who, too often, are not very solicitous about their master's interest, or reputation. This however does not (with every person) acquit the master of his responsibility; he is applied to, and of course looked to for a proper performance of the orders.

It may therefore be observed, as a hint to Blockmakers, or their men, that among the causes of blocks not standing well, may be their taking part of a plank for a back that has a tendancy to warp one way, and a piece of veneer with a tendancy to warp the other, and glueing them together in such a state. The same may be observed of two cross backs; and likewise of joined faces; in which latter case, the consequence is, one part of the face rising from the back at the edges, and the other rising in the middle, that is, the middle of the joined piece, not the middle of the block.

Another cause is owing to planks, veneers, &c. lying in too hot, or too damp a situation, and are accordingly warped this or that way; hence when made into blocks, and laid in a proper place, they cannot long remain true, but endeavour to recover their pristine state.

Another circumstance not always guarded against, and probably the cause of blocks casting various ways when at work, is the grain of the yeneer running obliquely, sometimes the grain of the back, and sometimes both; in either of these, or similar cases, it is evident the blocks will warp in different directions. A little care would prevent this, by cutting or squaring the pieces either for veneers or backs, directly with the grain; and then, if they cast, it may be jnore expected it will be sideways or endways, {according to the construction of the block) rather than corner-ways, which every one knows is the most, disssicult to remedy. In short, it may safely be said, of prints and grounds that have never been able to do work properly from warping, that the cause has been owing to circumstances not properly attended to by the Blockmaker, in the instances above-mentioned, or in others of which the writer is not competent to speak: However,what he has expatiated on, he here brings to a point which may serve as a kind of me mento to every person who has to do with blocks.

If it be a joined block, see that the pieces are of equal quality as to the face, whether both good, or both indifferent.

If it be a whole face, see that it be nearly the same quality of each side.

See that the grain does not run obliquely, and the same of the back, if a single one.

Of cross-backs nothing can be said but of the outer one, and of that it may be seen whether or not it directly or obliquely answers to the face.

Respecting the seasoning, few caH judge of that at sight; the other circumstances of knotty, beachy, or other kinds of veneers, are what can not always be avoided, as all blocks cannot be equally good, neither is it necessary, as very in different blocks will answer in some instances, where, to use good ones, would be folly and wastefulness.

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