Lapas attēli
PDF
ePub

accomplished by the use of the double cylinder machine which, through a most ingenious contrivance of the two cylinders, admits of two sheets being printed at the same time.

Making Ready.—This operation, to which reference has already been made, is probably the most important part of press work, as upon its proper execution largely depends the appearance of the printed sheet. The pressman who is able to “make ready” and prepare the “overlays " for fine illustrated work commands a high salary in any printingoffice where such work is executed.

All forms require more or less “making ready,” for even with the utmost care in casting and finishing plates, it is quite impossible to obtain a number of plates whose face and thickness shall be absolutely true. There will be depressions in the plates in some spots where the plate, in printing, seems scarcely to touch the paper, and corresponding elevations in other places. The first impression taken from a form is, therefore, more or less imperfect, and it is the work of the pressman to overcome these irregularities, either by "overlaying ” or “ underlaying " as may depend upon the character of the press. This process is a very nice one, and it requires no slight amount of judgment upon the part of a pressman to do it effectively. Small pieces of very

thin paper are cut and pasted over the low spots either upon the cylinder, or in the Adams press) underneath the plates. When the impression is too heavy the soft covering of the cylinder is cut away in the proper spot and the pressure equalized throughout the entire form, thus giving an even appearance to all the printed pages.

When, however, wood-cuts appear in the text, the difficulties of “overlaying” are greatly increased, and the expert pressman must possess a good deal of artistic judgment to prepare his form so as to produce effectively in the printed

[graphic]
[ocr errors]
[ocr errors]
[ocr errors]

NEW TYPE ROTARY PERFECTING PRESS.

sheet the design of the artist and engraver. Few people in examining a finely illustrated book, realize the amount of care required in the pressman to produce such work, and they would be surprised to see the difference between the first impression of the form of cuts and a printed sheet after it is properly “made ready.”

“made ready.” Indeed, no matter how artistic the work of both designer and engraver, if the pressman fail to understand his business, the result must invariably prove disastrous.

The pressman may, perhaps, devote two or three days to making the “overlays" to a single form of cuts, building up the “ blacks,” toning down the “half tints,” or cutting away entirely the “high lights” of the design. This is all done in the general way already explained for the plain text, but of course it requires a thousand times more delicate treatment. Paper about the thickness of tissue is used in making these overlays, and a form of cuts may require hundreds of these small pieces of paper,

of every conceivable shape, pasted upon the cylinder before the press can be started for printing.

Hydraulic Pressing. When the sheets come off the press they are allowed to dry for a time, and are then placed between very hard mill-board, and subjected, in an hydraulic press, to an immense pressure. This does away with the roughness existing on the sheet when it comes off the press ; but if a very glossy surface is desired, it becomes necessary to run the printed sheets through hot steel rollers, called a calendering machine. The book is now ready for the bindery.

Book-binding.–When the sheets have been duly pressed in the “hydraulic,” they are passed into the bindery. Here they are taken in hand by the folders-generally girls—for the first operation in binding.

The folding consists of doubling the printed sheet so that the folios lie one upon another with absolute precision.

Any deviation in this accuracy produces a very unsatisfactory-looking book. The number of folds the sheet may require is of course dependent upon the size of the printed sheet, the sheet printed for an octavo book requiring more folds than that for a quarto, and a sixteenmo more than either.

The folded sheets are then piled in consecutive order upon the collator's table, and the collator takes the sheets, one at a time, in their regular order, beginning at the end of the book and finishing with the title sheet.

The folded and collated books having been put through the “mashing machine” to make them as compact as possible, are now taken to the "sawing machine ” and several shallow cuts are made by circular saws in the back of the book. The “ book-sewer” now takes them, and seated before an upright frame, called a “sewing press,” she sews each folded sheet to perpendicular cords on the press, these being so arranged as to fit into the cuts made by the sawing machine. When the frame is filled the books are cut apart and the edges trimmed by a guillotine-cutting machine.

The book is now glued at the back and is then ready for “rounding” and “backing.” The former operation is performed by pounding the volume with a hammer so as to produce the curved appearance to the back of the finished book. After this, the book is placed between two iron clamps, and a heavy roller is worked, backward and forward, over the back. The pressure of this roller forces a small portion of the back over the clamps the entire length of the book, thus producing the joints or grooves in which the cover of the book fits.

The back of the book is now again glued, a piece of muslin, about an inch wider than the back of the book, fastened to it, a piece of very stout paper covers this, and the · book is then ready to be put into the cover or case.

The general system of cloth-binding in England and the United States differs in some essential particulars. In the former the cloth-binding of a book is, as a rule, considered as being merely a temporary covering, to be replaced very shortly by the individual owner's rebinding it in leather or

library” binding to suit his special taste. In consequence of this the English cloth-bound book is generally left with the edges uncut (that the fullest possible margin may be left for the prospective rebinding), while the work of sewing, case-making, and putting into covers is rarely as substantially or durably done as in the United States, where a wellbound cloth book is expected to answer as a permanency for the majority of readers.

The practice of ornamenting the covers of books with elaborate designs stamped in gold, or in colored inks, has grown to an alarming extent, and it cannot be said that such attempts are always an artistic success, the only idea in many cases apparently being to make the volume as showy as possible. Happily, a reaction in this direction is rapidly taking place, and publishers find that for a large portion of standard works issued, a plain, unpretentious cover is much more satisfactory to the buyer who possesses any good judgment in such matters. If it be possible to introduce, either upon the side or back of a volume, some small characteristic design, so much the better, but the elaborate and oftentimes meaningless stamps heretofore placed upon the side of books are certainly not ornamental, and the quicker such are banished from the better class of books the better.

Library Bindings.—Until the last few years but little taste was shown in the United States in what is known among the trade as “extra binding.” Of late, however, much care has been given to this class of work, and there is no department of book-manufacturing showing a greater

« iepriekšējāTurpināt »