Part 11

After this another impression is taken, and of this sheet an "underlay" is made to further "even up" the form. The low places in the individual plates are carefully marked with crayon or a soft pencil on the impression, and the spots so marked are covered with a piece of thin paper. The printed pages are then cut out a little larger than the type page, and placed under the plates from which they were printed. The plates of the solid pages, which had been substituted for the open pages, are now removed, and the open pages are put back in their places on the form.

Up to this point, all the "making ready" which has been done, is of permanent use in printing all of the forms of the book in question. The work that follows has to be done on each form as it is put on the press.

More thin sheets of paper are now run through the press, the number run through together being one less than were printed for the underlay. These printed sheets are used for "overlays," which are very much like an underlay except that much more care is taken in marking any uneven places. A thinner paper is used to bring up the low places in the plates. An impression of the form is then made on the manila paper sheet which had, as before mentioned, been drawn around the cylinder, and on this printed manila sheet this overlay is pasted, the impression on the manila paper being a guide for the placing of the overlay.

Another overlay is now made in the same way as the first; only it will now be found, if the work has been properly done, that there will be only a few spots to be covered with tissue. After this overlay has been made and the necessary pieces pasted over the first one, a thin sheet of manila is smoothly and tightly drawn around the cylinder, covering completely the thick manila sheet with the pasted overlays on it. The form is then ready to print.

While the feeder, as the man who feeds the paper into the press is called, has been "filling in" the overlay, the pressman should have been getting "register,"--that is, moving the plates so that the headlines and the sides of the plates align properly, and that when both sides of the paper have been printed, the pages will exactly back each other. The ink fountain should also have been so regulated by means of thumb-screws that the right amount of ink will run on the rollers and be distributed evenly over the form. Where too much ink shows on the printed sheet, the thumb-screws on the fountain are tightened a little, to decrease the flow, and where not enough ink shows the thumb-screws are loosened to increase its flow. This process is repeated until the "color" is all right. The grippers, which seize and carry the sheets of paper through the press, the reels, cylinder bands, and many other things have also to be adjusted. These cannot well be described, but have to be learned by actual experience.

The "making ready" and watching the sheets as they come from the press to see that the "color" does not vary, is the skilful part of the process. The feeding can be done by a bright boy after a few weeks' experience, but is now done automatically by machines to a great extent.

While the press was being made ready, another set of men in charge of the paper have taken it out of the cases or bundles, counted out the number of sheets required for each form, piled it on hand trucks, keeping that required for each form separate, and have delivered it to the press. If a machine feeder is used, the paper is piled on the elevator of the feeder, from which it is automatically taken, one sheet at a time, and delivered on endless tapes to gauges on the feed board of the press, thus bringing every sheet in the same position each time. The number of sheets required for the order are printed from one form on one side and then from another form on the other side.

From the preceding it can be seen that to get a press ready may be a matter of hours, while, in the case of ordinary book work, a press generally prints from 1200 to 2000 impressions and more per hour.

The principal difference between making ready a form on a flat-bed perfecting press with two cylinders and on a single-cylinder press is in extra work necessary to obtain correct registering of the plates and in preventing an offset of the fresh ink on the second cylinder. Otherwise, a perfecting press is very much like two cylinder presses joined together. It has two sets of rollers, two ink fountains, two cylinders, two forms, etc., but only one feed board and one delivery. The sheet is fed to one cylinder and printed, taken from this cylinder by the second and printed on the second side, and delivered on the "fly board" ready to go to the shipping department.

The process of making ready forms containing illustrations is practically the same as for plain ones, except that a new underlay is made for each form, and much more care and skill must be used on the cuts themselves. It frequently happens that one or even two days are spent making ready a form of half-tone cuts, before the actual printing, which takes perhaps half a day to do, can be begun.

In most offices, a special "cut overlay" is made for forms with cuts, or illustrations. The cut is placed on a hand press before the form is made up, and proofs on four different thicknesses of paper are made. The heaviest paper is used as a bottom sheet, and the others are pasted on it. Out of the next to the thickest paper of all, the solid blacks are cut and pasted accurately on the same places on the bottom sheet. From the second or next thinner sheet, the medium shades including the solid blacks are cut and pasted on the bottom sheet, thus building up the blacks and strong shadows. From the thinnest sheet of all, the high lights and very light shades are cut, and the rest of the sheet is pasted on the bottom one. In this way the solid blacks and dark shadows on the cut have three thicknesses on the overlay; the next shades two, and the light shades one, where the high lights are cut out altogether. This is the common form of "cut overlay" used in most offices; but there are many other kinds, some being made on metal by chemical action. All kinds are fastened carefully over the impression of the cut made on the heavy manila sheet covering the cylinder, and the cut must not be moved on the form after the overlay has been fastened on the cylinder, or the effect of all the work will be entirely lost.

One of the great troubles which the printer has to contend with, is electricity in the paper. The pressman is unaware of its presence until he lifts a printed sheet from the pile and receives a slight shock, and finds the sheets stick together. In the case of a cut form, the ink is almost sure to be offset, and in printing the second side of the paper the feeder will have to stop frequently to separate the sheets. Much money has been spent and many devices originated to overcome this trouble. Ink manufacturers make a liquid preparation to be applied to the packing. A row of lighted gas-jets placed near the point where the sheet goes on to the "flyboard," a heated steam-pipe, and many other things have been used, but a new device by which electricity is generated and carried into the press, and there neutralizes the electricity in the paper, is the best of them all.

The printed sheets are counted automatically by the press, and as fast as enough accumulate, they are piled on hand trucks and removed to the shipping room. Here they are "jogged up" so that the edges are even and are counted again by hand. If they are to be shipped away, they are tied up in bundles or nailed in cases and marked for shipment. If the bindery is connected with the pressroom, they are simply jogged, counted, and piled on trucks and delivered in this way.

THE PRINTING PRESS

By Otto L. Raabe.

Throughout the stages of development of the book-printing press the chief object has been to lessen the cost of printing. Whether the direct purpose of an improvement has been to increase the working speed of the press, to lessen the necessary operating power, to simplify the mechanism, to strengthen the parts, to lighten the pressman's labor, or to better the quality of printing, the ultimate aim has always been the same. It has been the constant incentive to invention and the standard for judging the adaptability of a press.

It consisted of two upright timbers held together at the top and the bottom by crosspieces of wood and with two intermediate cross-timbers. One of these intermediate cross-timbers supported a wooden or stone "bed" on which the form of type was placed, and through the other passed a large wooden screw, the lower point of which was attached to the centre of a flat, wooden plate, called the "platen." The lower side of the platen was covered with a soft "packing" or "blanket" of cloth. After the type had been inked, a sheet of paper was laid on it. This paper had previously been dampened so that it would take a better impression of the type. The screw was then turned down until the platen pressed the paper against the inked type, and produced a printed sheet.

The form of type was incased in a frame called a "coffin." These coffins and the type within them were very heavy, but they had to be lifted in and out of the press by hand. After each impression the platen was screwed upward so that the sheet of paper which had been printed could be removed and hung up to dry.

This simple form of press continued in use without material change until the early part of the seventeenth century. The first improvements on it came about 1620, and consisted of a device for rolling in and out the wooden or stone bed on which the type rested instead of lifting it by hand, of a new form of iron hand-lever for turning the screw, and of an iron screw in place of the wooden one. These were the inventions of William Janson Blaeuw, a printer of Amsterdam. Blaeuw's press was introduced into England and used there as well as on the continent. It was substantially the same press as that on which Benjamin Franklin worked when in London in 1735.

After this first type of printing press had been in use for three and a half centuries, a much-improved form was invented by the Earl of Stanhope in 1798. The frame of his press was made of iron, cast in one piece; the bed, the impression plate, or "platen," and the other large parts were also of cast iron, while the working parts were of iron, steel, or brass. The iron impression screw was retained, but connected to it was a combination of levers whereby its power was greatly increased. This enabled the printing of larger forms and the use of a thinner and harder "packing," or "tympan," between the platen and the sheet of paper to be printed, resulting in a sharper and clearer impression. Much less exertion was required to work the lever, and at first, on this account, a printer, who was accustomed to use all his physical force on the old screw press, found it difficult to work on the new one.

This improved style of press was received with so much favor by printers that several persons took up its manufacture, and competition soon reduced its cost and brought it into general use for printing newspapers as well as books. The process of printing remained about the same as in the earlier presses. Two men were required to work it. One spread the ink on a wooden block, rolling over it with two leather-covered balls, about six inches in diameter, stuffed with wool or horsehair, and fastened to round wooden handles. Holding one of these inking balls in each hand, he then rolled one upon the other to distribute the ink evenly over both of them, and applied the ink to the face of the type by rocking the balls over it until the entire form was inked. While this was being done, the other man was placing the sheet of paper on the "tympan." This was a light frame, in two parts, really forming two frames, one inside the other, and both covered with parchment. There was a woollen or felt blanket between them, and the two frames were held together by hooks. The outer frame was hinged at its lower end to the outer end of the bed of the press, and when ready to receive the paper, it stood in a nearly upright position at about right angles to the bed. On the frame were two or four pins, upon which the sheet of paper was impaled.

Attached to the upper end of the inner frame by hinges was a thin and narrow frame, called the "frisket," of the same length and width as the inner tympan frame. This frisket was covered with strong paper in which were openings, cut a little larger than the size of the pages of the type-form. When the sheets of paper had been placed upon the tympan frame, the frisket was folded down upon it, and the two were then turned down over the form of type. The bed was then "run in" under the platen by means of a crank at the side of the press, and the platen was screwed down to make the impression. After the impression had been taken, the platen was screwed up, the bed "run out," the tympan frame and frisket lifted, and the printed sheet taken off.

The introduction of this Stanhope press gave a great impetus to the development of the printing press in other countries as well as in England, and many varieties were devised during the thirty years following. Although as early as 1811 Koenig had made a cylinder press which had proved fairly successful, the better grades of printing could be obtained only by the flat pressure of the hand-presses. In some of these hand presses, the platen, or upper impression plate, was moved into position over the bed and remained stationary while the bed with the type-form upon it was forced upward to make the impression. In others, the platen was hinged to the bed, but in all of them the mechanism was complicated.

The "Columbian" press, devised by George Clymer, of Philadelphia, in 1816, gained considerable distinction both in this country and in England, where it was introduced in 1818. It differed from the Stanhope in that the screw was dispensed with, the platen being depressed by a combination of levers and lifted by the aid of a weighted balance-lever.

The reduction of the hand-lever movement to its simplest and most powerful form is now seen in the Washington hand press, devised by Samuel Rust, of New York, in 1827. His patent was later purchased by R. Hoe & Co., who made nearly seven thousand of these presses in different sizes and still make many of a greatly strengthened pattern for taking fine proofs from photo-engraved plates. Some of these presses made before 1850 are still in use, and occasionally one hears of a Washington hand press being used for printing upon handmade paper an edition of a small and limited number of copies of a book. Of all the hand presses, this is the only one that has survived to the present day.

With the introduction of other means for applying power than the hand-lever, a distinction came to be drawn between printing presses and printing machines. The term "machine" might perhaps be more appropriately used for the huge printing presses of the present day, yet, as the first essential is the impression power, all other features being subordinate, the term "press" is still the proper one to apply, even to the greatest combination of printing units yet devised.

The "bed and platen" system of printing as first used in hand presses occupies such an important place in the history of the book-printing press that a further description of its career is necessary.

In December, 1806, Friedrich Koenig, a Saxon, who later gave to the world the first practical cylinder press, went from Germany to England to seek assistance in carrying out his plans for the construction of a greatly improved printing press, having failed in his efforts in his own country and in Russia. He succeeded in enlisting the support of Thomas Bensley, a London printer, and constructed a press in which all the operations but laying on and taking off of the sheet were performed mechanically.