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Monotype justification is effected as follows: an ingenious registering device waits, as it were, on all the movements of the operator, with the result that when he has approached as close to the end of the line as he dare go, he has merely to glance at a cylindrical dial in front of him. The pointer on this dial signifies to him which of the "justifying keys" he must depress. He touches them in accordance therewith, and the line is justified, or rather it will be justified when, as will be seen later on, the casting machine takes up its part of the work. That is the outward manifestation; it remains to be seen in what manner the machine accomplishes its task. Firstly, the machine automatically notes the exact width of the space left over at the line's end; then, also automatically, it records the number of spaces between the words already set which form the incompleted line; finally, it divides the residuary space into as many parts as there are word-spaces, and allots to each of these one of the parts. Thus if there is one-tenth of an inch to spare at the end of the line and ten word-spaces, then one-hundredth of an inch added to each of these spaces will justify the line with mathematical accuracy. But the machine will do something more wonderful than this. It will separately justify separate parts of the same line. The utility of this is comprehended when it is pointed out that when the "copy" to be set consists of what is technically termed "tabular" matter, the various columns of figures or so forth composing it are not composed vertically but horizontally and so each section must of necessity be justified separately.
Should the compositor be required to "over-run illustrations," as the term goes, in other words to leave a space in which the "block" for a cut may be inserted, so that it may have type all around it or on one side of it only, the machine offers no difficulty at all. All that the operator has to do in this case is to carry the composition of each line as far as necessary and then complete it with a row of "quads," or spaces. Thus, when the composition is cast by the casting-machine the space into which the block is to fit is occupied by a square of "quads." These have only to be lifted out, the block inserted, and the trick is done.
We will then imagine that the operator has finished his task. Of the bank of two hundred and twenty-five keys in front of him (the equivalent of a full "font" of type, with figures, italics, and symbols complete), he has depressed in turn those necessary to spell out the words of his copy, he has put a space between the words he has justified in accordance with the dictates of the justifying dial, has arranged the spaces for the insertion of blocks or illustrations, and as the result of his labors he has merely a roll of perforated paper not unlike that which operates the now familiar pianola or piano-player. Yet this roll of paper is the informing spirit, as it were, of the machine. Its production is the only portion of the work of the monotype for which a human directing agency is necessary, every other function being purely automatic.
The roll of perforated ribbon is lifted off the keyboard and put in place on the casting-and setting-machine. As it is swiftly unwound it delivers to the casting-machine the message with which the operator has charged it. Through the perforations he has made compressed air is forced. Now, as has been explained, the holes correspond to the characters or typographic symbols of the "copy," and the jet of air forced through them sets in motion the machinery, which controls what is known as the "matrix-case," a rectangular metal frame about five inches square, which contains two hundred and twenty-five matrices, or little blocks of hardened copper, each one of which is a mould corresponding to a character on the keyboard. This frame is mounted horizontally on a slide, which by an ingenious mechanical movement brings any one of the two hundred and twenty-five matrices over what is termed the mould. The particular matrix thus placed in position is determined by those particular holes punched in the paper ribbon at the keyboard, through which the compressed air is at that precise moment being forced.
The mould referred to is closed by the matrix, a jet of molten metal is forced in, and in an instant the type is cast, its face being formed by the matrix, its body or shank by the mould. The cast type is ejected and takes its place in the galley, to be followed by another and that by yet others in their regular rotation. It must, however, be pointed out that the composition emerges from the machine hind part foremost and upside down as it were. This enables the justification holes, which were originally punched at the end and not at the beginning of each line, to direct the proper casting of the spaces in the lines to which they correspond.
It will be seen, therefore, that the casting portion of the monotype machine is actually automatic. It performs all its operations without human assistance or direction. Occasionally it will stop of its own accord and refuse to work, but this merely means that it has found something amiss with the perforated instructions, a mistake as to the length of a line or so forth, and it refuses to continue until the workman in charge of it puts the error right, then it starts on again and continues on its even course, casting letters and spaces and punctuation marks, and arranging them first in words, then in lines, next in paragraphs, and finally in a column on the galley.
The casting-machine works at so high a rate of speed (casting from one hundred and forty to one hundred and fifty characters per minute) that it can in its output keep well ahead of the operator on the keyboard. This, however, so far from being an inconvenience or leading to any loss of time, is an advantage, for four casting-machines, which can easily be looked after by one man and a boy, can cope with the work of five keyboard operators, or if all are engaged on the same character of composition two casters can attend to the output of three keyboards. This suggests a reference to the facilities offered by the machine for the production of matter composed in various faces of type. The machine casts practically all sizes in general use from five-point, or "pearl," to fourteen point, or "English." Owing to the number of characters included in the matrix-case, it can at the same time set upper and lower case, small capitals, and upper and lower case italics, or any similar combination of two or even three different faced alphabets. To change from one complete set of matrices to another is a simple operation, performed in about a minute of time, while the changing of mould, which insures a corresponding change in the size of the "body" of the type, takes about ten minutes.
To return, however, to the perforated roll of paper, which it must be imagined has passed entirely through the casting-machine and has been automatically re-rolled. Its present function has come to an end, and it is now lifted out of its position on the machine and placed away for future reference in a drawer or cabinet. This is a by no means unimportant feature of the Monotype, for it is thus no longer necessary to preserve the heavy, cumbrous, and expensive "plates" of a book in anticipation of a second edition being called for at some future time. As a matter of fact, indeed, "plates," or electrotypes of monotyped matter, are by no means a necessity. Many thousand impressions can with safety be printed from the types themselves, and these latter at the conclusion of the job can be remelted and new type cast from the resultant metal. The paper rolls, occupying but a few square inches of space, can be kept, and when the time arrives may be passed through the casting-machine again, to supply a new printing surface identical in every respect with the original.
But the galley of monotyped composition has been waiting during this digression. It is lifted off the machine by the attendant and a rough proof pulled, which is corrected by the proof-reader. The advantage of the individual types is then apparent, for the composition is corrected and otherwise handled precisely as would be the case had the matter been set entirely by hand. Indeed, the operation consumes even less time, for the discarded characters, instead of being placed back carefully in their proper compartments in the case for future use, are merely thrown aside by the corrector, to find their way eventually into the melting pot. It may be added, however, that the Monotype itself furnishes the types used in the correction of its matter—"sorts," as they are termed by the printer. These are cast by the machine during the times when it is not employed upon more important work.
Indeed, an attachment has recently been added to the machine, whereby its use as a type-caster is still further extended. As has been mentioned, the machine casts and composes type of any sized face, from five to fourteen point. With, however, the attachment referred to, it can now cast for the use of the hand compositor complete fonts of type up to and including thirty-six point in size, so that an entire book, title-page included, nowadays often owes its typographical "dress" to the ingenious machine known as "The Lanston Monotype."
PROOF-READING
By George L. Miller.
When part of a book has been set up in type, in what is called "galley form," an impression is taken, technically known as "first proof," and this proof is handed to the proof-reader. This long-suffering individual lives in a chronic state of warfare with the compositors on the one hand and the author on the other. His first duty is to see that the proof agrees with the author's manuscript, that nothing has been omitted, and nothing inserted that is not in the copy. He must see, further, that the spelling, punctuation, capitalization, grammar, and so forth, are correct, and the book set according to the "style" ordered. He first of all, therefore, compares the proof with the manuscript, or an assistant reads the manuscript aloud, the proof-reader listening intently for any variation from the proof before him and marking any errors he may find.
Now this seems easy enough, and if every author prepared his copy carefully, so that there could be no possible mistake as to his meaning, nothing would be easier; but in practice a number of questions arise which would never be thought of by an outsider. On a new work being put in hand, some half-dozen compositors are given a few sheets of copy apiece, and if the proof-reader happens to be readily accessible he is bombarded within the first half-hour or so with, "How am I to spell centre?" "Has travelling one or two l's?" "Shall I capitalize the word State?" "Shall I spell out two hundred?" "Do you want ships' names in Italic?" and so on and so on. As to punctuation, every compositor thinks he knows better than proof-reader and author combined and follows his own sweet will. As every error on the first proof must be corrected by the compositor at his own expense, here arises the cause of war mentioned in our opening paragraph.
Much has been written about printers' errors and the mistakes of "the intelligent compositor." Aside from those caused by illegible manuscript, mistakes arise from faulty "distribution," that is to say, the type has been thrown into the wrong boxes. Thus we get c for e, h for n, y for p, etc., these boxes being contiguous and the letters of the same thickness; if, for instance, the compositor picked up u instead of t the difference in thickness would at once be noticed by him and the mistake rectified. Then letters are sometimes set upside down and we find letters of a different "face" which have got into the case by mistake. In type set on machine, errors arise from striking adjacent keys, or some matrix will stick in the channel and make its appearance later, sometimes even in the next line. But the chief source of error is illegible or carelessly prepared manuscript, and to the author's slips of the pen must be added in these days the slips of the typewriter.
It is quite possible for a man to be an expert in astronomy, medicine, or natural history and yet have hazy ideas on spelling and punctuation. "When in doubt use a dash" is an old standing joke, but some authors use dashes all the time, making them do duty for commas, semicolons, and periods. They will write indifferently 4 or four and frequently their capital a's c's, m's, and n's cannot be distinguished from the small letters. They will commence a story telling that the "Captain" did so and so, and lo, on the next page the "captain" sinks into a common noun; and so with "Father," "mother," "Aunt," "uncle," etc. Just see what the story would look like if set according to copy!
Now the proof-reader is expected to rectify all this, thereby drawing on his head the wrath of the compositor, who says "he followed the copy," and occasionally incurring the wrath of the author as well for departing therefrom. Sometimes instructions are given that the author's spelling, punctuation, etc., are to be carefully followed, when of course no question can arise; and the proof-reader will query on the proof submitted to the author anything which does not seem to him to be correct.
The great newspapers and magazines have what they call a "style sheet" for the guidance of their compositors and proof-readers and insist on its being faithfully followed. Only by this means could uniformity in the appearance of the paper be secured. In this style sheet careful and minute directions are given for the use of capital letters, the use of Italic, spelling out of numbers, compound words, etc. In the Government printing-office in Washington they have a style book of some two hundred pages. Some book printing-offices have what they call "the style of the office," which will be followed if no instructions are received from the author to the contrary, while some publishing houses with connections in England insist on English spelling being followed in all their books, as books with American spelling will not sell over there.
Here is an outline of an "office style":—
"Spell and divide words according to Webster's dictionary.
"Capitalize President and all Secretaries of State, Senator, Congressman, Governor, Government (of U.S. or other country), King, Emperor, Republican (and all political parties), all pronouns relating to the Deity, Legislature, State, Nation, Street, Avenue, (Hudson) River.
"Use small capitals for B.C., A.D., A.M., and P.M.
"Use Italics for names of ships, names of characters in plays, names of newspapers and magazines, and all foreign words.
"Use quotation marks for names of books.
"Spell out all numbers under 100.
"Compound co-operate, to-day, to-morrow.
"Use period after per cent., and Roman numerals I. VI., etc.
"Bible references in this style: 2 Kings vii. 29.
"All poetical quotations to be in smaller type than text."
Now, some authors will not accept the above style and insist on one entirely different. Many will accept Webster's spelling but draw the line at theater, which they want spelt theatre, and balk at skillfully and skillful or installment. They will order spelling according to the Standard Dictionary, yet will not accept sulfur, rime, or worshiping. One man wants all his numbers in figures, and another does not like compound words. Still another abhors dashes or colons, or quotation marks, and yet another will not have Italic type used in his work.
So it frequently happens that a proof-reader will have passing through his hands three or four books in entirely different styles, each of which he must bear in mind and conform to if he would avoid trouble. But whatever style be adopted, it is essential that it be strictly adhered to throughout the work; therefore in large printing-offices where there are many proof-readers care is always taken that, however many compositors may be engaged in setting up the work, the same reader handles it from start to finish.
If the proof-reader finds any passages whose meaning is not clear, or sentences of faulty construction, he will call the author's attention thereto. He will also call attention to Biblical or poetical quotations which he may know to be incorrect. Many authors will quote Scripture or poetry from memory, which is found to vary in many respects from the original on verification. And then they complain because "the printer did not set it up right,"—when they are charged for corrections. But why should the compositor bear the expense of correction—or the master-printer for that matter—when the copy was clearly wrong in the first instance? A moment's thought will show the injustice of such a procedure.
From what we have said may be seen the importance of the reading of "first proof." Many offices have the proofs read twice, first without referring to the copy, when the more glaring errors may be corrected at leisure, and then again carefully read by copy. The proofs are then returned to the compositors for correction, each man correcting the portion he set up.
A second proof is now taken which is put in the hands of another proof-reader (or "reviser") for revision. His business is to see that the corrections of the first reader have all been duly made. Should he find any palpable errors that have been overlooked by the first reader, he will call his attention thereto and on approval mark them. It may be necessary to return the proofs again to the compositors for correction, and even a third time. When found to be what is called "clean," they are sent to the author (usually in duplicate) along with the copy.
And now the author sees himself in print, perhaps for the first time. He will notice that his work presents a different appearance from what it did in manuscript. Here and there a passage can be improved, a phrase polished, an idea amplified—the same man will think differently at different times; and lo, here, the stupid printer has made him speak of a marine landscape when he wrote Maine landscape! (That proof-reader must be disciplined.) And here a sentence has been left out which he wrote on the back of his copy and has been skipped by compositor, copy-holder, proof-reader, and reviser alike! Then the queries of the proof-reader must be answered, and a few commas here and there would improve things,—and so he proceeds to mark up his proofs, for all of which corrections he has to pay at so much per hour—second cause of war.
The proofs are now returned to the printer and corrected, and a revise (after passing through the proof-reader's hands) sent to the author, which process may be repeated ad infinitum, until the author gives the order to make up into pages.
The type is now handed over to the "make-up," and inasmuch as his work must be carefully revised by the proof-reader, we may describe it here. Having first of all made a gauge showing the size of the page—supposing the page to be seven inches deep, he will cut a notch in a thin piece of wood showing that size—he must "cast off" or estimate how the pages are going to "break." There must not be any short lines, or "widows" as the printers call them,—that is, the concluding lines of paragraphs which are not full length,—at the heads of pages. The first line of a paragraph should not appear at the bottom of a page (but this rule is more honored in the breach than the observance), and the concluding page of a chapter should not be less than one-quarter page in length. These difficulties are avoided by "saving" a line here and there,—that is, where the last line of a paragraph consists of only one or two words, in squeezing them into the line above, or by "making" lines, which is accomplished by spreading long lines out and driving one or two words over. Any line containing one word only at the end of a paragraph ought to overlap the indention of the first line of the next paragraph. Such a word as "is" or "it" will not do so and should be turned back to the line above. Then again, where cuts or illustrations are inserted in the text a page will sometimes break in the middle of a cut, which, as Euclid says, is impossible, therefore the cut must be moved, sometimes necessitating slight alterations in the text, e.g. "The following illustration" must be altered to "The illustration on the next page," or "The illustration above," as the case may be. And here we may remark that all cuts or illustrations should be made and furnished to the printer in time to be inserted in the first proof. The writer calls to mind an instance where the cuts arrived after the whole book had been made up into pages, necessitating a re-make-up at considerable expense.
Proofs of the pages being furnished to the proof-reader, he first of all compares them with the author's last galley proof to see that nothing has been omitted (frequently lines fall off the ends of galleys), that they are in due sequence and "join up," and that the author's last corrections have been made. He then sees to the pagination, the running heads at top of each page, and sees that the foot-notes have been inserted in the pages where they belong and verifies the reference marks. The author will probably have used the * [symbol: dagger][symbol: double-dagger] Sec. and they will have been so set up, as they appeared on each page of the original manuscript. But when in type and made up into pages they will probably fall differently, the note bearing the Sec. mark may come on the following page and of course must be altered to an *, a corresponding change being made in the text. A much better plan is to number foot-notes 1, 2, 3 and so on, when no alteration on making-up will be required.
The proof-reader must also look after the "widows" and other matters before mentioned. If the book is set in linotype, the make-up will have been unable to make these changes. He will simply allow the proper space and the changes required will be marked by the proof-reader and a number of pages corrected at a time. This is a point of economy.
All corrections having been made and revised, proofs are submitted to the author for his final approval. The author may find it advisable to make alterations even after his book is made up into pages, necessitating further revises; but everything finally being in order, he gives the order to print or to electrotype.
If the pages are to be electrotyped or made into plates, they are "locked up" in an iron frame called a "chase," two or four together, and proofs are given to the proof-reader for a final reading.
If the book is to be printed from the type, the pages are "imposed" in sheets of eight, sixteen, or thirty-two, so arranged that the folios will be in order when the sheet is folded up. They now make what is called a "form," and a proof of this—known as the "stone proof"—is taken for final reading.
The proof-reader now reads the work all through, looking carefully to the spelling, punctuation, and grammar, as in reading "first proof," and more especially looking out for bad or imperfect letters. If many corrections have been made, the type is very apt to be broken and the spacing between words to become irregular. All imperfect letters must be replaced and bad spacing rectified. Then again, commas, hyphens, periods, and thin letters, such as l, f, or t, are apt to slip out of place at the ends of lines. And here a serious source of error may be mentioned which can be found out only by reading the whole page over. In type set on the linotype machine every line is one solid piece of metal. Any correction to be made involves resetting the whole line. Now the compositor in inserting the new line is very apt to take out a line beginning with the same word, replacing it with the new one, thus making a very serious blunder, and of course the proof-reader or author who sees the next proof has no intimation that the wrong line has been tampered with. On reading the page over, however, it will be noticed that something is wrong, previous proofs can be referred to, and the mistake rectified.
The proofs having been finally read, revised, and marked O. K., the pages are sent to the foundry or to press, as the case may be.
But the proof-reader has not done with them yet. If the book is electrotyped, the plates may turn out faulty; sometimes the type will sink in places under the enormous pressure applied in moulding. It is therefore highly advisable that proofs should be taken of the plates and gone over for imperfections; this may save valuable time later when the book is on the press. Some authors don't mind the expense of making changes in their work even after the pages are cast.
The proof-reader only takes leave of the book when it is on the press and all is ready to go ahead and print. A sheet is submitted to him which he must vise for bad letters, see that nothing has fallen out in transit to the pressroom, and that the pressman has not taken out any cuts to underlay and reinserted them upside down. He will also verify the folios again (if the book is printed from plates this will be the first opportunity of doing so) and see that the pages join up to what has gone before. Here his work ends.
PAPER MAKING
By Herbert W. Mason.
The word "paper" derives its name from the ancient Greek word "papyrus," the name of the material used in ancient times for writing purposes, and manufactured by the Egyptians from the papyrus plant, and which was, up to the eighth century, the best-known writing material. Probably the earliest manufacturers of paper were the Chinese, who used the mulberry tree and other like plants for this purpose, and may be called the inventors of our modern paper manufacturing, as they have practised the art of paper making for almost two thousand years.
In the ordinary book papers of to-day the materials used are largely rags and wood fibres. "Esparto," a Spanish grass, is used in England to a great extent, but it is too expensive to import to this country, and is, therefore, not used here. Many other materials could be used to advantage, such as "bagasse," the waste material of sugar cane, and corn stalks, both of which make good book paper; also hemp, wild clover, and other plants which have a good fibre.
Only two kinds of rags are used, linen and cotton, of both of which there are several grades. Linen rags make a very strong paper, and are mostly used in manufacturing fine writing papers, ledgers, and covers for books where strength is necessary. Cotton rags may be divided into three distinct kinds, whites, blues, and colors, and these in turn are subdivided into several grades. Most of the blue rags are now imported from Germany, Belgium, and France; none from Japan as formerly. The whites and colors are bought in this country.
Wood fibres are divided into two classes, the harder woods, such as spruce, fir, etc., and the softer, such as poplar, cottonwood, etc. There are three ways of reducing or disintegrating wood fibres: first, by sulphurous acid or bi-sulphite of lime fumes, which gives the name "sulphite fibre"; second, by caustic soda, which is called "soda fibre"; and third, by grinding. The last is usually only used for stock in very low grades of paper, such as newspaper and wrapping paper; it is rarely used for book paper. Many persons think that this ground wood, which is merely spruce ground very fine into pulp, is used in book papers; but if it were, the paper would not last long, and would almost immediately discolor on exposure to light and air. There is a theory that no paper made from wood fibres is lasting, and that therefore high grades of paper for fine books should be made only of rags, but this is erroneous, for wood stock and rag stock nowadays are treated and prepared in the same way, and only practically pure cellulose matter goes into the paper. It would be a different matter, however, if ground wood were used for fine papers, for in this stock the cellulose matter is not separated.
Rags are usually purchased by the paper manufacturer in solid bales, which have been graded into whites, blues, or colors. After being opened, they are thrown into a thrashing machine, which thrashes and shakes out the greater part of the loose dust and dirt. Later, they are sorted more carefully by hand into several grades, according to their colors and cleanliness. All the woollens, gunny, buttons, hooks and eyes, silks, and foreign materials are thrown aside. As the rags are usually too large to be thrown into the boilers to be cooked, they are cut into very small pieces by means of sharp revolving knives, to which they are fed rapidly from an endless belt. When cut, they are packed into a revolving kettle or boiler, called a "rotary," and cooked with caustic soda and lime for several hours, to disintegrate the fibres, separate the cellulose matter, and "start" the colors. The rags, after coming out of the boiler, look very dark, and are all mashed together. They are then thrown into a tub of water and revolved horizontally by means of a large wheel fitted with radial knives, which tear and bruise them while water continually runs in and out, carrying away the dirt. In a few hours the rags look much cleaner, and a small amount of chlorate of lime and sulphuric acid is run in to bleach them white. After having been thoroughly stirred for a while, the stock is run into what is called a drainer, where it is allowed to stand for several hours to drain off as much water as possible. Liquid chloride of lime, which is used for bleaching, and sulphuric acid is then run over the fibre, which in turn is drained and washed off again. By this time the pulp is white enough to be sent to the beaters, to be prepared for the paper machines, and is called "half-stock."
Wood fibres for book papers are usually treated in the same general way as rags. First, the logs are peeled and are cut into suitable lengths to be thrown into a wood chopper and cut up in very small pieces. If the wood is treated by sulphurous acid or bi-sulphite of lime fumes, it is called the "sulphite process"; if by caustic soda, the "soda process." This wood is cooked in large upright kettles called "digesters." In one case the sulphite fumes are allowed to permeate through the wood under a high pressure, and in the other the caustic soda is put in "straight," and the wood is cooked under a high pressure of steam. This is done to dissolve out all the gum and resins, in order to leave the pure cellulose matter. After the cooking is done, the stock has to be bleached in very much the same way as the rags and washed thoroughly before it is ready for the "beaters."
For "beating," the stock is thrown into a large revolving tub. Rag and wood fibre may be mixed in different proportions, according to the grade of the paper wanted. The stock is then washed a little to be sure that it is clean and white. Water at first is mixed in with the fibre until it is so diluted that it will flow freely; then it is beaten for several hours by means of an iron wheel covered with iron or steel knives about one-quarter of an inch thick, which revolves over an iron bed-plate with similar knives. During this beating process, clay is mixed with the stock, mainly to give the paper a well-filled and better appearance, and not, as most people think, to add weight, although this is sometimes an object. Sizing material is also added, which helps to keep the fibres together and hold the ink in printing. If it is desired to give the paper a white shade, a small amount of aniline blue or pink is mixed in; otherwise it is called "natural" or "unblued."
The beating part of the process of paper making is the most important. The stock has to be beaten up so that all the fibres are separated and broken into just the right lengths according to the weight and strength of the paper to be made. The harder the roll is set down on the bed plate, the shorter the fibre will be and vice versa, but if the roll is not put down hard, the stock has to be beaten so much longer.
"Machining" may be divided into five processes:—
First. When the stock leaves the beater it is run into a large "stuff" chest, and is continually being stirred so that it will not be lumpy. By this time the pulp is about as clean as possible and is ready for the paper machines. The first thing to be done on the machine is to dilute the stock with pure water to the consistency of buttermilk, according to the thickness of the paper required. Then this liquid stock runs through what are called "sand settlers," which are supposed to collect what dirt, iron, etc., remain.
Second. From the sand settlers the stock runs on to a screen, through which it is drawn by means of suction. This process prevents fibres which are lumpy and too long from getting on to the machine, and allows only those of a certain size and length to go forward to be made into paper. An endless and very fine wire cloth, which is continually moving at the same rate of speed as the rest of the paper machine, takes the stock after it has been screened. This is the first step toward making the material into actual paper. Thick rubber straps on each side of the wire determine the width of the paper. This wire shakes a little in order to weave the fibres together while in a state of suspension. At this period the stock looks like thick cream, but soon changes its appearance to the form of a sheet more or less solid on coming to the end of the wire, where there is what is called a "dandy,"—a roll covered with similar wire cloth pressing lightly on the paper as it runs along the wire. Designs in relief on the surface of this roll produce the well-known marks called "water marks." Just beyond the "dandy," underneath the wire, is a suction box which draws enough of the water out so that the paper can go through the "couch" roll at the end of the wire without being crumbled.
Third. The couch roll is a small hard roll covered with a thick felt called a "jacket," and is used on the paper machine to prevent the paper from being crushed, for it presses out much of the water and flattens the paper so that it will pass from the wire to the felts without breaking and through the press rolls without crushing. From this couch roll the paper leaves the wire and is carried along on an endless woollen felt to the press rolls, which are made of hard rubber, steel, or brass. These rolls press the fibres together well, squeezing out more of the water and flattening the sheet.
Fourth. From the press felts the paper is carried to the "dryer felts," which in turn carry the paper to the "dryers," which revolve and by means of the felt carry the paper along to the next dryer, and so on. The dryers are hollow iron or steel cylinders, heated by means of the exhaust steam from the engines which run the machine. More or less steam is allowed to run into the dryers, according to the quality of paper being made.
Fifth. As soon as the paper has been carried over all the dryers, during which time it becomes, perfectly dry, it is run through a set of so-called steel "chilled rolls," at the end of the machine, which are under pressure and which give the paper a fairly smooth surface for ordinary type printing. If a rough surface is desired, the paper is simply wound on reels from the dryers.
Super-calendered papers are those which have a high finish and smooth surface, and are used for cuts, lithographic work, magazine papers, and ordinary illustrations. To calender paper, it is run through a series of alternate "chilled" and "paper" rolls. The chilled rolls are made of steel and have a very smooth and even surface. The "paper" roll is made of circular discs of thin, but strong manila paper, clamped together on an iron shaft, and then put under hydraulic pressure, this pressure being increased constantly until it reaches one hundred tons of pressure to the inch. The rolls are sometimes kept under this pressure for five or six weeks, and then are turned on a lathe into a true and smooth cylinder, and finally burnished by being revolved against each other.
A "cotton" roll, used at times in place of the "paper" roll, is made in the same manner, except it is made of pieces of cotton cloth instead of thin manila paper. There is a heavy pressure on these rolls, and the paper goes through at a high rate of speed. When an especially smooth surface is wanted, steam is run on the paper as it unwinds, dampening it and giving the web a surface like that on ironed linen.
"Coated" paper is treated differently, being covered with a fine coating, which, after super-calendering, gives the paper a glazed and smooth surface for fine half-tone illustrations. Clay, mixed with casein, the product of skimmed milk, or glue, is the chief material used for coating. It is put on the paper by means of large brushes. Then it is dried by fans and passed through a long passageway heated by steam to a high temperature. After being reeled, it is allowed to stand for a while to harden; then is run several times through the calenders to get the smooth surface. If a high, glazed finish is necessary, steam is put on while running through the calenders. This gives a very bright surface for fine lithographic work. For the best coated papers, instead of clay, sulphate of lime and sometimes sulphate of barium is used, with glue or casein. Formaldehyde, a chemical compound, is used to prevent decomposition in the coating materials; and soda or borax is used to "cut" or dissolve the casein or glue.
If the paper is to be printed "from the web," that is, from the roll, it first has to be trimmed to the correct width, then wound tightly under a high pressure to a certain thickness, then the rolls are packed up in wrapping paper ready to be shipped. Some rolls contain as much as five miles of paper. When the paper is to be put up in sheets, it has to be cut to exactly the correct width and length on the cutting machine. It is all very carefully sorted—the imperfect sheets being thrown out—counted and packed in wooden cases, or done up with strong wrapping paper in bundles, ready to be sent to the printer.
PRESSWORK
By Walter J. Berwick.
Books are printed in "forms," or sheets, of four, eight, twelve, twenty-four, or thirty-two pages at a time, the number being determined to a great extent by the size of the type page and by the class of the work.
An ordinary twelvemo book, without illustrations in the text, is usually printed in forms of thirty-two pages, on what is known as a single-cylinder flat-bed press, which prints only one side of the paper at an impression. For large editions, the size of the sheet of paper is sometimes doubled and sixty-four pages printed at a time. The class of work in question may also be printed on perfecting presses which print both sides of the paper at one time, and in this way as many as one hundred and twenty-eight pages are frequently printed on one sheet, there being sixty-four pages on each side. Large editions of books having small pages, such as small Bibles, are often printed two hundred and fifty-six pages (one hundred and twenty-eight on each side) at one time.
High grade, illustrated books are always printed on one side of the sheet at a time, the reverse side being printed after the first impression has dried properly. Thus a smooch, or "offset," the result of handling the paper before the ink has become dry, is prevented.
For convenience, I shall describe the process of printing a book from electrotype plates on a press which prints thirty-two pages at a time and on only one side of the paper.
Before ordering his paper, the publisher must first determine the size of the paper page of his proposed book, and from this arrive at the necessary size of the sheets of paper. He must also determine the thickness of the paper needed to give the finished book its proper bulk.
If the book is to be trimmed on top, bottom, and front, about one-eighth of an inch must be allowed on top and front for the binder to trim off, and about one-fourth of an inch on the bottom. The dimensions from back to front, including the amount left for the "trim," should be multiplied by eight; and the page dimension the other way, including the trim, by four. This would give the size of paper needed. As an illustration, if the trimmed size of a book is 7-7/8 x 5-3/8 inches, the paper should be 32 x 44 inches. If the book is printed 16 pages at a time, the paper should be 22 x 44; and if 64 pages at a time, 44 x 64.
The quality of the paper and the size of the sheet being decided upon, and the number of pages known, any large paper house can tell the weight necessary to give the required thickness to the book.
On receipt of the printing order, with directions as to whether the book is to be trimmed or not, the printer first makes up what is called a "form" of so-called "patent" blocks on which the stereotype or electrotype plates are placed during the printing of the book. These blocks are made of wood or iron planed to an even thickness of about three-fourths of an inch, so that when an electrotype plate is placed upon one, it will take only a few thicknesses of thin paper between it and the electrotyped page to make the whole "type-high," that is, as high as an ordinary piece of type.
Two adjacent edges of these blocks are bound with strips of brass, which project above the block and are turned over slightly, so as to receive the two bevelled edges of the electrotype plate. The other two edges are provided with movable clamps, which are screwed tight against the flat edges of the electrotype plate by means of ratchets, thus holding the plate firmly in its place.
In practice, the longer of the two brass-bound edges is called the "back" of the block and the shorter one the "head," the other long edge being known as the "front" and the other short edge, the "foot." These terms, as a matter of fact, originated from the use of the same words in describing the printed page of a book, the "back" corresponding with the side of the page next to the binding of the book, the "head" being the top of the book, and so on.
One-half of a set of blocks—thirty-two being a set in this case—are made with the backs on the left and one-half with the backs on the right edge of the block. The common way is to place thirty-two of these blocks, in four rows of eight blocks each, in a "chase," or iron frame, with a cross-bar in the centre. Thus sixteen blocks are on each side of the cross-bar, and all have their backs toward it. The form then appears like this:—
Strips of wood, called "furniture," are then used to fill up the spaces between the blocks, care being taken to see that all the backs, fronts, and heads are in uniform positions. As some people prefer the printed pages of a book to be near the centre of the paper pages, while others like the head and back margins to be much narrower than the margins at the front and foot, the distances between the blocks must be arranged according to the taste of the publisher or the author.
After the blocks have been spaced as desired, and the spaces filled with furniture, the form is "locked up," or tightened securely, with wedge-shaped pieces of iron called "quoins," and it is then placed in position on the bed of the press, securely fastened by screw clamps, and "making ready" for printing is begun.
Notwithstanding the care that has been taken to have all the "patent" blocks and the electrotype plates of even and uniform thickness, there is almost never a case where a form can be put on the press and printed off properly without considerable work being required to make the surface of the plates absolutely flat so that the entire printed part of the page will receive the same amount of ink and will press evenly on the paper.
The first step in making a press "ready" is to place a sheet of heavy cardboard around the cylinder, and over it draw a smooth piece of muslin or cotton cloth. This is called the "packing." In many of the best offices this sheet of heavy cardboard is not used, but in its place is a patent make-ready called "Tympalyn."
Over this a thick sheet of manila paper is shrunk, it being pasted under clamps on the front of the cylinder, and carried around and fastened to hooks on a rod on the back. The rod is then turned until the sheet is perfectly tight and smooth.
While the pressman is laying out his plates the feeder should be cutting thin sheets of paper the size of one of the plates. Some of these papers are cut about one inch shorter than the plates for "bevels," and these are pasted on the middle of the full-size pieces. These bevels and the larger "blank" sheets are to go between the plates and the blocks to overcome any variation there may be in the thickness and to make the surface of the form as nearly level as possible. The "bevels" raise the centres very slightly above the edges of the plate, thus reducing the pressure of the cylinder at the points of contact and departure, and saving the plates from wear.
The cylinder being properly packed, and the form of blocks fastened on the press so that the impression of the form will come in the middle of the paper sheets, it is necessary to know whether the binder is to fold the sheets by hand or by machine, and if the latter, what kind of machine, as different ones require different "imposition" or arrangement of pages. This being decided, the plates are fastened on the blocks so arranged that when the sheet is cut and folded the pages of the book will run consecutively. Before levelling up the form with the bevels and blank sheets, the plates of all open or short pages, if any, are replaced with solid pages, as these sheets and underlay are to remain through the printing of all the forms of the book. The rollers are now put in the press and adjusted to just touch the inking table, the ink put on the rollers and distributed, and one impression printed on one of several sheets of thin paper which are run through the press together.[3] This printed sheet is then turned face down by the pressman and any unevenness of the impression noted. One of the printed pages is taken as a standard and by removing as many pieces of the thin sheets as necessary from under the plates where the impression is too heavy, and by adding where it is not heavy enough, the surface of the form is finally "evened," or made as nearly equal as possible.
[Footnote 3: If one sheet of paper were run through the press before "making ready," it would not receive any impression, there being a space equal to the thickness of ten sheets of paper between the cylinder and the surface of the type. A bunch of six or eight sheets is therefore run through to get an impression for "make-ready" purposes.]
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.
The first printing press was the "wooden screw" press, which came into use about the middle of the fifteenth century, and was built upon the same mechanical principle as the linen presses in the homes of the well-to-do. This was the press used by Gutenberg.
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.
An accurate description of this press is not extant, but it is known to have consisted of a large wooden frame, a platen worked by a vertical screw and gears, a type-bed drawn forward and backward by means of straps fastened to a large roller underneath the bed, a tympan frame and frisket arranged to open and close automatically with the movement of the bed, and an inking apparatus, consisting of an ink-box with a narrow slit in the bottom through which the ink was forced by a piston upon a roller below, from which it was transmitted by two intermediate rollers to another and lower roller which inked the form as it passed underneath. The two intermediate rollers had an alternating, lateral motion which spread or distributed the ink sideways before it reached the lowest roller.
This press was the first to have ink-distributing rollers and the first to be run by steam power. In April, 1811, the "Annual Register" for 1810 was printed on it by Mr. Bensley at the rate of eight hundred impressions an hour. Nothing further is recorded about this press, and it was probably abandoned as being too complicated.
In the following year, Koenig's first cylinder press was completed, to be followed two years later by an improved cylinder press made for the London Times, which will be referred to farther on.
In his experiments, the Earl of Stanhope had tried, without success, to find a substitute for inking-balls by making rollers covered with different kinds of skins. He also tried other materials, such as cloth, silk, etc., but the unavoidable seam and the impossibility of keeping these materials soft and pliable defeated his purpose. About 1813 inking-rollers made of a composition of glue and molasses came into general use, and this important invention was of great assistance in the further improvement of the printing press.
Other cylinder presses with mechanical inking appliances were devised and patented, the most notable of which were those of Rutt, Bacon, Cowper, Applegath, and Napier, but the mechanical imperfections of these presses unfitted them for the better grades of book printing.
Further efforts were, therefore, directed to increasing the output of the bed and platen presses by the application of improved inking devices, sheet-feeding, and impression mechanisms. About 1825 there was constructed by D. Napier, a machinist in London, a press containing such appliances which produced six to seven hundred impressions an hour. Other presses constructed upon the same principle, but with two type-beds, two sets of friskets, two inking mechanisms—and only one platen, in the centre of the press—were made by Hopkinson & Cope and by Napier, and were known as "double platen machines," though this is really a misnomer as there was only one platen.
Napier's invention achieved the greatest popularity and came into general use. At each end of his press there was an inking device, a type-bed, and a frisket, each set of which operated alternately with the other, but either could be made inoperative if the "feeder," or "layer-on," failed to place the sheet in time. Four boys, besides the printer, were required—two to lay on, and two to take off the sheets.
When the type-bed and the frisket carrying the sheet of paper were in position under the platen, the latter was drawn downward to make the impression by means of a "toggle" joint which acted upon two strong rods, one on each side, and was then raised again by a counterbalance weight. Owing to the awkward method of handling the paper, the working speed of the press was necessarily slow, and the size of the sheets limited to double royal, or 25 x 40 inches.
The best presses of this type were those devised and patented by Isaac Adams, of Boston, in 1830 and 1836, and by Otis Tufts, also of Boston, in 1834. R. Hoe & Co., of New York, acquired Adams' business in 1858 and continued the manufacture of his presses. Over one thousand in many different sizes were made by this firm, the largest printing a sheet 33 x 46 inches at a working speed of one thousand impressions an hour. The last Adams press was made in 1882, but quite a number are still in use in prominent printing-offices in New York, Boston, and a few other cities, where the results on fine book work are still considered better than from the faster cylinder presses. The mechanical principle employed in the Adams press for exerting a flat, parallel pressure has now been generally adopted for heavy stamping and embossing presses.
To go back to the early part of the nineteenth century, when Koenig found his bed and platen press impracticable, he immediately set to work, assisted by one of his countrymen, Andreas Bauer, a mechanic who had helped him formerly, and in the latter part of 1812, the first flat-bed cylinder press was erected by them in Bensley's office. The cylinder of this press had three impression surfaces with spaces between them, and each covered with a soft blanket. With each forward movement of the type-bed the cylinder made one-third of a revolution and then came to a standstill, while the bed returned to its starting-point. The spaces between the impression surfaces allowed the type-form to pass under the cylinder without touching the blankets. At the end of the cylinder and at equal distances along its circumference were hinged three frisket frames, each fitted with tapes having reel springs at one end. The frisket frame of the uppermost impression surface rested in a vertically inclined position against the high framework of the inking mechanism. The sheet of paper was placed upon the blanket, and the cylinder then turned forward, drawing the frisket frame down with it, while the tapes, kept taut by the reel springs, adjusted themselves to the curvature of the cylinder and held the sheet upon it. After one-third of a revolution, the cylinder came to a stop to let the type-bed return. On the next forward movement of the bed and the next one-third of a revolution of the cylinder, the impression was made, and on the next repetition of these movements, the sheet was taken off by hand, and the cylinder returned to its original position to have another sheet placed on the first frisket. At every complete revolution of the cylinder and three complete reciprocating movements of the bed, three sheets were printed.
The inking mechanism was similar to that employed on the bed and platen press, but the mechanism for forcing the ink through the slit in the bottom of the fountain was improved. The inking-rollers were covered with leather as before. The type-bed was moved by a very ingenious mechanism which is in use even at the present time, and is described farther on, when the two-revolution press is mentioned. The different parts were not connected with each other, the cylinder, the type-bed, the inking-rollers, and the fountain being operated independently by separate driving mechanisms. This press printed eight hundred sheets an hour, on one side. A part of Clarkson's "Life of William Penn" was printed on this press, and was the first book ever printed on a cylinder press.
Printers and publishers were sceptical as to the practical value of this novel invention, but Mr. John Walter, the proprietor of the London Times, with better foresight than the others, and needing increased facilities for printing his paper, contracted for two presses, each to have two impression cylinders. These were constructed for him with great secrecy in a building adjoining the pressroom of the Times, and on November 28, 1814, the entire edition of that paper was printed on them,—the first cylinder presses driven by steam power.
The mechanical principles were the same as in the first cylinder press. There were two impression cylinders, but only one type-bed, and the latter had, therefore, to travel a greater distance than in the single-cylinder press. This made it impossible to obtain quite double the output of the single-cylinder press, but each of these new presses produced eleven hundred impressions an hour, a very respectable performance for that early stage. The threefold motion of the cylinders was retained, but the frisket frames were displaced, and tapes running over rollers and underneath the cylinders held the sheets against the impression surfaces. An improvement was also made in the inking mechanism by the addition of an intermediate roller between the fountain and the upper distributing cylinder roller.
The next step in advance was the construction of the first of the so-called perfecting presses, which was patented, December 24, 1814, and erected in Mr. Bensley's office in 1815 or 1816. This press had two type-beds and two impression cylinders, one of each near either end of the press. The cylinders instead of having a threefold motion revolved continuously. The circumference of each corresponded approximately to the distance traversed by one of the beds. The part of the cylinder which made the impression was a little larger in diameter than the remainder, the low portion giving the necessary room for the type-bed to return without touching it. The board from which the sheets were "fed" was near the centre of the press, and at the top adjoining the feed board was an endless belt made of cloth as wide as the board and running with an intermittent motion over two rollers.
The sheet of paper was laid upon this belt, which then moved forward, carrying the sheet between the tapes and leading it to the top of, down and around, the first cylinder where it received the first impression. Thence the sheet was conveyed by the tapes to the top of and around the second impression cylinder and was printed on the reverse side, that is "perfected," and it was then taken from the lower side of the second cylinder by hand and laid upon a board in the centre of the press, between the two impression cylinders and underneath the feed board. This press printed both sides of a sheet 21 x 34-1/2 inches at a speed of nine hundred to one thousand an hour.
Shortly afterward a single-cylinder press was constructed upon the same principle, the forerunner of what is now known as the single large or drum cylinder press.
Within the next few years, Applegath and Cowper greatly simplified the presses in the Times and in Bensley's office by removing many of the gear wheels. They also invented the first inking-table, a flat, iron plate attached to the type-bed which enabled the rollers to distribute the ink more evenly than before. They placed rollers at an angle across the ink-table and introduced the revolving roller and the scraping blade in the ink-fountain.
More important, however, were Napier's inventions about 1824, of "grippers" which seized the sheet of paper at its front edge and drew it from the feed board, while the cylinder was in motion, and of a method of alternately depressing and raising the impression cylinders on the forward and backward stroke of the type-bed, making it unnecessary to have a part of the cylinders of smaller diameter than the rest to allow the type to pass under it as the bed returned. This made it possible to use cylinders of a smaller diameter. These improvements were first embodied in a perfecting press made for Hansard, a London printer.
Although a number of presses were already being operated by steam power, Hansard, in his description of the Napier bed and platen press (the "Nay-Peer," he called it) finds a peculiar advantage in that "it supersedes the necessity of steam power, as the motion of this machine is gained by two men turning a fly-wheel which acts as the impelling power."
I have described the development of the printing press up to this state with considerable detail, because it discloses the main principles of the book press of the present day. During the first quarter of the last century, the manufacture of cylinder presses was confined to England, not only because London was then the leading centre of civilization, but because nowhere else could be found the mechanical facilities for constructing the large metal frames and parts. Koenig left London for his native land in 1817, dejected by the treatment he had received at the hands of Bensley, both in financial matters and in the attempts to disparage his achievements. He was followed two years later by his friend Bauer, and together they founded the firm of Koenig & Bauer at Oberzell, where it still thrives as one of the largest factories in Germany.
It was not long, however, before the United States took the lead in the number of presses manufactured as well as in their improvement, and the present high state of efficiency of American presses makes them models which are copied in all other countries. These improvements and the perfections of details often presented problems which were more difficult to solve than those of the earlier inventors, and thousands of patents have been granted to Americans for new and ingenious devices.
The firm of R. Hoe & Co., which as early as 1822 was already engaged in the manufacture of hand-presses in New York, commenced about 1832 to manufacture flat-bed cylinder presses, beginning with the single large or drum cylinder press which was followed soon afterward by the single small cylinder and the double small cylinder press, the flat-bed perfecting press, the stop-cylinder press, the two-revolution press, and the rotary book press. They also made and are still making large newspaper and color presses which are used all over the civilized world, but of these we will not treat here.
As stated at the beginning of this article the chief object in press making has always been to lessen the cost of printing, but after increased speed had been attained, there came a demand for a press that would produce the finest quality of printing without sacrificing the quantity produced.
To meet this no press has ever surpassed the stop cylinder. It has been made in several different sizes, the largest having a type-bed 45 x 65 inches. Resting upon and attached to a heavy iron foundation are two iron side frames which are securely braced together by an upper iron frame, called the "rib." This upper frame contains four tracks faced with hard steel, on which run a series of friction rollers, supporting the iron type-bed. Attached to the front of the type-bed is an iron plate, called the ink-table, its surface level with the surface of the type-form as it lies upon the bed.
At the front of the press is the ink-fountain and a number of steel and composition rollers, called the "distributing rollers." The ink is delivered a little at a time from the fountain to the revolving distributing rollers, and from them to the ink-table which moves under the rollers with the motion of the type-bed. By this means the ink is distributed upon the entire surface of the ink-table in a thin, even film. From the ink-table the ink is taken by a set of six rollers, called the "form rollers." Resting on the form rollers and moving in contact with them are additional rollers which help to distribute the ink still finer before it reaches the type.
The impression cylinder is located at a distance from the front of the press of about two-thirds of the entire length of the press. The circumference of the cylinder is equal to the distance that the type-bed travels in one direction. When the type-bed moves from the front to the rear, the cylinder rotates in unison with it, and thus the cylinder makes one revolution. While the bed returns the cylinder does not move.
Near the rear of the press is a large wooden board extending across the press and lying in a slightly inclined position with its lower edge almost directly above the centre of the impression cylinder. This is the "feed board" upon which the sheets of paper lie before they are printed. The impression cylinder has a set of grippers, and when the cylinder is at rest, these grippers are close to the edge of the feed board and stand open to receive the edge of the sheet of paper. Extending a little over the front of the feed board are two gauges against which the front edge of the sheet of paper is placed, while one side edge of the sheet is placed against a gauge at the side of the feed board. Just an instant before the cylinder commences to rotate, the grippers seize the front edge of the sheet, and the gauges lift out of the way. The cylinder then carries the sheet around, meets the moving inked form, and makes the impression. Before the cylinder completes its revolution, the grippers open and release the sheet, and at the same instant another set of grippers on an adjoining cylinder, called the "delivery cylinder," seize the sheet. From this delivery cylinder the sheet runs down over a set of strings, and is lifted off the strings by a sort of fan, or "sheet flier," and deposited on a table at the rear of the press. This method of delivering the sheets is known as the cylinder or rear delivery. This press may also be fitted for "front delivery." By this method the sheet of paper after being printed is carried around on the impression cylinder until the front edge comes again to the feeding point. Just as the impression cylinder comes to a stop, a set of grippers seize the front edge of the printed sheet, draw it over and away from the impression cylinder, and deposit it, with the printed side up, upon a table near the front of the press and above the ink-fountain and distributing rollers.
The average speed of one of these presses is from one thousand to fifteen hundred impressions an hour, depending upon the desired quality of the work.
Notwithstanding the excellent qualities of the stop-cylinder press, commercial necessities often demand a sacrifice of quality to speed, and this has brought the two-revolution press into very general use. As the name implies, the cylinder makes two revolutions, one to print the sheet, and the other, an idle one, to allow the bed to return. While the bed is returning, the impression cylinder is lifted to clear the type-form. As the cylinder rotates continually at a uniform speed, the type-bed must also travel at a constant speed. The reversal of the movements of the bed must, therefore, take place in a short space of time.
The study of inventors has been concentrated upon this subject more than upon any other connected with flat-bed presses, and hundreds of patents for "bed motions" have been taken out. Considering the fact that in the larger presses the weight of the bed and form is about one and a half tons and that this weight moving at a speed of about six feet in a second must be brought to a full stop and put into motion again in the opposite direction at full speed in about one-quarter of a second, it is obvious that the problem was not an easy one, especially when the reversal of the bed must be accomplished without a jar or vibration. The mechanism employed has always been a driving gear and one or two toothed racks. In Koenig's original movement, the driving gear on the end of a rising and falling shaft ran on top of a rack attached to the bottom of the bed in order to drive the bed in one direction, and then descending around the end of the rack ran in the bottom to the same rack to drive the bed in the other direction and ascending at the other end to repeat the movement. This, as already stated, has proven a very efficient mechanism and is employed, with improvements, by some of the press manufacturers of the present time.
In a pamphlet entitled "A Short History of the Printing Press" (New York, 1902), by Robert Hoe, the writer describes a method of reversing the bed. Although somewhat technical, it seems desirable to quote him as follows: "As early as 1847, Hoe & Co. patented an entirely new bed-driving mechanism. To a hanger fixed on the lower side of the bed were attached two racks facing each other, but not in the same vertical plane, and separated by a distance equal to the diameter of the driving wheel, which was on a horizontal shaft and movable sideways so as to engage in either one or other of the racks. By this means, a uniform movement was obtained in each direction. The reversal of the bed was accomplished by a roller at either end of the bed entering a recess in a disc on the driving shaft, which in a half-revolution brought the bed to a stop and started it in the opposite direction. This involved a new principle; a crank action operating directly upon the bed from a shaft having a fixed centre, and within recent years modifications of this patent have been successfully employed to drive the type-bed at a high velocity and reverse it without a shock or vibration."
This invention appears to have been the forerunner of the more recent improvements in bed motions. A notable one is that employed in the Miehle presses, which have gained much celebrity, run at a high rate of speed, and are used in many printing-offices in this and other countries. The reversal of the bed movement is accomplished by a so-called "true crank" movement and with an absence of jar and vibration never before obtained in any other than the stop-cylinder presses.
At the present time, the latest development in printing presses is Hoe & Co.'s new two-revolution press, in which, also, the reversal of the bed is accomplished by the true crank movement, but with an improvement which brings it to an easy stop and returns it without the least vibration.
On all two-revolution presses there are employed, to assist in the reversal of the bed, air-chambers or cylinders, without which the reversing mechanisms could not withstand the enormous strain to which they are subjected. These are iron cylinders, closed at one end, approximately six inches in diameter and eighteen inches long, and varying in size according to the size of the press. Some presses have two and others four of these cylinders, one or two at each end. The open ends of the cylinders are toward the bed, and attached to the bed are two or four pistons which enter the air-chambers as the bed nears the end of its stroke. The compression of the air in the cylinders makes a cushion and checks the momentum of the moving bed. The pistons can be adjusted to regulate the air compression to suit the velocity of the bed and the weight of the form, which vary in different kinds of work.
The delivery of the printed sheets is performed either by a delivery cylinder or by a front delivery with the printed side of the paper uppermost as already described for the stop-cylinder presses. Grippers are not used in the front delivery carriage, as the sheet is discharged from the cylinder by its continuous rotation.
The average running speed of a two-revolution press is about one-third greater than that of a stop cylinder, or about eighteen hundred impressions an hour, as against from one thousand to thirteen hundred and fifty impressions from the stop cylinder, this being the comparison in presses of the average size, printing sheets about 33 x 46 inches. The driving power required is in the proportion of about five for the two-revolution press to three for the stop cylinder, and the wear and tear is in about the same proportion.
Another press, which is still employed to a small extent for book-work, is the flat-bed perfecting press. This press is virtually two two-revolution presses combined into one, with the advantage that they require only one man as "feeder," but with the disadvantage that they produce only about two-thirds as much work as two separate single-cylinder, two-revolution presses. Their greatest disadvantage lies in the difficulty of preventing the fresh ink on the side of the sheet first printed from "setting off" on the packing of the cylinder which prints the reverse or second side. Mechanisms are employed to move the "tympan sheet" or outside covering of the second cylinder along at fixed intervals, but they are complicated and troublesome. These presses are expensive and cumbersome, and can generally be used only for inferior grades of work in large editions. Under the care of a skilful and painstaking pressman, good work can be produced from them, but fine book-work is always done on stop-cylinder and two-revolution, single-cylinder presses, which have now been brought to a high state of perfection.
Nearly a hundred years ago Hansard wrote, "The printing machine in its present state appears susceptible of little improvement." He was, in truth, right so far as the main principles of the flat-bed cylinder press are concerned, but there have been immense improvements in many of the details. With the introduction of automatic sheet-feeding devices, and improvements in the driving, inking, and delivery arrangements, mechanical ingenuity seems to have been exhausted. The temptation is strong to apply Hansard's prediction to the flat-bed cylinder press of the present day, but with the many surprises that meet us in other fields this would border on temerity.
Already there have been great advances in adapting the entirely rotary principle to the printing of high-grade work, although its use is still restricted to the production of large editions.
As early as 1852 Hoe & Co. made a rotary press for D. Appleton & Co., especially for printing the famous Webster spelling-book. The types were locked up on the cylinders in curved beds, called "turtles," and the sheets were delivered by a sheet-flier. Probably thirty million copies were printed on this press, which was dismantled nearly twenty-six years ago.
In 1886 this same concern made a press which is still used for printing some of the forms of the Century Magazine. This press had two pairs of cylinders, and curved electrotype plates were used on it. The paper was in a roll at one end, and at the other end there were delivered, to each revolution of the cylinders, eight eight-page signatures already folded to the size of the Century page. This was the first rotary press made for a good grade of book-work. Two similar presses were afterward made for Harper's Weekly and for the Strand Magazine of London.
What is known as the rotary art press was made in 1890 for printing the fine half-tone illustrations in the Century Magazine.
This has one plate cylinder and one impression cylinder, and curved electrotype plates are used. The sheets are "fed" by hand in the usual manner, and are printed on one side at a time and delivered by a sheet-flier. It produces as much work as four flat-bed cylinder presses and of better quality. The plates are inked by sixteen rollers. The performance of this press is another demonstration of the superiority of the rotary over the flat-bed principle of printing.
Since then hundreds of rotary presses have been made for magazine and book printing, most of them equipped with attachments for folding the sheets as they are printed, and all having a high rate of speed. C. B. Cottrell & Co. have made many rotary presses for magazine printing, most of which deliver the sheets flat, without folding, and most of them made to suit some predetermined size or sizes of sheets or pages.
In the evolution of the printing press there are three sharply defined stages: first, the flat impression surface and the flat printing surface, requiring the exertion of all of the impressing power upon the entire surfaces; second, the cylindrical impression surface and the flat printing surface, requiring the exertion of all of the impressing power upon only a narrow line or a small portion of the printing surface; third, a cylindrical impression surface and a cylindrical printing surface, still further reducing the area upon which all the impressing power is exerted.
Just as the second stage has, particularly for book-work, virtually superseded the first, so the third is destined to supersede the second. It is only an adaptation of the means to the ends. The mechanical principles of the rotary press are, in fact, simpler than those of the flat-bed cylinder press, and it may be said that so far as the purely mechanical part of the press is concerned, they have been fully developed, but much still remains to be done in other directions. The variety in the sizes of the pages of different books, the smallness of the editions, and the fact that the finer grades of paper, especially coated paper, cannot be obtained in roll form, are obstacles to be removed. As most book forms are electrotyped for flat-bed presses, and as it requires but little additional expense to curve the plates, this one item is not much of an obstacle to overcome. It is, however, still difficult to curve the plates perfectly, and the pressmen, even if they can produce excellent work from flat-bed presses, require considerable training if they have had no experience on rotary presses. All these difficulties are sure to be overcome in time.
PRINTING INK
By James A. Ullman.
The process of making printing ink consists of grinding a pigment, black, white, or colored, into a suitable varnish. The pigment is that constituent which makes the impression visible, while the varnish is the vehicle which carries the pigment during the operation of grinding and during its distribution on the press to the type, from the type to the paper, and ultimately binds it to the paper.
A complete factory for the production of printing ink consequently consists of three distinct plants,—one for the production of the varnishes, one for the manufacture of the pigments, and one for the grinding of the pigments into the varnishes.
Roughly speaking, the varnishes are divided into three classes, the first and second of which are the varnishes proper, i.e. the resin and the linseed varnishes, while the third class consists of dryers, etc., whose purpose is to influence the drying and consistency of the inks.
Taking up first the proper varnishes, we find that these are produced by the destructive distillation of resin in huge cast-iron stills. By this process, the solid resin of colophony is split up into water, various resinic acids or naphthas, and resin oils of various specific gravities and consistencies, all of which are separated from each other into separate containers which are ready to receive them. As one distillation is not sufficient to purify the resin oils from the water and acid, which would not only give the resulting ink an obnoxious odor but be detrimental to type, plates, etc., the distillation is repeated a number of times until the oils become perfectly pure. The grades of varnishes made from these resin oils are used for the cheaper classes of printing inks, not only on account of their lower cost, but because they are more suitable for the class of work for which such inks are used.
The linseed varnishes are made by boiling refined linseed oils at a very high temperature. The linseed oil loses its acrid elements by volatilization, and gradually becomes thick and viscous, the various "numbers" or consistencies of these varnishes being dependent upon the length of time during which the oil is subjected to the process, and to the temperature applied.
The dryers are made by adding to the linseed oil during the boiling, suitable oxidizing agents, such as compounds of lead or manganese, by means of which the oil is chemically affected, i.e. it is oxidized. Such dryers, when added to printing ink, attracts the oxygen of the air and transfer it by catalytic action to the varnish of the ink, thus causing it to oxidize more rapidly, or to become, as it is commonly called, dry.
Having disposed of the manufacture of the varnishes and dryers, we now come to the manufacture of pigments. This is such a large field that it can be only cursorily covered within the limits of a short article. The pigments are of many kinds and classes. The blacks alone would form a large chapter by themselves; yet all of them consist of carbon, produced by the combustion of hydrocarbons of various kinds, and according to their origin they are the so-called carbon blacks, lamp blacks, spirit blacks, oil blacks, Frankfort blacks, etc., each of which has its distinct and peculiar properties and value for its specific purpose. |
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