The origin and early history of paper as a writing material are involved in much obscurity. The art of making it from fibrous matter, and, among other substances, from the wool of the cotton plant, reduced to a pulp, appears to have been practised by the Chinese at a very distant period. Different writers have traced it back to the 2d century B.C. But however remote its age may have been in eastern Asia, cotton paper first became available for the rest of the world at the beginning of the 8th century, when the Arabs captured Samarkand (704 A.D.), and' there learnt its use. The manufacture was taken up by them in that city, and rapidly spread through all parts of their empire. From the large quantities which were produced at Damascus, it obtained one of the titles, charta Damascena, by which it was known in the Middle Ages. The extent to which it was adopted for literary purposes is proved by the comparatively large number of early Arabic MSS. on paper which have come down to us, dating from the 9th century.
With regard to the introduction of paper into Europe, it naturally first made its appearance in those countries more immediately in contact with the Oriental world. Besides receiving the names of charta and papyrus, transferred to it from the Egyptian writing material manufactured from the papyrus plant (see PAPYRUS), cotton paper was known in the Middle Ages as charta bombycina, gossypina, cuttunea, xylina, Damascena, and serica. The last title seems to have been derived from its glossy and silken appearance. It was probably first brought into Greece through trade with Asia, and from thence transmitted to neighbouring countries. Theophilus presbyter, writing in the 12th century (Schedula diversarum artium, i. 23), refers to it under the name of Greek parchment" tolle pergamenam Grsecam, quae fit ex lana ligni." In the 10th century bambacinum was used at Rome. There is also a record of the use of paper by the empress Irene at the end of the 11th or beginning of the 12th century, in her rules for the nuns of Constantinople. It does not appear, however, to have been very extensively used in Greece before the middle of the 13th century, for, with one doubtful exception, there are no extant Greek MSS. on paper which bear date prior to that period.
The manufacture of paper in Europe was first established by the Moors in Spain, the headquarters of the industry being Xativa, Valencia, and Toledo. But on the fall of
Soc., pis. 7, 21). In the great collection of Syriac MSS. which were obtained from the Nitrian desert in Egypt, and are now in the British Museum, there are many volumes written on cotton paper of the 10th century. The two oldest dated examples, however, are not earlier than 1075 and I084 A,D, the Moorish power the manufacture, passing into the hands of the less skilled Christians, declined in the quality of its production. In Italy also the art of paper-making was no doubt in the first place established through the Arab occupation of Sicily. But the paper which was made both there and in Spain, it must be remembered, was in the first instance cotton paper. In the laws of Alphonso of 1263 it is referred to as cloth parchment, a term which well describes the thick material made from cotton. As, however, the industry was pushed north, into districts where cotton was not to be found as a natural growth or was not imported, other substances had to be pressed into the service. Hence by degrees arose the practice of mixing rags, in the first instance no doubt of woollen fabrics, with the raw material. The gradual substitution of linen, in countries where it was more abundant or where it was the only suitable material at hand, was a natural step in the progress of the manufacture.
The first mention of rag paper occurs in the tract of Peter, abbot of Cluny (1122-50 A.D.), adversus Judaeos, cap. 5, where, among the various kinds of books, he refers to such as are written on material made " ex rasuris veterum pannorum." At this early period woollen cloth is probably intended. Linen paper was first made in the 14th century; but in the first half of that century it is probable that woollen fabrics still entered largely into the component parts of the pulpa fact which, however, can only be proved in individual instances by aid of the microscope. This being the case, it is of less practical advantage to try to ascertain an exact date for the first use of linen in paper-making than to define the line of demarcation between the two classes of paper, viz., that made in the Oriental fashion without water-marks, and that in which these marks are seen. The period when this latter kind of paper came into existence lies in the first years of the 14th century, when paper-making at length became a veritable European industry. Cotton paper of the Oriental pattern, it is true, is still found here and there in use some time after the manufacture of the water-marked material had begun, but the instances which have survived are few and are mostly confined to the south of Europe.
A few words may here be said respecting the extant examples of cotton paper MSS. written in European countries. Several which have been quoted by former writers as early instances have proved, on more recent examination, to be nothing but vellum. The ancient fragments of the Gospel of St Mark, preserved at Venice, which were stated by Maffei to be of cotton paper, by Montfaucon of papyrus, and by the Benedictines of bark, are in fact written on skin. The oldest document on cotton paper is a deed of King Roger of Sicily, of the year 1102; and there are others of Sicilian kings, of the 12th century. The oldest known imperial deed on the same material is a charter of Frederick II. to the nuns of Goess in Styria, of the year 1228, now at Vienna. In 1231, however, the same emperor forbade further use of paper for official documents, which were in future to be inscribed on vellum. In Venice the Liber plegiorum, the entries in which begin with the year 1223, is made of rough cotton paper; and similarly the registers of the Council of Ten, beginning in 1325, and the register of the emperor Henry VII. (1308-13) preserved at Turin, are also written on a like substance. In the British Museum there is an older example in a MS. (Arundel 268) which contains some astronomical treatises written on an excellent paper in an Italian hand of the first half of the 13th century. The letters addressed from Castile to the English king, Edward I., in 1279 and following years (Pauli in Bericht. Berl. Akad,, 1854) are instances of Spanish-made paper; and other specimens in existence prove that in this latter country a rough kind of charta bcmbyeina was manufactured to a comparatively late date.
In Italy the first place which appears to have become a great centre of the paper-making industry was Fabriano in the marquisate of Ancona, which rose into importance on the decline of the manufacture in Spain. The jurist Bartolo, in his treatise De insigniis et armis, refers to the excellent paper made there in the middle of the 14th century, an encomium which will be supported by those who have had occasion to examine the extant MSS. of Italian paper of that period, which even now excites admiration for its good quality. In 1340 a factory was established at Padua ; another arose later at Treviso ; and others followed in the territories of Florence, Bologna, Parma, Milan, Venice, and other districts. From the lino of factories of northern Italy the wants of southern Germany were supplied as late as the 15th century. As an instance the case of Görlitz has been cited, which drew its paper from Milan and Venice for the half century between 1376 and 1426. But in Germany also factories were rapidly founded. The earliest are said to have been set up between Cologne and Mainz, and in Mainz itself about the year 1320. At Nuremberg Ulman Stromer established a mill in 1390, with the aid of Italian workmen. Other places of early manufacture were Ratisbon and Augsburg. Western Germany, as well as the Netherlands and England, is said to have obtained paper at first from France and Burgundy through the markets of Bruges, Antwerp, and Cologne. France owed the establishment of her first paper-mills to Spain, whence we are told the art of paper-making was introduced, as early as the year 1189, into the district of Herault. The French paper of this early date was of course of cotton. At a later period, in 1406, among the accounts of the church of Troyes, such mills appear as molins ä toile. The development of the trade in France must have been very rapid, for, as we have already noticed, that country was soon in a position to supply her neighbours as well as to provide for her own wants. And with the progress of manufacture in France that of the Netherlands also grew.
A study of the various water-marks has yielded some results in tracing the different channels in which the paper trade of different countries flowed; but a thorough and systematic collection and classification of them has yet to be accomplished. Experience also of the different kinds of paper, and a knowledge of the water-marks, aid the student in fixing nearly exact periods to undated documents. Rag paper of the 14th century may generally be recognized by its firm texture, its stoutness, and the large size of its wires. The water-marks are usually simple in design; and, being the result of the impress of thick wires, they are therefore strongly marked. In the course of the 15th century the texture gradually becomes finer and the wrater-marks more elaborate. While the old subjects of the latter are still continued in use, they are more neatly outlined, and, particularly in Italian paper, they are frequently enclosed in circles. The practice of inserting the full name of the maker in the water-mark came into fashion in the course of the 16th century. The variety of subjects of water-marks is most extensive. Animals, birds, fishes, heads, flowers, domestic and warlike implements, armorial bearings, &c, are found from the earliest times. Some of these, such as armorial bearings, and national, provincial, or personal cognizances, as the imperial crown, the crossed keys, or the cardinal's hat, can be attributed to particular countries or districts; and the wide dissemination of the paper bearing these marks in different countries serves to prove how large and international was the paper trade in the 14th and 15th centuries.
In the second half of the 14th century the use of paper for all literary purposes had become well established in all western Europe; and in the course of the 15th century it gradually superseded vellum. In MSS. of this latter period it is not unusual to find a mixture of vellum and paper, a vellum sheet forming the outside leaves of a quire while the rest are of paper.
With regard to the early use of paper in England, there is evidence that quite at the beginning of the 14th century it was a not uncommon material, particularly for registers and accounts. Under the year 1310, the records of Merton College, Oxford, show that paper was purchased "pro registro," which Prof. Sogers (Hist. Agricul. and Prices, i. p. 644) is of opinion was probably cotton paper of the same character as that of the Bordeaux customs register in the Public Record Office, which date from the first year of Edward II. The college register referred to, which was probably used for entering the books that the fellows borrowed from the library, has perished. There is, however, in the British Museum a paper MS. (Add. 31,223), written in England, of even earlier date than the one recorded in the Merton archives. This is a register of the hustings court of Lyme Regis, the entries in which commence in the year 1309. The material is cotton paper, with apparently an admixture of rag, the threads of which are visible, imbedded in the pulpsimilar to the kind which was used in Spain. It may indeed have been imported direct from that country or from Bordeaux; and a seaport town on the south coast of England is exactly the place where such early relics might be looked for. Professor Rogers also mentions an early specimen of paper made from rag in the archives of Merton College, on which is written a bill of the year 1332; and some leaves of water-marked paper of 1333 exist in the Harleian collection. Of a date only a few years later is the first of the registers of the King's Hall at Cambridge, a series of which, on paper, are preserved in the library of Trinity College. Of the middle of the 14th century also are many of the municipal books and records still to be found among the archives of ancient cities and towns. The knowledge, however, which we have of the history of paper-making in England is extremely scanty. The first maker whose name is known is one Tate, who is said to have set up a mill in Hertford early in the 16th century; and a German named Spielman had works at Dartford in 1588. But it is incredible that no paper was made in the country before the time of the Tudors. No doubt at first it was imported. But the comparatively cheap rates at which it was sold in the 15th century in inland towns, as well as in those nearer the coast, seem to afford ground for assuming that there was at that "time a native industry in this commodity, and that it was not altogether imported.
As far as the prices have been observed at which different kinds of paper were sold in England in the early period of its introduction, it has been found that in 1355-56 the price of a quire of small folio paper was 5d., both in Oxford and London. In the 15th century the average price seems to have ranged from 3d. to 4d. for the quire, and from 3s. 4d. to 4s. for the ream. At the beginning of the 16th century the price fell to 2d. or 3d. the quire, and to 3s. or 3s. 6d. the ream; but in the second half of the century, owing to the debasement of the coinage, it rose, in common with all other commodities, to nearly 4d. the quire, and to rather more than 5s. the ream. The relatively higher price of the ream in this last period, as compared with that of the quire, seems to imply a more extensive use of the material which enabled the trader to dispose of broken bulk more quickly than formerly, and so to sell by the quire at a comparatively cheap rate.
Brown paper appears in entries of 1570-71, and was sold in bundles at 2s. to 2s. 4d. Blotting paper is appar* ently of even earlier date, being mentioned under the year 1465. It was a coarse, grey, unsized paper, fragments of which have been found among the loaves of 15th century accounts, where it had been left after being used for blotting.
See Gerardi Meerman et doctorum virorum ad cum Epistolae atque Observations de Chartae vulgaris seu lineae origine, Hague, 1767 ; G. F. Wehrs, Vom Papier, Halle, 1789 ; M. Koops, Historical Account of the substances used to describe events and to convey ideas, from the earliest date to the Invention of Paper (London, 1801), in great part repeating Wehrsthe book is printed on paper manufactured from straw ; Ersch and Gruber, Allgem. Encyklopädie, art. "Papier," Leipsic, 1838; Sotzmann, "Ueber die ältere Papier-fabrikation," in Serapeum, Leipsic, 1846 ; W. Wattenbach, Das Schriftwesen im Mittelaller, Leipsic, 1875, pp. 114-123 ; J. E. T. Rogers, History of Agriculture and Prices in England, Oxford, 1866-82, passim. (E. M. T.)
MANUFACTURE OF PAPER.
Paper is a thin tissue composed of vegetable fibres (rarely of woollen fibres), resulting from their deposition on wire-cloth while suspended in water. At first it was entirely made by hand, but the invention in 1798 of the paper machine by Louis Robert, a clerk in the employment of Messrs Didot, of the celebrated Essonnes paper-mills, near Paris, gave a new impetus to the industry. The invention was introduced into England through the agency of Messrs Fourdrinier, who employed Bryan Donkin, the engineer, to assist in working it out; but, although they expended a large fortune in developing the invention, their enterprise resulted only in bankruptcy. Their first paper machine was erected in 1804 at Frogmoor Mill, near Boxmoor, Herts. In the United States it was not till 1820 that such a machine was started for the first time by Messrs T. Gilpin & Co., on the Brandywine. Since that period, machine-made paper has gradually supplanted that made by hand for all except special purposes, and has been brought to a high state of perfection by subsequent improvements in the machinery.
Paper may be divided into three main classes :writing paper, printing paper, and wrapping paper. The staple of which writing and printing paper is made is, in Britain, rags and esparto; in America a considerable quantity of wood pulp is used. Tbe staple of wrapping papers is old ropes and in some cases jute. The best writing and printing papers are still made, whether by hand or by machine, from rags.
Manufacture of Paper from Rags.The first process is the cutting and sorting of the rags, which is invariably done by women. The rag-cutter stands behind a knife about 14 inches long set in an oblique position in a table before her; the rags are cut into pieces about the size of the hand, and the linen pieces separated from the cotton, the various qualities being put into different receptacles. After being cut they are subjected to the action of the willow and duster, which knocks the loose dust off. The willow is composed of two conical cylinders, inside of which iron spikes project. In the interior of these cylinders an iron drum, also provided with spikes, revolves at about 300 revolutions per minute. The rags are fed into fhe first cylinder by a travelling felt, and dashed through from the one to the other by the action of the revolving drum, and from the second cylinder thrown forward into the duster. This consists of a large rectangular wooden case, in the interior of which an iron cage, covered with coarse wirecloth, revolves slowly at right angles to the willow. This cage is set at a slight incline, so that the rags which are thrown into it by the willow at one end slowly pass to the other, while the dust, &c, which has been disengaged by the action of the willow, falls through the wirecloth, and the dusted rags pass out at the other end, now ready for the boiler. The boiler is of different forms, revolving or stationary. The most usual is stationary. It consists of an upright cylinder of cast or malleable iron (fig. 1), about 8 feet in diameter by 6 feet deep, and fitted with a perforated false bottom, on which the rags rest. The boiler is further fitted with a filling door A at the top, and an emptying door B below. After being charged with rags, it is filled to about half its height with water; a sufficient quantity of caustic soda, varying according to the nature of the rags, is introduced; the door is then shut, and steam is admitted by a small pipe C which is contained in, and communicates at the foot with, a larger pipe D and causes a constant circulation of hot liquid, which is dispersed all over the boiler by striking against a hood E at the top. This is technically known as the " vomit." The rags are boiled in this solution of caustic soda for ten to twelve hours, when the steam is turned off and the liquid is discharged by the pipe G. After a subsequent washing with cold water in the boiler the lower door is opened and the boiled rags withdrawn into small trucks, and picked by women to remove impurities, such as india-rubber, &c.
The rags are now submitted to the action of the breaking engine (figs. 2 and 3). This is an oblong trough with rounded ends, and may be about 6 feet wide and 12 feet long by about 2 feet in depth, but the size varies greatly. It is partially divided in the centre by the midfeather A, and provided with a heavy iron roll B, fitted with knives technically called bars, which revolves at a high speed on the plate C, also furnished with knives. The engine is half filled with water and packed with the boiled rags. Water is introduced by the valve D, and is withdrawn by the washer E. The washer consists of a drum about 3 feet in diameter and 18 inches broad, covered with fine wire-cloth, and fitted inside with buckets shown by the dotted lines G. It is partially immersed in the pulp, and as it revolves discharges the water by the centre down the shoot H. The rags are allowed to remain in this washer, according to their cleanness, from one to two hours, and then the solution of chloride of lime by which they are bleached is introduced. After running mixed with this in the engine from one to two hours, the pulp is run down into large stone chests, where it is allowed to lie for twenty-four hours till it becomes perfectly white; it is then drained and pressed to remove the remaining bleaching solution as far as possible.
The bleached pulp is now removed to the beating engine, which differs but little from the washing engine except that in the roll of the beater there are three bars to the bunch, while in the washer there are only two to the bunch. Here the pulp is furnished in the engine with water as before, and washed till it is free from chloride of lime, or this may be neutralized by the use of a sulphite or hyposulphite of soda. The pulp is then submitted to the action of the beater roll for from four to six hours, the circular knives being allowed to revolve very near the plate, so as to draw out the fibres into a very fine state, while preserving their strength as far as possible. While the operation of " beating " is being proceeded with, the loading material, consisting of china clay or pearl white, is added. This is by no means to be viewed entirely as an adulteration, as it too generally is. No doubt to a certain extent it weakens the paper, but it is not added in hand-made papers, in which great strength is required. In writing papers for ordinary purposes, however, and in printing papers, the addition of mineral matter in moderation is of positive advantage, as it closes up the pores of the fibres and enables the paper to take a much better finish than it would otherwise do.
The next process is the sizing, to which all papers for writing and most of those for printing purposes are subjected. Sizing consists in the deposition on the fibres of a substance which is comparatively waterproof, and for engine sizing a mixture of resin soap treated with alum is employed. The resin soap is formed by dissolving resin in carbonate or caustic soda, allowing the mixture to cool, when the soap floats on the surface, and the mother-liquor, containing the excess of alkali, is run off. It is of considerable importance to get rid of this mother-liquor before using the soap, as it is of no use, and takes alum to neutralize it. The soap is now dissolved in water, and, in many mills where starch is used for stiffening purposes, mixed with the starch. This mixture is put into the beating engine in which the pulp is circulating, and when it is thoroughly incorporated with the pulp the solution of alum or sulphate of alumina is added. This forms a finely divided precipitate of resinate of alumina on the fibres. The pulp, after the sizing material is thoroughly incorporated with it, is now ready for colouring. Even to produce a pure white, colour must be added to the pulp. In general, for white papers, either cochineal and ultramarine blue are employed, or magenta and aniline blue. In all cases where permanence of colour is of importance, the former are to be preferred. For blue papers, ultramarine is generally used. Tinted papers are, as a rule, produced by the use of aniline colours. Coloured papers are produced by the use of various pigments.
The operation of beating the pulp is of the greatest importance, and too much care cannot be devoted to it. In America, where the mills are generally driven by water-power, the pulp is kept for a much longer time in the engine than in Great Britain, and this accounts to a considerable extent for the superiority of the American papers.
After the pulp is prepared in the beating engine it is run into the chests of the paper machine (figs. 4 and 5). These chests A are fitted with agitators, and from them the pulp is pumped into the supply-box B, which communicates with the sand-traps C by means of a regulating cock. Along with the pulp a certain amount of water is allowed to flow into the sand-trap, so as to thin it down sufficiently; in most cases the save-all water (see below) is employed for this purpose. The pulp flows backward and forward here in a shallow stream, so as to deposit any heavy impurities which it may contain. After issuing from the sand-traps it is delivered on to the strainers, which are made in many varieties, the most common being the revolving strainer D, shown on the plan. This is a rectangular trough into which the pulp flows. In the centre of this the strainer, rectangular in form, composed of four sets of brass plates bolted to a frame in which very fine slits are cut, revolves slowly. The size of this is about 7 feet by 2 feet. The pulp is made to flow from the outside through the slits to the inside of the strainer by means of suction produced by bellows or disks in the interior of the plates, and is discharged by the pipe E into a box from which it flows on to the apron F, which is placed on the top of the breast roll. The apron is made of a piece of moleskin or india-rubber cloth the full width of the wire, and prevents the pulp from running away down the back of the wire. It covers the wire for 12 to 18 inches at the beginning. The wire consists of an endless sheet of fine wirecloth (about 66 wires per square inch) which stretches from the breast roll G to the couch roll H, returning underneath by the leading rolls I. Underneath the first portion of the wire are the tube rolls K, and farther along are the vacuum boxes L, L. These communicate by pipes with the vacuum pumps M. As the wire revolves in the direction shown in fig. 4 the pulp is allowed to flow from the strainer and spreads itself out in a thin film, covering the surface of the wirecloth. It is prevented from flowing over the sides of the wire by the deckle straps, endless india-rubber straps N. Part of the water runs off through the meshes of the wire by gravitation, and the rest is removed through the suction boxes L by the vacuum pumps M. Stretching along under the wire from the breast roll to the first suction box is the save-all, a shallow trough into which the water which passes through the wire falls. The contents of this box flow into a cistern at the back of the machine into which the vacuum pumps also discharge their water; and from this cistern the water is pumped into a service box and used instead of fresh water for mixing with the pulp as it flows on to the sand-trap. There is a considerable saving in this, as the fine fibre, size, &c, contained by the water passing through the wire is all in this way recovered. Between the first and second suction box the dandy roll, a skeleton roll covered with wirecloth, revolves on the top of the pulp. By means of raised wires on it in the form desired the paper is rendered thinner at these parts and a water-mark is produced. In order to secure regularity in the layer of pulp, as also to increase the strength of the paper, a lateral motion is communicated to the wire by the shake O. The half-dried pulp now passes between the couch rolls, where it receives the first pressure. The under couch roll generally consists of a brass shell fixed by iron rings to a spindle; the top roll may be either similar to the lower one or made of mahogany, and is always covered with a felt jacket. Pressure is applied to the ends of the top roll by means of levers and weights. From these the sheet of partially dried pulp is carried by endless felts through the first and second press rolls R and S. The press rolls are either made of solid iron, or may with advantage have a brass shell shrunk on. Having been freed by these from a great part of its water, the web of paper is carried over the steam-heated cylinders T, T. The first two cylinders are generally bare, and the heat applied to these is gentle ; in the case of the others, the paper is kept close to the cylinder by means of endless felts. The web then passes through the intermediate rolls U in a half-dried state, over three more cylinders and the calenders V. These are heavy iron rollers heated by steam internally and polished externally. Their object is to communicate a gloss to the web of paper. It is then wound up on the reel W, and these reels when filled with paper are removed as required to the paper cutter. In cases where the paper is to be sized with gelatin after leaving the machine, it is wound up rough.
A modification of the Fourdrinier machine, suitable for the manufacture of thin papers and those which only require to be smooth on one side, is shown in fig. 6. It consists of an ordinary paper machine as far as the couch rolls A, A. From these the paper is carried backwards on the top of the endless felt B till it comes in contact with the large steam-heated cylinder C at d. Here it adheres to the cylinder, being pressed against it at the same time by the press roll E. The paper then continues round the surface of the cylinder, and is wound up dry on reels at G. The felt washer H is a box filled with water through which the felt passes as it travels. After this the paper is cut or glazed in the usual way.
At this stage papers which require to be hard-sized, principally the better sorts of writing papers, are sized with gelatin or "tub-sized." This is done occasionally by passing the sheets separately through a trough containing a strong solution of gelatin, and afterwards hanging them up to dry in the same way as hand-made papers, but in general the paper is sized and dried in the web after leaving the paper machine. For this purpose a sizing and drying machine is used (fig. 7). The web of paper to be sized is shown at A. From this it is passed through a trough B containing a strong solution of gelatin into which a certain amount of alum is introduced; after passing through this by means of the size rolls C, C, it is passed through the press rolls D, which squeeze out the superfluous size from it, and rewound on a reel at E to allow the size time to set. The web is then transferred to the drying machine at G, and passed over a series of spar drums H, H at a slow speed. These drums are fitted round their circumference with wooden spars I on which the paper rests, while a current of heated air from pipes underneath ascends through them and is driven against the inner surface of the paper by the fanners K, K, which revolve at a high speed. The great thing to be studied in this operation is to keep as low a temperature as possible, not above 80° Fahr. There may be any number of these drums; the larger the number the lower the temperature at which the paper can be dried. In some mills as many as two hundred of them go to a drier. After being wound up at the end of the drier the paper is ready for cutting in the ordinary way.
The ordinary paper cutter (fig. 8) cuts from six to eight webs at once. The webs to be cut may be seen on the drawing at a, a. The webs of paper from these are led between the leading rolls b, b through the feeding rolls c, c. These, by means of the change pulley d, are driven at such a speed that they feed the paper to the revolving knife at the exact speed necessary to give the length of sheet required. After passing the feeding rolls the paper passes on to the slitting knives e. These are circular revolving knives which slit the paper into the width required. From these the webs pass through the drawing rolls/,/tothe revolving knife g, which, coming down with a sheer ^ against the dead knife g', cuts them r~ crosswise into the required length of sheet. The size of the sheet may be made longer or shorter, by altering the size of the expanding pulley h and the change pulley d. After being cut, the sheets of paper are caught by the endless felt i and carried forward to the table h, where they are arranged by boys.
Another form of paper cutter which is employed for water-marked papers (see paper machine) is the single-sheet cutter, fig 9. In this cutter only one web of paper is cut at a time, but it can be adjusted to a much greater degree of nicety than the revolving cutter. After passing through the slitting knives A, which are in all respects similar to those in the revolving cutter, the paper is carried over the measuring drum C, which, by a crank arrangement DE receives an oscillating motion and can be adjusted to draw the exact quantity of paper forward for the length of sheet required. The paper is kept fast on the drum by the gripper rolls F, F, arranged so as to rise and fall as the drum oscillates, while the dancing roll B keeps the web at a uniform tension. The paper is cut into sheets by the knife I, connected with cranks and links G, and supported by the link rods H, H working horizontally with a swinging motion against the dead knife K. At the same time the clamp L holds the web in position. The sheet to be cut may be seen hanging down at the dotted line M. The sheets are then caught by girls and dressed up in the usual way. This cutter requires a great deal of attention, and is only used when extreme accuracy is required.
Calenders.If it is desired to give the paper a higher gloss than can be done on the calenders of the paper machine, or where, as in the case of papers sized with gelatin, these must be glazed after leaving the paper machine, it is done by the use either of the plate or roll calender. (1) The plate calender (fig. 10) is composed of a framework A, in which are set two highly polished rolls of solid iron B, B, with a space of about f inch intervening. By means of levers and weights pressure can be applied to the top roll. The paper to be glazed is placed sheet by sheet between copper or zinc plates, till a bundle considerably thicker than the space between the rolls is made. This bundle is then passed backward and forward between the rollers, under considerable pressure, and the polished surface of the plates communicates a gloss to the paper.
(2) In America a calender of different construction is employed (fig. 11). In it a perpendicular series of highly polished iron and compressed cotton or paper rolls are placed alternately between frames, and revolve at a high speed. The sheets of paper are one by one introduced by an attendant, who sits in a convenient position near the top of the. calender, under the tapes a, which, running against the roll A, convey the sheet to the next roll B. After passing under the roll A, the paper has a tendency to adhere to the metal surface; this is overcome by a sharp-pointed knife b placed against it, so that the sheet is again caught by the next set of tapes, and so on till it completes its course, and comes out at the foot of the calender. If a still higher glaze is required, the sheets are passed through a second time. A much larger quantity of paper can be glazed in the same time by one of these calenders than by the so-called plate calender, and at a greatly smaller outlay for wages, but the surface acquired by the paper wants the peculiar gloss communicated to it by the latter, and for the higher grades of paper this still retains its position in Great Britain.
After being cut, and, if necessary, calendered, the paper is sorted, that is to say, it is examined sheet by sheet, and all torn or soiled sheets are taken out. It is then counted into quires and reams, each quire containing twenty-four sheets, and each ream twenty quires.
Hand-Made Paper.So far the preparation of pulp, whether for paper making by hand or by machine, is identical, the chief difference being that only the most expensive drawing and writing papers are now manufactured by hand, and for this purpose only the finest qualities of rags are used. The process will be best understood by reference to the drawing (fig. 12). The pulp, after being prepared in the beating engine as above described, is run into large chests from which the vat is supplied. Before reaching this it is strained as on the paper machine. Hand-made paper is made by means of a mould (fig. 13). This consists of a framework of fine wirecloth with a deckle " or movable frame of wood all round it, to keep the pulp from running off. Nearly all hand-made papers have also a water-mark (W. King in this instance), which is produced by wires representing these letters being raised above the rest of the mould. Hence the paper in these parts is thinner, and the letters can be read on holding the sheet up to the light.
The sheet of paper is formed in the following way. The vatman, fig. 12, takes up enough pulp on the mould to fill the deckle. He runs the stuff evenly over the mould from the foreside to the back, throwing back any pulp
which may be superfluous, and then gives the mould the " shake," a gentle shake both along and across the mould, causing the water to run through the wirecloth while the pulp which forms the sheet of paper stays on the top. The vatman then brings the mould to the stay ; it is placed by the coucher on an inclined elbow, where some more water drains away, and he afterwards turns it over on the felt, leaving the sheet of paper on the felt. When the
proper number of sheets of paper, with a felt between each, has been placed in the pile called a " post," it is taken to the press, and a great quantity of the water is pressed out, leaving the sheets of paper sufficiently dry to be handled by the " layer," who places them in packs, one sheet above the other, and after being parted sheet from sheet they are repressed. After this the paper is hung in a drying loft on cow-hair ropes in spurs of three to five sheets thick until dry. It is then sized by passing the spurs through a strong solution of gelatin contained in a long trough. The paper passes along on an endless felt, and is freed from superfluous size by press rolls at the end of the trough. It is then parted again to prevent the sheets from sticking together, and is again dried at a temperature of 70° to 80° Fahr. After being picked and then glazed between plates, it is sorted and finished in the same way as other paper, but with much greater care.
It will readily be understood that the expense of manufacturing paper in this way is very much greater than by machinery; but the gain in strength, partly owing to the time allowed to the fibres to knit together, and partly to the free expansion permitted them in drying, still maintains a steady demand for this class of paper, and probably 60 to 70 tons per week are made in Great Britain at present.
In America, papers of great strength are manufactured by machinery, and not much hand-made paper is made.
Manufacture from other Substances than Rags.Although the better varieties of both writing and printing paper are still manufactured from rags, the supply of these has been found altogether insufficient to supply the increasing-demand for paper, and other fibres have to a great extent been substituted for the cheaper classes of paper. First among these is ESPARTO (q.v.). The treatment of esparto does not greatly vary from that of rags. On arrival at the mill the grass is sorted ; that is to say, it is spread out in bunches on a table with a wire gauze cover, and these are shaken to remove the dust, while the roots and weeds are removed by picking. This is technically known as dry picking. In some mills this process is done mechanically by aid of a duster, which removes dust and other heavy impurities from the esparto, but it must then be picked in the wet state after boiling. The boiling is done in the same way as rags, but with a larger proportion of caustic soda. Mr Thomas Routledge, the introducer of esparto, specifies 10 per cent, real caustic soda, but with improved forms of boilers such as Roeckner's or Sinclair's, operating at 40 to 50 ft> pressure, a considerable saving on this amount of alkali may be effected. The subsequent treatment of esparto is similar to that for rags; it is again " wet-picked " after boiling, then washed and bleached, a much larger quantity of chloride of lime being required than in the case of rags. It can be treated either alone or mixed with rags, and forms a very mellow bulky paper admirably adapted for printing purposes.
A considerable quantity of straw is used both in Britain and in America for paper-making. In general it is mixed either with rags or with esparto, being of too brittle a nature when bleached to make into paper alone. It is generally dusted after arrival at the mill, in many cases cut into chaff before the boiling operation, so as to allow the soda freer access to the fibres, and boiled under high pressure with considerable quantities of caustic soda up to 15 per cent, of real caustic. It is then washed either separately or along with esparto, and bleached in the ordinary way. As at present treated, the yield averaging only 33 to 40 per cent., straw will not come into general use, except in cases where the raw material can be bought on unusually advantageous terms. There is no doubt that, in this case especially, a more rational method of extracting the cellulose than by boiling under high pressure with u large amount of caustic soda is most desirable, for, many of the fibres of the straw being extremely fine, these are to a considerable extent actually dissolved by the soda, and, whereas theoretically straw with 15 per cent, moisture ought to produce 45 per cent, cellulose, by the soda treatment not more than 33 per cent, are obtained, where a good white colour is desired.
The only other fibre which has seriously threatened to compete with rags or esparto is wood. From the fact that the supply of this raw material is apparently inexhaustible, a great deal of attention has been paid to methods for reducing it to a fibre capable of being made into paper. These divide themselves into two(1) mechanical and (2) chemical treatment. (1) The wood generally selected for this purpose is white pine or poplar. It is cut into slabs of convenient size, which are then pressed against the face of a mill-stone revolving at a high speed, while a flow of water conveys the fibres of wood away as they are separated. They are then sieved according to fineness, collected, and pressed into pulp or half stuff, which is used for admixture in inferior papers, or even, in some cases, for making paper. By this means of treatment, however, the wood is not split up into its ultimate fibres, but is left with all the incrusting matter attached, and the pulp and paper so obtained are only fitted for the commonest purposes. (2) Many efforts have been made with the view of preparing wood chemically, so that the resulting fibre might be introduced into fine papers, and latterly with considerable success. In the earlier processes, patented by Houghton and Sinclair, wood was boiled with about 20 per cent, real caustic soda under a pressure of from 10 to 14 atmospheres. By this means, with certain improvements in detail, dictated by experience, so-called chemical wood pulp is prepared in large quantities on the Continent, and is imported as. pulp into England to a considerable extent. In America this process has been extensively adopted. While pulp of very fair quality is prepared in this way suitable for papers where a perfectly white colour is not required, there is no room for doubt that the action of the caustic soda solution at the extreme temperature which a pressure of upwards of 10 atmospheres involves, leads to a certain extent to a degradation and consequent weakening and browning of the fibres, and a great deal of work has been directed to the surmounting of this difficulty. The result has been a series of patents, all containing the same principle, namely, the treating the wood with a chemical agent which should prevent oxidation and subsequent degradation of the fibres from taking place. Such patents are those of Mitscherlich and Francke (bisulphite of lime), Ekman and Graham (bisulphite of magnesia). While these all contain a common principle, they differ in detail, as to pressure, blowing off of the sulphurous acid gas, <fec, but they all present a very marked resemblance to Tilghmann's expired patent, 1866, No. 2924. The pulp produced by all those processes is of excellent quality; and, according to the statements of the patentees, it can be prepared at a cost greatly lower than by the soda process. The strength of the fibre is maintained unimpaired even after bleaching, and white paper made solely from such pulp is in every respect superior to that manufactured solely from pulp prepared by boiling with caustic soda.
Dr Mitscherlich's process has been extensively adopted in Germany, and there seems little doubt that these processes will in time supplant the use of soda in the case of wood. The great objection to them all is that, as they all depend on the use of bisulphite, which, being an acid salt, cannot be worked in an iron boiler, the boiler must be lined with lead ; and great difficulty has been encountered in keeping the lead lining of the boiler in repair. This is a difficulty, however, which will probably be overcome with further experience. The objection to cellulose prepared from wood by all the acid processes is that it is not pure, but a considerable quantity of incrusting matter is left in the fibre, and hence the paper manufactured from it solely is harsh in character and very transparent; to procure a pure cellulose, it must be exhausted in an alkaline solution subsequent to the treatment with acid.
The waste of jute is largely used in the manufacture of coloured papers, but it has not hitherto been found possible to thoroughly bleach this fibre without at the same time destroying its strength.
A long series of experiments, with a view to the introduction of bamboo fibre for paper making, has been undertaken by Mr Thomas Routledge, the well-known introducer of esparto, who recommends the employment of the young shoots. It may well be doubted whether the bamboo has any chance as a competitor against the new processes for preparing wood.
A host of other fibres have been tried from time to time, such as dis grass from the north coast of Africa, the leaves of the dwarf palm, sugar-cane refuse, the stalks of the hop plant, nettles, peat, Phormium tenax from New Zealand, with many others (see Dr Hugo Müller's Pflanzenfaser), but none with such success as to call for notice here.
Soda Recovery.In the preparation of esparto wood, and other raw material for manufacture into paper, large quantities of caustic soda are employed, and, as the resulting liquid after boiling the fibre in caustic soda solution is strongly alkaline and dark-coloured, it is very desirable to keep it out of the rivers. In order to effect this it is in many mills evaporated, and the soda it contains recovered, and, after causticizing, reused. Many forms of evaporator have been proposed, and of late years great improvement has been made in their construction. Probably the best form is the Porion evaporator (tig. 14). This consists of an evaporating chamber A, on the floor of which a fewr inches of the liquid to be evaporated rest. By the action of fanners B, B revolving at a high speed and dipping into the liquid, it is thrown up in a fine spray through which the heated gases pass to the chimney. After being concentrated in the evaporating chamber the liquid flows into the incinerating furnaces C,C, where the remaining water is driven off by the heat of the fire D, and the mass afterwards ignited to drive off the carbonaceous matter. A considerable feature in this evaporator is Menzies and Davis's patent smell chamber E, a chamber filled with masonry in which the strongly-smelling gases from the incinerating furnace are allowed to remain at a red heat for a short time. After being recovered, the soda, in the form of crude carbonate, is lixiviated and recausticized by boiling with milk of lime.
Sizes of Paper. The following are the ordinary sizes :
== TABLE ==
British Paper Trade. The comparative returns of the I the Board of Trade (Great Britain) for the years 1882 and 1883 amounts and values of the imports and exports published by ' are as follows :
== TABLE ==
American Paper Trade.At the end of 1882 there were in the United States 1051 paper mills (1004 the previous year). Of this number 1018 are in active operation. These mills are owned and worked by 823 firms or establishments, an increase of 23 over the previous year. Twenty-three mills were abandoned during 1882, while 17 were destroyed by fire ; 36 were in course of construction, and 68 new mills went into full work during 1882. This number is composed of a few mills reconstructed after fire, and 39 new establishments erected during 1882. The mills represent almost every variety of paper and pulp, and have an estimated daily capacity of 300 tons. Altogether there were in 1883 44 more mills in operation than in 1882. At the beginning of 1884 36 new mills were being constructed and may be expected to be at work during the year. Every variety of paper is extensively manufactured in the United States with the exception of hand-made, but of late years attention has been devoted to this also, English plant and labour having been imported for the purpose, and hand-made papers are now regularly produced in small quantities.
Bibliography.Herring, Paper and Papermaking; Piette, Manuel de la Papeterie, 1861 ; Dropisch, Die Papiermaschine, 1878 ; G. Planche, L'Industrie de la Papeterie, 1853; L. Müller, Fabrikation des Papiers, 1855 ; Proteaux, On the Manufacture of Paper and Boards, 1866 ; Hugo Müller, Pflanzenfaser, 1877 ; C. Hofmann, Manufacture of Paper. 1873; T. Routledge, Bamboo considered as a Papermaking Material, 1875 ; Papermakers' Monthly Journal, London ; Paper Trade Journal, New York ; Papier-Zeitung, Berlin. (R. C. M.)
217-1 A few of the earliest dated examples may be instanced. The Gharibu 'l-Hadith, a treatise on the rare and curious words in the sayings of Mohammed and his companions, written in the year 866, is probably one of the oldest paper MSS. in existence (Pal. Soc., Orient. Ser., pl. 6). It is preserved in the University Library of Leyden. A treatise by an Arabian physician on the nourishment of the different members of the body, of the year 960, is the oldest dated Arabic MS. on paper in the British Museum (Or. MS. 2600 ; Pal. Soc., pl. 96). The Bodleian Library possesses a MS. of the Diwanu 'l-Adab, a grammatical work of 974 A.D., of particular interest as having been written at Samarkand on paper presumably made at that seat of the first Arab manufacture (Pal. Soc., pl. 60). Other early examples are a volume of poems written at Baghdad, 990 A.D., now at Leipsic, and the Gospel of St Luke, 993 A.D., in the Vatican Library (Pal. Soc., pls. 7, 21). In the great collection of Syriac MSS. which were obtained from the Nitrian desert in Egypt, and are now in the British Museum, there are many volumes written on cotton paper of the 10th century. The two oldest dated examples, however, are not earlier than 1075 and I084 A.D.
221-1 Another form of heating engine which is finding great favour is the Umpherston engine, which differs little from the ordinary heater, except in having, instead of a midfeather, a passage under the roll by which the pulp circulates. It is claimed for it that one capable of preparing 10 cwts. of paper does not occupy more floor area than an ordinary beater for 3 cwts. The pulp is also said to travel more freely, and does not lodge about the corners as in the ordinary engine.
225-1 The imports, which in 1863 amounted to 18,000 tons, had risen to 100,000 tons in 1870, and in 1883 reached 206,000 tons.
The above article was written by two authors:
-- History of Paper
Sir Edward Maunde Thompson, K.C.B., D.C.L., LL.D.; Director and Principal Librarian, British Museum; Keeper of the MSS. and Egerton Librarian, 1878; Sandars Reader in Bibliography, Cambridge, 1895-96; editor of Chronicon Angliae; edited Letters of Humphrey Prideaux, Diary of Richard Cocks in Japan, 1615-1622, etc.; joint editor of publications of Palaeographical Society, and of the Facsimile of the Laurentian Sophocles.
-- Manufacture of Paper
R. C. Menzies; Inveresk Paper Mills, Musselburgh.