---------------------------------------- ---------------------------- ,transcriber's ,notes ,passages in italics are indicated by italics4 ,passages in bold are indicated by bold4 ,passages in small caps are shown in title case without explicit indication4 ,subscripted characters are indicated by subscript4 ,superscripted characters are indicated by x 7x is a single character74 ,,oe is the latin ,,oe ligature4 ,a list of inconsistencies and corrections is at the end of the text4 ---------------------------------------- ---------------------------- ,,the ,,manufacture ,,of ,,paper ,,by ,r4 ,w4 ,,sindall1 ,f4,c4,s4 ,,consulting ,,chemist ,,to ,,the ,,wood ,,pulp ,,and ,,paper ,,trades2 ,,lecturer ,,on ,,paper-,,making ,,for ,,the ,,hertfordshire ,,county ,,council1 ,,the ,,bucks ,,county ,,council1 ,,the ,,printing ,,and ,,stationery ,,trades ,,at ,,exeter ,,hall1 #aijc-d1 ,,the ,,institute ,,of ,,printers2 ,,technical ,,adviser ,,to ,,the ,,government ,,of ,,india1 #aije ,,author ,,of ,,paper ,,technology1 ,,the ,,sampling ,,of ,,wood ,,pulp ,,joint ,,author ,,of ,,the ,c4,b4,s4 ,,units1 ,,or ,,standards ,,of ,,paper ,,testing1 ,,the ,,applications ,,of ,,wood ,,pulp1 ,,etc4 ,,with ,,illustrations1 ,,and ,a ,,bibliography ,,of ,,works ,,relating ,,to ,,cellulose ,,and ,,paper-,,making ,illustration ,,new ,,york ,d4 ,,van ,,nostrand ,,company #bc ,,murray ,,and #bg ,,warren ,,streets #aijh ,,preface ,paper-making1 in common with many other industries1 is one in which both engineering and chemistry play important parts4 ,unfortunately the functions of the engineer and chemist are generally regarded as independent of one another1 so that the chemist is only called in by the engineer when efforts along the lines of mechanical improvement have failed1 and vice versa4 ,it is impossible1 however1 to draw a hard and fast line1 and the best results in the art of paper-making are only possible when the manufacturer appreciates the fact that the skill of both is essential to progress and commercial success4 ,in the present elementary text-book it is only proposed to give an outline of the various stages of manufacture and to indicate some of the improvements made during recent years4 ,the author begs to acknowledge his indebtedness to manufacturers and others who have given permission for the use of illustrations4 ,,contents ,,page ,,preface v ,,list ,,of ,,illustrations ix ,,chapter ,i4 ,,historical ,,notice #a ,,ii4 ,,cellulose ,,and ,,paper-,,making ,,fibres #bj ,,iii4 ,,the ,,manufacture ,,of ,,paper ,,from ,,rags #dg ,,iv4 ,,esparto ,,and ,,straw #gb ,v4 ,,wood ,,pulp1 ,,and ,,wood ,,pulp ,,papers #ie ,,vi4 ,,brown ,,papers ,,and ,,boards #abf ,,vii4 ,,special ,,kinds ,,of ,,paper #acg ,,viii4 ,,chemicals ,,used ,,in ,,paper-,,making #aec ,,ix4 ,,the ,,process ,,of ,,beating #age ,x4 ,,the ,,dyeing ,,and ,,colouring ,,of ,,paper ,,pulp #aii ,,xi4 ,,paper ,,mill ,,machinery #bad ,,xii4 ,,the ,,deterioration ,,of ,,paper #bbi ,,xiii4 ,,bibliography #bec ,,index #bgc ,,list ,,of ,,illustrations ,,fig4 ,,page #a4 ,,sheet ,,of ,,papyrus1 ,,showing ,,the ,,layers ,,crossing ,,one ,,another #c #b4 ,,an ,,early ,,paper ,,mill 7,,from ,,kulturhistorischen ,,bilderbuch1 ,a4,d4 #aefd7 #aj #c4 ,,the ,,paper ,,mill ,,of ,,ulman ,,stromer1 ,a4,d4 #acij 7,,supposed ,,to ,,be ,,the ,,oldest ,,known ,,drawing ,,of ,a ,,paper ,,mill7 #ab #d4 ,,the ,,first ,,paper ,,machine1 ,a4,d4 #ahjb4 ,,plan ,,and ,,elevation #ag #e4 ,,the ,,improved ,,paper ,,machine ,,of ,a4,d4 #ahaj #ah #f4 ,a ,,rag ,,sorting ,,house #dg #g4 ,a ,,rag ,,duster #di #h4 ,a ,,rag ,,cutter #ej #i4 ,,interior ,,of ,,paper ,,mill ,,for ,,hand-,,made ,,paper 7,r4 ,,batchelor ,,sons7 #ea #aj4 ,,view ,,of ,a ,,rag ,,boiler1 ,,showing ,,connections #eb #aa4 ,a ,,breaking ,,and ,,washing ,,engine #ed #ab4 ,,oettel ,,and ,,haas' ,,apparatus ,,for ,,the ,,manufacture ,,of ,,electrolytic ,,bleach ,,liquor #eh #ac4 ,,the ,,hollander ,,beating ,,engine #ei #ad4 ,,the ,,hand ,,mould1 ,,showing ,,frame ,,and ,,deckle #fa #ae4 ,,apparatus ,,for ,,sizing ,,paper ,,in ,,continuous ,,rolls #fc #af4 ,a ,,supercalender #fe #ag4 ,,the ,,first ,,watermark ,,in ,,paper #fg #ah4 ,,cotton #fi #ai4 ,,linen #gj #bj4 ,,an ,,esparto ,,duster #gd #ba4 ,,sinclair',s ,,vomiting ,,esparto ,,boiler #ge #bb4 ,a ,,porion ,,evaporator #gf #bc4 ,,scott',s ,,multiple ,,effect ,,evaporator #gi #bd4 ,a ,,presse-,p,,te ,,for ,,esparto ,,pulp #he #be4 ,,esparto ,,pulp #hh #bf4 ,a ,,cylindrical ,,digester ,,for ,,boiling ,,fibre #hi #bg4 ,,straw #ic #bh4 ,a ,,pair ,,of ,,barkers ,,for ,,removing ,,bark ,,from ,,logs ,,of ,,wood #ih #bi4 ,,view ,,of ,,horizontal ,,grinder 7,a71 ,,with ,,section 7,b7 #ii #cj4 ,a ,,vertical ,,grinder ,,for ,,making ,,hot ,,ground ,,mechanical ,,wood ,,pulp #aja #ca4 ,,centrifugal ,,screen ,,for ,,wood ,,pulp #ajb #cb4 ,,section ,,of ,,centrifugal ,,screen ,,for ,,wood ,,pulp #ajc #cc4 ,,wood ,,pulp ,,digester1 ,,partly ,,in ,,elevation1 ,,partly ,,in ,,section #ajf #cd4 ,,view ,,of ,,ordinary ,,sulphur-,,burning ,,ovens #ajh #ce4 ,,spruce ,,wood ,,pulp #aad #cf4 ,,mechanical ,,wood ,,pulp #aae #cg4 ,,the ,,screens ,,for ,,removing ,,coarse ,,fibres ,,from ,,beaten ,,pulp #aah #ch4 ,,the ,,paper ,,machine 7,,wet ,,end ,,showing ,,wire7 #aai #ci4 ,,paper ,,machine ,,showing ,,wire1 ,,press ,,rolls1 ,,and ,,drying ,,cylinders #abc #dj4 ,,single ,,cylinder ,,or ,,yankee ,,machine #acj #da4 ,,section ,,of ,,wet ,,press1 ,,or ,,board ,,machine #aca #db4 ,,double ,,cylinder ,,board ,,machine #acc #dc4 ,,apparatus ,,for ,,making ,,parchment ,,paper #ach #dd4 ,,general ,,arrangement ,,of ,,plant ,,for ,,making ,,art ,,paper #adc #de4 ,,sectional ,,elevation ,,of ,,coating ,,plant #add #df4 ,,cotton ,,pulp ,,beaten #h ,,hours #agi #dg4 ,,cotton ,,pulp ,,beaten #cg ,,hours #ahj #dh4 ,,plan ,,and ,,sectional ,,elevation ,,of ,a ,,hollander #ahe #di4 ,,beating ,,engine ,,with ,,four ,,beater ,,rolls #ahf #ej4 ,,umpherston ,,beater #ahh #ea4 ,,section ,,of ,,umpherston ,,beating ,,engine #ahi #eb4 ,,nugent',s ,,beating ,,engine ,,with ,,paddles ,,for ,,circulating ,,the ,,pulp #aij #ec4 ,a ,,tower ,,beating ,,engine ,,with ,,centrifugal ,,pump ,,for ,,circulating ,,pulp #aia #ed4 ,,working ,,parts ,,of ,a ,,modern ,,refining ,,engine #aib #ee4 ,,conventional ,,diagram ,,of ,a ,,water ,,softening ,,plant #baf #ef4 ,,an ,,enclosed ,,steam ,,engine #bbj #eg4 ,,an ,,electrically ,,driven ,,paper ,,machine #bbb #eh4 ,,diagram ,,of ,,the ,,eibel ,,process #bbc ,,the ,,manufacture ,,of ,,paper ,,chapter ,i ,,historical ,,notice ,history4--,the art of paper-making is undoubtedly one of the most important industries of the present day4 ,the study of its development from the early bygone ages when men were compelled to find some means for recording important events and transactions is both interesting and instructive1 so that a short summary of the known facts relating to the history of paper may well serve as an introduction to an account of the manufacture and use of this indispensable article4 ,tradition4--,the early races of mankind contented themselves with keeping alive the memory of great achievements by means of tradition4 ,valiant deeds were further commemorated by the planting of trees1 the setting up of heaps of stones1 and the erection of clumsy monuments4 ,stone ,obelisks4--,the possibility of obtaining greater accuracy by carving the rude hieroglyphics of men and animals1 birds and plants1 soon suggested itself as an obvious improvement2 and as early as ,b4,c4 #djjj the first records which conveyed any meaning to later ages were faithfully inscribed1 and for the most part consigned to the care of the priests4 ,clay ,tablets4--,the ordinary transactions of daily life1 the writings of literary and scientific men1 and all that was worthy of note in the history of such nations as ,chaldea and ,assyria have come down to us also1 inscribed on clay tablets1 which were rendered durable by careful baking4 ,on a tablet of clay1 one of the earliest specimens of writing in existence1 now preserved in the ,british ,museum1 is recorded a proposal of marriage1 written about ,b4,c4 #aecj1 from one of the ,pharaohs1 asking for the hand of the daughter of a ,babylonian king4 ,waxed ,boards4--,bone1 ivory1 plates of metal1 lead1 gold1 and brass1 were freely used1 and at an early period wooden boards covered with wax were devised by the ,romans4 ,in fact1 any material having a soft impressionable surface was speedily adopted as a medium for the permanent expression of men's fancy1 so that it is not strange to find instances of documents written on such curious substances as animal skins1 hides1 dried intestines1 and leather4 ,the works of ,homer1 preserved in one of the ,egyptian libraries in the days of ,ptolemus ,philadelphus1 were said to have been written in letters of gold on the skins of serpents4 ,leaves1 ,bark4--,the first actual advance in the direction of paper1 as commonly understood1 was made when the leaves and bark of trees were utilised4 ,the latter especially came speedily into favour1 and the extensive use of the inner bark 7liber7 made rapid headway4 ,manuscripts and documents written on this liber are to be found in many museums4 ,papyrus4--,the discovery of the wonderful properties of the ,egyptian papyrus was a great step in developing the art of paper-making4 ,the date of this discovery is very uncertain1 but one of the earliest references is to be found in the works of ,pliny1 where mention is made of the writings of ,numa1 who lived about ,b4,c4 #fgj4 ,this celebrated plant had long been noted for its value in the manufacture of mats1 cordage1 and wearing apparel1 but its fame rests upon its utility in quite a different direction1 namely1 for conveying to posterity the written records of those early days which have proved a source of unending interest to antiquaries4 ,illustration3 ,,fig4 #a4--,sheet of ,papyrus1 showing the layers crossing one another 7,evans74 ,the ,egyptian papyrus was made from the fine layers of fibrous matter surrounding the parent stem4 ,these layers were removed by means of a sharp tool1 spread out on a board1 moistened with some gummy water1 and then covered with similar layers placed over them crosswise4 ,the sheets so produced were pressed1 dried1 and polished with a piece of ivory or a smooth stone4 ,long rolls of papyrus were formed by pasting several sheets together to give what was termed a volumen4 ,roman ,papyri4--,the ,romans improved the process of manufacture1 and were able to produce a variety of papers1 to which they gave different names1 such as ,charta hieratica 7holy paper1 used by priests71 ,charta ,fanniana 7a superior paper made by ,fannius71 ,charta emporetica 7shop or wrapping paper71 ,charta ,saitica 7after the city of ,sais71 etc4 ,the papyrus must have been used in great quantities for this purpose1 since recent explorations in ,eastern countries have brought to light enormous finds of papyri in a wonderful state of preservation4 ,in #agec1 when the ruins of ,herculaneum were unearthed1 no less than #a1hjj rolls were discovered4 ,during the last ten years huge quantities have been brought to ,england4 ,parchment4--,parchment succeeded papyrus as an excellent writing material1 being devised as a substitute for the latter by the inhabitants of ,pergamus on account of the prohibited exportation of ,egyptian papyrus4 ,for many centuries parchment held a foremost place amongst the available materials serving the purpose of paper1 and even to-day it is used for important legal documents4 ,this parchment was made from the skins of sheep and goats1 which were first steeped in lime pits1 and then scraped4 ,by the plentiful use of chalk and pumice stone the colour and surface of the parchment were greatly enhanced4 ,vellum1 prepared in a similar manner from the skins of calves1 was also extensively employed as a writing material1 and was probably the first material used for binding books4 ,until comparatively recent times the term parchment comprehended vellum1 but the latter substance is much superior to that manufactured from sheep and goat skins4 ,paper4--,the ,chinese are now generally credited with the art of making paper of the kind most familiar to us1 that is from fibrous material first reduced to the condition of pulp4 ,materials such as strips of bark1 leaves1 and papyrus cannot of course be included in a definition like this1 which one writer has condensed into the phrase ,paper is an aqueous deposit of vegetable fibre4 ,a4,d4 #aje4--,the earliest reference to the manufacture of paper is to be found in the ,chinese ,encyclopdia1 wherein it is stated that ,ts'ai-,lun1 a native of ,kuei-yang1 entered the service of the ,emperor ,ho-,ti in ,a4,d4 #ge1 and devoting his leisure hours to study1 suggested the use of silk and ink as a substitute for the bamboo tablet and stylus4 ,subsequently he succeeded in making paper from bark1 tow1 old linen1 and fish nets 7,a4,d4 #aje74 ,he was created marquis in ,a4,d4 #aad for his long years of service and his ability4 ,a4,d4 #gjd4--;,it has been commonly asserted that raw cotton1 or cotton wool1 was first used by the ,arabs at this date for the manufacture of paper1 they having learnt the art from certain ,chinese prisoners captured at the occupation of ,samarkand by the ,arabs4 ,the complete conquest of ,samarkand does not1 however1 seem to have taken place until ,a4,d4 #gea1 and there is little doubt that this date should be accepted for the introduction of the art of paper-making among the ,arabs4 ,recent ,researches4--,professors ,wiesner and ,karabacek have ascertained one or two most important and interesting facts concerning the actual manufacture of pure rag paper4 ,in #ahgg a great quantity of ancient manuscripts was found at ,el-,faijum1 in ,egypt1 comprising about #ajj1jjj documents in ten languages1 extending from ,b4,c4 #adjj to ,a4,d4 #acjj1 many of which were written on paper4 ,the documents were closely examined in #ahid by these experts1 at the request of the owner1 the ,archduke ,rainer of ,austria4 ,researches of a later date resulted in the discovery of some further interesting documents which appear to establish with some degree of certainty the approximate date at which pure rag paper1 that is1 paper made entirely from rag1 was manufactured4 ,chinese documents dated ,a4,d4 #gfh-ghf1 which have been reported upon by ,dr4 ,hoernle1 and others dated ,a4,d4 #gha-ghb-ghg1 reported upon by ,dr4 ,stein as recently as #aija1 appear to show what materials were used by the ,chinese paper-makers in ,western ,turkestan4 ,the manuscripts mentioned were dug out from the sand-buried site of ,dandan ,uilig1 in ,eastern ,turkestan4 ,professor ,wiesner found that all the papers of the ,rainer collection were made of linen rag1 with an occasional trace of cotton1 probably added accidentally4 ,the earliest dated paper was a letter ,a4,d4 #hgd1 but two documents1 which from other reasons could be identified as belonging to ,a4,d4 #gib1 proved that at the end of the eighth century the ,arabs understood the art of making linen paper on network moulds1 and further that they added starch for the purpose of sizing and loading the paper4 ,professor ,karabacek advances some ingenious explanations as to the origin of the idea that raw cotton was first used for paper-making1 and he suggests that the legend owes its origin to a misunderstanding of terms4 ,in medival times paper was known as ,charta bombycina1 and sometimes as ,charta ,damascena1 the latter from its place of origin4 ,paper was also made in ,bambyce1 and a natural confusion arose between the terms1 since the word bombyx was used as a name for cotton1 and the paper commonly in use suggested that material to the mind of the observer1 and the name became corrupted to bombycina4 ,the suggestions of ,professor ,karabacek1 together with the microscopical investigations of ,dr4 ,wiesner1 appear to show that paper made entirely from raw cotton fibre was not known4 ,invention of ,rag ,paper4--,dr4 ,hoernle1 in discussing this question1 points out that1 taking ,a4,d4 #gea as the date when the ,arabs learnt the art of paper-making1 and ,a4,d4 #gib as the date when paper made entirely of linen rag was produced1 the date of the invention of rag paper must lie between these two dates4 ,the documents discovered in ,eastern ,turkestan and bearing the dates mentioned1 which papers fill up the gap between the years ,a4,d4 #gea and ,a4,d4 #gib1 were found to contain certain raw fibres1 such as ,china grass1 mulberry1 laurel1 as the main constituents1 and macerated flax and hemp rags as the minor constituents4 ,the addition and substitution of rag evidently increased in course of time1 and since the improvement thus effected soon became an obvious and established fact1 the raw fibres were omitted4 ,hence the credit of the manufacture of pure rag paper would be given to the people of ,samarkand1 the date being between the years ,a4,d4 #gfj and ,a4,d4 #gib2 and further the constitution of such paper has been shown by ,dr4 ,wiesner to be linen1 and not cotton1 as commonly stated4 ,these researches are of such interest that we quote ,professor ,hoernle's translation of the summary of the principal results of ,dr4 ,wiesner's examination of the ,eastern ,turkestani papers so recently discovered3-- ,taking into account the dates assigned to the papers on palographic grounds1 the following conclusions may be drawn from the examination of their material3-- 7#a7 ,the oldest of the ,eastern ,turkestani papers1 dating from the fourth and fifth centuries ,a4,d41 are made of a mixture of raw fibres of the bast of various dicotyledonous plants4 ,from these fibres the half-stuff for the paper was made by means of a rude mechanical process4 7#b7 ,similar papers1 made of a mixture of raw fibres1 are also found belonging to the fifth1 sixth1 and seventh centuries4 ,but in this period there also occur papers which are made of a mixture of rudely pounded rags and of raw fibres extracted by maceration4 7#c7 ,in the same period papers make their appearance in which special methods are used to render them capable of being written on1 viz41 coating with gypsum and sizing with starch or with a gelatine extracted from lichen4 7#d7 ,in the seventh and eighth centuries both kinds of papers are of equal frequency1 those made of the raw fibre of various dicotyledonous plants and those made of a mixture of rags and raw fibres4 ,in this period the method of extracting the raw fibre is found to improve from a rude stamping to maceration2 but that of preparing the rags remains a rude stamping1 and in the half-stuff thus produced from rags it is easy to distinguish the raw fibre from the crushed and broken fibre of the rags4 7#e7 ,the old ,eastern ,turkestani 7,chinese7 paper can be distinguished from the old ,arab paper1 not only by the raw fibres which accompany the rag fibres1 but also by the far-reaching destruction of the latter4 7#f7 ,the previous researches of ,professor ,karabacek and the author had shown that the invention of rag paper was not made in ,europe by ,germans or ,italians about the turn of the fourteenth century1 but that the ,arabs knew its preparation as early as the end of the eighth century4 ,the present researches now further show that the beginnings of the preparation of rag paper can be traced to the ,chinese in the fifth or fourth centuries1 or even earlier4 ,the ,chinese method of preparing rag paper never progressed beyond its initial low stage4 ,it was the ,arabs who1 having been initiated into the art by the ,chinese1 improved the method of preparing it1 and carried it to that stage of perfection in which it was received from them by the civilised peoples of ,europe in the medival ages4 7#g7 ,the author has shown that the process of sizing the paper with starch in order to improve it was already known to the ,arabs in the eighth century4 ,in the fourteenth century the knowledge of it was lost1 animal glue being substituted in the place of starch1 till finally in the nineteenth century1 along with the introduction of paper machines1 the old process was resuscitated4 ,but the invention of it was due to the ,chinese4 ,the oldest ,eastern ,turkestani paper which is sized with starch belongs to the eighth century4 7#h7 ,the ,chinese were not only the inventors of felted paper and the imitators of rag paper--though in the preparation of the latter they made use of rags only as a surrogate by the side of raw fibres--but they must also be credited with being the forerunners of the modern method of preparing 'cellulose paper4' ,for their very ancient practice of extracting the fibre from the bark and other parts of plants by means of maceration is in principle identical with the modern method of extracting 'cellulose' by means of certain chemical processes4 ,illustration3 ,,fig4 #b4--;,an ,early ,paper ,mill 7from ,kulturhistorisches ,bilderbuch1 ,a4,d4 #aefd74 ,paper-making in ,europe4--,the introduction of the art into ,europe seems to have taken place early in the eleventh century1 when the ,moors manufactured paper at ,toledo4 ,the early authorities who have studied this subject express the opinion that the paper produced in ,europe at this time was made from cotton rags and from raw cotton1 but1 in view of the recent researches into the composition of paper1 it is difficult to say how this idea arose1 unless we accept the explanation offered by ,professor ,karabacek4 ,in standard encyclopdias the following statements are made as to existing early documents printed on paper made in ,europe3-- ,a4,d4 #ajge4 ,syriac manuscripts of early date in the ,british ,museum4 ,a4,d4 #aajb4 ,a document printed on cotton1 being a deed of ,king ,roger of ,sicily1 now at ,vienna4 ,a4,d4 #aagh4 ,a treaty of peace between the ,kings of ,aragon and ,spain1 said to be printed on linen paper1 preserved at ,barcelona4 ,a4,d4 #abbc4 ,the ,liber ,plegierum1 printed on rough cotton paper4 ,one of the most interesting books on this subject is the ,historical ,account of the ,substances used to describe ,events from the ,earliest ,date1 by ,matthias ,koops1 published in #ahjj4 ,this writer appears to have obtained most of his information from ,german authorities4 ,the industry of paper-making passed through ,spain into ,italy1 ,france1 and the ,netherlands4 ,in #aahi paper was being manufactured at ,hainault1 in ,france1 and the industry rapidly spread all over the ,continent4 ,in #acij ,ulman ,stromer established a mill at ,nuremberg1 in ,germany1 employing a great number of men1 who were obliged to take an oath that they would not teach anyone the art of paper-making or make paper on their own account4 ,in the sixteenth century the ,dutch endeavoured to protect their industry by making the exportation of moulds for paper-making an offence punishable by death4 ,the bulk of the paper used in ,england was imported from ,france and ,holland1 and it was many years before the industry was established in ,england4 ,this is not surprising in view of the protective and conservative policy of the ,continental paper-makers4 ,illustration3 ,,fig4 #c4--,the ,paper ,mill of ,ulman ,stromer1 ,a4,d4 #acij 7supposed to be the oldest known drawing of a ,paper ,mill74 ,paper-making in ,england4--,the actual period at which the manufacture of paper was first started in ,england is somewhat uncertain4 ,the first mention of any paper-maker is found in ,wynkyn de ,worde's ,de ,proprietatibus ,rerum1 printed by ,caxton in #adie1 the reference being as follows3-- ,and ,john ,tate the younger1 joye mote he brok1 ,which late hathe in ,england1 doo ,make thys paper thynne1 ,that now in our ,englyssh ,thys booke is prynted inne4 ,john ,tate was the owner of a mill at ,stevenage1 ,hertfordshire4 ,in the household book of ,henry ,,vii4 an entry for the year #adii reads1 ,geven in rewarde to ,tate of the mylne1 #fs4 #h;d4 ,in #aehh a paper mill was erected by ,sir ,john ,spielman1 a ,german1 who obtained a licence from ,queen ,elizabeth for the sole gathering for ten years of all rags1 etc41 necessary for the making of paper4 ,this paper mill was eulogised by ,thomas ,churchyard in a long poem of forty-four stanzas1 of which we quote two3-- ,i prayse the man that first did paper make1 ,the only thing that sets all virtues forth2 ,it shoes new bookes1 and keeps old workes awake1 ,much more of price than all the world is worth3 ,it witnesse bears of friendship1 time1 and troth1 ,and is the tromp of vice and virtue both2 ,without whose help no hap nor wealth is won1 ,and by whose ayde great works and deedes are done4 ,six hundred men are set to worke by him ,that else might starve1 or seeke abroad their bread1 ,who now live well1 and goe full brave and trim1 ,and who may boast they are with paper fed4 ,strange is that foode1 yet stranger made the same1 ,for greater help1 ,i gesse1 he cannot give ,than by his help to make poore folk to live4 ,the industry made but little progress for some time after ,spielman's death1 and up till #afgj the supplies of paper were obtained almost entirely from ,france4 ,the first ,british patent for paper-making was granted to ,charles ,hildeyard in #affe for the way and art of making blue paper used by sugar bakers and others4 ,the trade received a great impetus on account of the presence of ,huguenots who had fled to ,england from ,france in consequence of the revocation of the edict of ,nantes in #afhe4 ,in #afie a company was formed in ,scotland for the manufacture of white and printing paper4 ,improvements in the art were slow until #agfj1 when ,whatman1 whose name has since become famous in connection with paper1 commenced operations at ,maidstone4 ,meantime the methods by which the rags were converted into paper were exceedingly slow and clumsy1 so that the output of finished paper was very small4 ,some interesting details as to the early manufacture of paper in ,england are given by ,mr4 ,rhys ,jenkins1 and from his account of ,early ,attempts at ,paper-making in ,england1 #adie-aghh1 the following extracts have been made3-- ,about #adif4 ,first attempts at paper-making by ,john ,tate at ,hertford4 #adif4 ,tate's paper used by ,wynkyn de ,worde in ,de ,proprietatibus ,rerum4 #aeeg4 ,a paper mill in existence at ,fenditton1 ,cambridge4 #aefi4 ,a mill at ,bemmarton1 ,wilts4 #aegd4 ,mill erected at ,osterley1 ,middlesex1 by ,sir ,thomas ,gresham4 #aehe4 ,richard ,tottyl asked for sole right to make paper for thirty-one years1 which was not granted4 #aehh4 ,john ,spilman erected a mill at ,dartford1 ,kent4 ,granted a patent for sole manufacture of paper4 #aehh4 ,churchyard's poem on the ,paper ,myll built near ,darthford by ,master ,spilman4 #afab4 ,robert ,heyricke's mill at ,cannock ,chase1 ,staffordshire4 #afcf4 ,the three or four paper mills in the neighbourhood of ,hounslow and ,colnbrook temporarily shut down on account of the plague1 the collection of rags having been forbidden4 #affe4 ,patent granted to ,charles ,hildeyard for an invention1 the way and art of making blew paper used by sugar bakers and others4 #afge4 ,approximate date of erection of mills at ,wolvercote1 ,oxford1 where the ,oxford ,india paper is now made4 #afgh4 ,mill at ,byfleet1 ,surrey1 mentioned by ,evelyn in his diary4 #afhb4 ,bladen--,a patent for an engine and process whereby rags are wrought into paper4 #afhd4 ,baysmaker--,a patent for the art and mistery of making paper in whole sheets4 #afhd4 ,jackson--,a patent for an engine1 either for wind or water1 which prepareth all materials whereof paper may be made4 ,evidently ,jackson was acquainted with the ,hollander beating engine4 #afhf4 ,a charter granted to the ,white ,paper ,makers' ,company for the sole right of making paper exceeding #ds4 a ream in value4 #afgd4 ,annual importation of paper1 presumably from ,france1 stated to be #afj1jjj reams1 of average value of #es4 7,somers74 #afhi4 ,trade with ,france prohibited by royal proclamation4 #afif4 ,price of paper very high owing to scarcity1 being #aas4 per ream4 #agab4 ,duties levied on all kinds of paper1 manufactured or imported4 #agbe4 ,monopoly of making paper for ,bank of ,england notes granted to ,de ,portal1 of the ,laverstoke mills1 ,hampshire4 ,this paper is still made by the firm of ,messrs4 ,portal4 #agci4 ,galliott and ,parry estimated that there were #fjj paper mills in ,england1 making #f1jjj reams a day4 ,the ,commissioner of ,excise reported only #bgh4 #agci4 ,james ,whatman erected a mill at ,boxley1 ,maidstone4 #ageh4 ,baskerville printed an edition of ,virgil on so-called woven paper4 ,early ,methods4--,the most rapid development of the industry appears to have taken place in ,holland4 ,the rags used for paper-making were moistened with water and stored up in heaps until they fermented and became hot4 ,by this means the dirt and non-fibrous matter was rendered partially soluble1 so that on washing a suitable paper pulp was obtained4 ,the washed rags were then placed in a stamping machine resembling an ordinary pestle and mortar4 ,the mortars were constructed of stone and wood1 and the stamps were kept in motion by levers which were raised by projections fixed on the shaft of a waterwheel4 ,the operation of beating thus occupied a long period1 but the paper produced was of great strength4 ,the invention of the ,hollander1 a simple yet ingenious engine which is deservedly known by the name of the country in which it first originated1 gave a tremendous impetus to the art of paper-making1 as by its means the quantity of material which could be treated in twenty-four hours was greatly increased4 ,unfortunately the date of the invention of this important machine has not been definitely traced4 ,the earliest mention of it seems to occur in ,sturm's ,vollstndige ,mhlen ,baukunst1 published in #agah4 ,it was in extensive use at ,saardam in #afig1 so that the invention is at least some years previous to #afij4 ,on this point ,koops says3 ,in ,gelderland are a great many mills1 but some so small that they are only able to make #djj reams of paper annually1 and there are also water mills with stampers1 like those in ,germany4 ,but in the province of ,holland there are windmills1 with cutting and grinding engines1 which do more in two hours than the others do in twelve4 ,in ,saardam #a1jjj persons are employed in paper-making4 ,,the ,,first ,,fourdrinier ,,paper ,,machine4 ,up till the year #agii paper was made entirely in sheets on a hand mould1 but during the last few years of the eighteenth century a ,frenchman1 ,nicholas ,louis ,robert1 manager for ,m4 ,didot1 who owned a paper mill at ,essones1 had been experimenting for the purpose of making paper in the form of a continuous sheet1 and eventually produced some of considerable length4 ,the idea was taken to ,england by ,didot's brother-in-law1 ,gamble1 and introduced to the notice of ,messrs4 ,fourdrinier1 wholesale stationers1 of ,london4 ,illustration3 ,,fig4 #d4--,the ,first ,paper ,machine1 ,a4,d4 #ahjb4 ,plan and ,elevation4 ,the first machine was naturally a very crude affair4 ,it consisted of an endless wire cloth stretched in a horizontal position on two rollers1 one of which rotated freely in a bearing attached to the frame of the machine1 the other being fitted in an adjustable bearing so that the wire could be tightened up when necessary4 ,the beaten pulp1 contained in a vat placed below the wire1 was thrown up in a continual stream upon the surface of the wire1 and carried forward towards the squeezing rolls4 ,a shaking motion was imparted to the travelling wire so as to cause the fibres to felt properly4 ,a great deal of the water fell through the meshes of the gauze1 and further quantities were removed by means of the press rolls4 ,the wet paper was then wound up on to a wooden roller1 which was taken out as soon as sufficient paper had been made4 ,illustration3 ,,fig4 #e4--,the ,improved ,paper ,machine of ,a4,d4 #ahaj4 ,the whole process was carried on under great difficulties1 but substantial improvements were soon made by the enterprising ,fourdriniers1 who commenced operations in ,bermondsey1 employing ,mr4 ,bryan ,donkin1 then in the service of ,messrs4 ,hall ,co41 of ,dartford1 who had shown himself keenly interested in the machine4 ,in #ahjc the first ,fourdrinier1 so called1 was built at ,bermondsey1 and erected at ,two ,waters ,mill in ,herefordshire4 ,in this machine the mixture of pulp and water was carried forward between two wires1 and1 after passing through the couch rolls1 transferred to an endless felt4 ,this arrangement proved to be faulty because the water did not escape freely enough from the wire1 and a great deal of the paper was spoilt4 ,donkin1 however1 hit upon a simple but effective device for curing this fault by altering the relative position of the two couch rolls4 ,instead of keeping the two rolls exactly in a vertical position one over the other1 he placed them at a slight angle so that the upper one should bear gently on the web of paper carried by the wire before receiving the full pressure of the rolls1 and thus remove a greater proportion of the water4 ,in this way the paper was firmer and less liable to break when pressed between the couch rolls1 an additional advantage being secured in the fact that the upper wire could be dispensed with4 ,the various improvements effected resulted in a machine the details of which appear in the appended diagram1 the device of the inclined couch rolls being fitted about #ahaj4 ,the mixture of water and pulp flowed from a stuff chest into a small regulating box and on to the wire over a sloping board4 ,the pulp at once formed into a wet sheet of paper1 the water falling through the meshes of the wire1 being caught in a bucket-shaped appliance1 and conveyed back to the regulating box4 ,the stream of pulp was confined upon the wire by means of a deckle4 ,further quantities of water were removed by the aid of a pair of squeezing rolls before the web passed through the couch rolls after which the paper was reeled up on a wooden spindle4 ,from this date the success of the machine was assured1 though the inventor and his colleagues were practically ruined1 an experience only too common with the early pioneers of many great and useful industrial enterprises4 ,in fact1 the firm of ,messrs4 ,donkin were the only people to profit from the invention1 for they manufactured a number of machines1 as stated in the report of the ,jurors of the ,exhibition of #ahea1 and from #ahjc to #ahea no less than #aij ,fourdriniers were set to work4 ,,chapter ,,ii ,,cellulose ,,and ,,paper-,,making ,,fibres ,when plants such as flax1 cotton1 straw1 hemp1 and other varieties of the vegetable kingdom are digested with a solution of caustic soda1 washed1 and then bleached by means of chloride of lime1 a fibrous mass is obtained more or less white in colour4 ,this is the substance known to paper-makers as paper pulp1 and the several modifications of it derived from different plants are generally known to chemists as cellulose4 ,although plants differ greatly in physical structure and general appearance1 yet they all contain tissue which under suitable treatment yields a definite proportion of this fibrous substance4 ,the preparation of a small quantity of cellulose from materials like straw1 rope1 hemp1 the stringy bark of garden shrubs1 wood1 and bamboo can easily be accomplished without special appliances4 ,soft materials1 such as straw and hemp1 are cut up into short pieces1 hard substances like wood and bamboo are thoroughly hammered out1 in order to secure a fine subdivision of the mass4 ,the fibre so prepared is then placed in a small iron saucepan1 and covered with a solution made up of ten parts of caustic soda and #ajj parts of water4 ,the material is boiled gently for eight or ten hours1 the water which is lost through evaporation of steam being replaced by fresh quantities of hot water at regular intervals4 ,when the fibrous mass breaks up readily between the fingers1 it is poured into a sieve1 or on a piece of muslin stretched over a basin1 and washed completely with hot water until clean and free from alkali4 ,hard pieces and portions which seem incompletely boiled are removed1 and the residual fibres separated out4 ,these fibres are placed in a weak1 clear solution of ordinary bleaching powder1 left for several hours1 and subsequently thoroughly washed4 ,this simple process will give a more or less white fibrous material4 ,the purest form of cellulose is cotton4 ,a very slight alkaline treatment1 followed by bleaching1 is sufficient to remove the non-fibrous constituents of the plant1 and a large yield of cellulose is obtained4 ,for this reason the cotton fibre ranks high as an almost ideal material for paper-making1 possessing the quality of durability4 ,cellulose is an organic compound1 containing carbon1 hydrogen1 and oxygen in the following proportions3-- ,carbon #ddb ,hydrogen #fc ,oxygen #die ----- #ajjj ,its composition is represented by the formula ,c#f;,h#aj,o#e4 ,the celluloses obtained from various plants are not identical either in physical structure and chemical constitution1 or as to their behaviour when employed for paper-making4 ,in fact1 the well-known differences between the raw materials used for paper-making1 and also between the numerous varieties of finished paper1 are to be largely accounted for and explained by a careful study of the cellulose group1 particularly with reference to the microscopic characteristics and the chemical composition of the individual species4 ,the only vegetable substance which may be regarded as a simple cellulose is cotton1 all others being compound celluloses of varying constitution1 the nature of which cannot be appreciated without a considerable knowledge of chemistry4 ,the classification of such plants1 therefore1 in a book of this description must be limited to certain distinctions having some immediate practical bearing on the question of paper manufacture4 ,cotton4--,regarded as the typical simple cellulose1 containing #ia per cent4 of cellulose1 and remarkable for its resistance to the action of caustic soda4 ,linen4--,the cellulose isolated from flax by treatment with alkali or caustic soda cannot readily be distinguished from cotton cellulose by chemical analysis or reactions4 ,the difference is almost entirely a physical one4 ,flax is a typical compound cellulose1 to which has been given the name pecto-cellulose on account of certain properties4 ,other well-known plants of this class are ramie1 aloe1 sunn hemp1 manila4 ,esparto4--,the cellulose isolated from esparto differs in composition from cotton cellulose3-- ,carbon #daj ,hydrogen #eh ,oxygen #ecb ----- #ajjj ----- ,it is regarded as an oxycellulose1 being readily oxidised by exposure to air at #ajj ,c4 ,other oxycelluloses familiar to the paper-maker are straw1 sugarcane1 bamboo4 ,wood4--,the difference between wood and the plants already mentioned is expressed by the term lignified fibre or ligno-cellulose4 ,this term is used to indicate that the wood is a compound cellulose containing non-fibrous constituents1 to which has been given the name lignone4 ,jute is another example of this class4 99 99 99 99 99 ,these distinctions may be exemplified by reference to a simple experiment4 ,if three papers1 such as a pure rag tissue or a linen writing1 an ordinary esparto printing1 and a cheap newspaper containing about #hj per cent4 of mechanical wood1 are heated for twenty-four hours in an oven at a temperature of #aje ,c41 the first will undergo little1 if any1 change in colour1 while the others will be appreciably discoloured1 the mechanical wood pulp paper most of all4 ,this change is due to the gradual oxidation of the constituents of the paper1 the ligno-cellulose of the mechanical wood pulp being most readily affected by the high temperature1 and the pure cellulose of the rag paper being least altered4 ,the process of oxidation1 brought about rapidly under the conditions of the experiment described1 takes place in papers of low quality exposed to air in the ordinary circumstances of daily use1 but of course at an extremely slow rate4 ,the deterioration of such paper is not1 however1 due to the simple oxidation of the cellulose compounds1 because other factors have to be taken into account4 ,the presence of impurities in the paper on the one hand1 and of chemical vapours in the air on the other1 hastens the decay of papers very considerably4 ,percentage of ,cellulose in ,fibrous ,plants4--,the value of a vegetable plant for paper-making is first determined by a close examination of the physical structure of the cellulose isolated by the ordinary methods of treatment4 ,if the fibres are weak and short1 the raw material is of little value1 and it is at once condemned without further investigation1 but should the fibre prove suitable1 then the question of the percentage of cellulose becomes important4 ,there are several methods employed for estimating the amount of cellulose in plants4 ,the process giving a maximum yield is known as the chlorination method1 the details of which are as follows3--,about ten grammes of the air-dried fibre is dried at #ajj ,c4 in a water oven for the determination of moisture4 ,a second ten grammes of the air-dried fibre is boiled for thirty minutes with a weak solution of pure caustic soda 7ten grammes of caustic soda in #a1jjj cubic centimetres of water71 small quantities of distilled water being added at frequent intervals to replace water lost by evaporation4 ,the residue is then poured on to a piece of small wire gauze1 washed thoroughly1 and squeezed out4 ,the moist mass of fibre is loosened and teased out1 placed in a beaker1 and submitted to the action of chlorine gas for an hour4 ,the bright yellow mass is then washed with water and immersed in a solution of sodium sulphite 7twenty grammes of sodium sulphite in #a1jjj cc4 of water74 ,the mixture is slowly heated1 and finally boiled for eight to ten minutes1 with the addition of #aj cc4 of caustic soda solution4 ,the residue is washed1 immersed in dilute sodium hypochlorite solution for ten minutes1 again washed1 first with water containing a little sulphurous acid and then with pure distilled water4 ,it is finally dried and weighed4 ,the second process for estimating cellulose is based upon the use of bromine and ammonia4 ,about ten grammes of the air-dried fibre is placed in a well-stoppered wide-mouthed bottle with sufficient bromine water to cover it4 ,as the reaction proceeds the red solution gradually decolourises1 and further small additions of bromine are necessary4 ,the mass is then washed1 and boiled in a flask connected to a condenser with a strong solution of ammonia for about three to four hours4 ,the fibrous residue is washed1 again treated with bromine water in the cold1 and subsequently boiled with ammonia4 ,the alternative treatment with bromine and ammonia is repeated until a white fibrous mass is obtained4 ,in practice the paper-maker is confined to two or three methods for the isolation of the fibres1 viz41 alkaline processes1 which require the digestion of the material with caustic soda1 lime1 lime and carbonate of soda1 chiefly applied to the boiling of rags1 esparto1 and similar pecto-celluloses2 acid processes1 in which the material is digested with sulphurous acid and sulphites4 ,the latter methods are at present almost exclusively used for the preparation of chemical wood pulp4 ,yields of ,cellulose in the ,paper ,mill4--,the object of the paper-maker is to obtain a maximum yield of cellulose residue at a minimum of cost4 ,usually the amount of actual bleached paper pulp obtained in the mill is less than the percentage obtained by careful quantitative analysis1 for reasons easily understood4 ,in the first place1 the raw material is digested for a stated period with a carefully measured quantity of caustic soda1 for example1 at a certain temperature4 ,now the conditions of boiling may be varied by altering one or more of these factors1 the period of boiling1 the strength of solution1 or the steam pressure1 and the paper-maker must exercise his judgment in fixing the exact relation between the varying factors so as to produce the best results4 ,in the second place1 the mechanical devices for washing the boiled pulp and for bleaching cause slight losses of fibre1 which cannot be altogether avoided when operations are conducted on a large scale4 ,frequently1 also1 a greater yield of boiled material may involve a larger quantity of bleaching powder1 so that it is evident the adjustment of practical conditions requires considerable technical skill and experience4 ,the percentage of cellulose in the vegetable plants employed more or less in the manufacture of paper is given in the following table3-- ,,table ,,showing ,,percentage ,,of ,,cellulose ,,in ,,fibrous ,,plants4 ---------------------------------------- --- ,fibre4 ,cellulose1 per cent4 ---------------------------------------- --- ,cotton #iaj ,flax #hbj ,hemp #ggj ,ramie #gfj ,manila #fdj ,jute #fdj ,wood 7pine7 #egj ,bagasse #ejj ,bamboo #dhj ,esparto #dh to #db ,straw #dh to #dj ---------------------------------------- --- ,the ,properties of ,cellulose4--,cellulose is remarkably inert towards all ordinary solvents such as water1 alcohol1 turpentine1 benzene1 and similar reagents1 a property which renders it extremely useful in many industries1 with the result that the industrial applications of cellulose are numerous and exceedingly varied4 ,solubility4--,cellulose is dissolved when brought into contact with certain metallic salts1 but it behaves quite differently to ordinary organic compounds4 ,sugar1 for example1 is a crystalline body soluble in water1 and can be recovered in a crystalline state by gradual evaporation of the water4 ,cellulose under suitable conditions can be dissolved1 but it cannot be reproduced in structural form identical with the original substance4 ,if cellulose is gently heated in a strong aqueous solution of zinc chloride1 it gradually dissolves1 a thick syrupy mass being obtained1 which consists of a gelatinous solution of cellulose4 ,if the mixture is diluted with cold water1 a precipitate is produced consisting of cellulose hydrate intimately associated with oxide of zinc1 which latter can be dissolved out by means of hydrochloric acid4 ,the resulting product is not1 however1 the original substance1 but a hydrated cellulose1 devoid of any crystalline structure4 ,cellulose is also soluble in ammoniacal solutions of cupric oxide1 from which it can be precipitated by acids or by substances which act as dehydrating agents1 e4g41 alcohol4 ,hydrolysis4--,an explanation of the behaviour of cellulose towards the solvents already mentioned1 and towards acid and alkali1 requires a reference to its chemical composition4 ,the substance is a compound of carbon1 hydrogen1 and oxygen represented by the formula ,c#f;,h#aj,o#e being one of a class of organic compounds known as carbohydrates1 so designated because the hydrogen and oxygen are present in the proportions which exist in water4 ,water ,hydrogen ,oxygen ,h#b ,o4 ,the ,h#aj,o#e in the cellulose formula corresponds to #e 7,h#b,o74 ,when cellulose is acted upon by acid1 alkali1 and certain metallic salts1 it enters into combination with one or more proportions of water1 forming cellulose hydrates of varying complexity4 ,this change is usually termed hydrolysis4 ,with mineral acids like sulphuric and hydrochloric acids1 cellulose1 if boiled in weak solutions1 is converted into a non-fibrous brittle substance having the composition ,c#ab;,h#bj,o#aj #b ,h#b,o to which the name hydra-cellulose has been given4 ,similar changes occur1 but at a much slower rate1 when cellulose is in contact with free acids at ordinary temperatures4 ,for this reason it is important that paper1 when finished1 should not be contaminated with free acid4 ,the nature and extent of the chemical change can be varied by altering the strength of the acid and the conditions of treatment4 ,the manufacture of parchment paper is an example of the practical utility of the chemical reaction between cellulose and acid4 ,a sheet of paper is dipped into a mixture of three parts of strong sulphuric acid and one part of water1 when it becomes transparent4 ,left in the solution it dissolves1 but if taken out and dipped into water in order to wash off the acid the reaction is stopped1 and a tough semi-transparent piece of parchment is obtained4 ,the cellulose is more or less hydrated1 having the composition ,c#ab;,h#bj,o#aj ,h#b,o1 a substance having the name amyloid4 ,oxidation4--,cellulose is only oxidised to any appreciable extent by acid and alkali if treated under severe conditions4 ,it is remarkable that the processes necessary for isolating paper pulp from plants when digested with these chemical reagents do not act upon or destroy the fibre1 and this capacity for resisting oxidation has rendered cellulose extremely valuable to many of the most important industries4 ,the resistant power of the cellulose is1 however1 broken down by the use of acid and alkali in concentrated form4 ,oxalic and acetic acids are obtained when cellulose is heated strongly at #bej ,c4 with solid caustic soda4 ,oxy-cellulose1 a white friable powder1 is produced by means of strong mineral acids4 ,nitric acid at #ajj ,c4 attacks the fibre very readily and produces about #cj-dj per cent4 of the oxidised cellulose4 ,,cellulose ,,derivatives4 ,the great number of compounds and derivatives1 i4e41 substances obtained by chemical treatment1 may be judged from the following list4 ,the substances of commercial importance are suitably distinguished from those of merely scientific interest by the printing of the names in small capitals4 ,,acetic ,,acid4--,an important commercial product obtained by the destructive distillation of wood4 ,the crude pyroligneous acid is first neutralised with chalk or lime1 and the calcium acetate formed then distilled with sulphuric acid4 ,wood yields #e to #aj per cent4 of its weight of acetic acid according to the nature of the wood4 ,,acetone4--,a solvent for resins1 gums1 camphor1 gun cotton1 and other cellulose products4 ,prepared by distilling barium or calcium acetate in iron stills1 the acetate being obtained from the crude acetic acid produced by the dry distillation of wood4 ,acid ,cellulose4--7,see ,hydral-,cellulose47 ,adipo-,cellulose4--,a distinct compound cellulose present in the complex cuticular tissue of plants1 and separated easily by suitable solvents from the wax and oily constituents also present4 ,,alkali ,,cellulose4--,when cotton pulp is intimately mixed with strong caustic soda solution1 this compound is formed4 ,it is utilised in the manufacture of ,viscose4 ,amyloid4--,strong sulphuric acid acts upon cellulose and converts it into a gelatinous semi-transparent substance to which the name amyloid has been given4 7,see ,parchment ,paper47 ,,ballistite4--,a smokeless powder composed of nearly equal parts of nitro-glycerine and nitrated cellulose1 with a small quantity of diphenylamine4 ,carbohydrate4--,a large number of important commercial products1 such as cellulose1 sugars1 starches1 and gums1 consist of the elements carbon1 hydrogen1 and oxygen1 associated in varying proportions4 ,the ratio of hydrogen to oxygen in these compounds is always #b3a 7,h#b and ,o74 ,cellulose ,c#f;,h#aj,o#e4 ,sugar ,c#f;,h#ab,o#f4 ,dextrin n 7,c#f;,h#aj,o#e74 ,to all these substances the term carbohydrate is applied4 ,celloxin 7,tollens74--,a substance having the stated composition ,c#h;,h#f,o#f considered to be present in oxidised derivatives of cellulose4 ,,celluloid4--,this well-known material is made by incorporating camphor with nitro-cellulose1 a plastic ivory-like substance being produced4 ,in practice the process is as follows3--,wood pulp or wood pulp paper is saturated with a mixture of sulphuric acid 7five parts7 and nitric acid 7two parts71 which produces nitrated cellulose4 ,the product is washed1 ground1 and mixed with camphor1 the mastication being effected by heavy iron rollers4 ,the mass thickens and can be removed in the form of thick sheets4 ,these sheets are submitted to great pressure between steam-heated plates4 ,the cake obtained is cut into sheets of any desired thickness1 seasoned by prolonged storage1 and afterwards worked up into boxes1 combs1 brush-backs1 and many other domestic articles of a useful and ornamental character4 ,,cellulose ,,acetate 7,cross74--,if cellulose is heated with acetic anhydride at #ahj ,c41 viscous solutions of the acetates are obtained4 ,the process yielding a definite acetate of commercial value is based upon the following reaction3--#ajj parts of cellulose prepared from the sulpho-carbonate are mixed with #abj parts of zinc acetate1 heated and dried at #aje ,c4 ,acetic anhydride is added in small quantity1 and #ajj parts of acetyl chloride4 ,at a temperature of #ej ,c4 the mixture becomes liquid1 and cellulose acetate is subsequently obtained as a white powder4 ,the compound can be used in the place of cellulose nitrate1 and1 being non-explosive1 may gradually replace the latter in many industrial applications4 ,cellulose-,benzoate4--,when alkali cellulose is heated with benzoyl chloride and excess of caustic soda1 this substance is obtained4 ,cellulose ,hydrate4--,the substances produced by the action of acid and alkali on cellulose under certain strictly defined conditions are bodies containing cellulose united with water to form hydrates4 ,the industrial applications of cellulose based upon this reaction are described under the special headings4 ,,cellulose ,,nitrate4--,a considerable number of derivatives are obtained by bringing cellulose into contact with nitric acid4 ,variations in the strength of the acid1 the temperature of reaction1 and the time of contact determine the nature of the product4 ,the best known nitrates are3-- ,cellulose di-nitrate4 ,cellulose tri-nitrate and tetra-nitrate1 present chiefly in pyroxyline4 ,cellulose penta-nitrate4 ,cellulose hexa-nitrate1 the chief constituent of gun-cotton4 ,,charcoal4--,not a cellulose derivative in the strict sense of the term1 charcoal being a residue obtained in the dry distillation of wood4 ,,collodion4--,a soluble nitrate of cellulose used in photography4 7,see ,pyroxyline47 ,,cordite4--,a smokeless powder consisting mainly of nitro-glycerine and gun-cotton mixed with acetone4 ,the materials are thoroughly incorporated and the resultant paste formed into threads which are dyed and then cut up into suitable lengths for cartridges4 ,cuto-,cellulose4--,synonymous with adipo-cellulose4 ,dextron4--,a compound prepared from the waste liquors of the bisulphite process used for the manufacture of wood pulp4 ,resembles dextrin in its physical properties4 ,,dextrose4--,a carbohydrate which can be obtained by the action of mineral acids on cellulose4 ,commercial dextrose1 or glucose1 is prepared by the conversion of starch with sulphuric acid4 ,the starch is mixed with dilute acid at a fixed temperature1 and the starch milk obtained poured gradually into a vessel containing dilute acid1 which is maintained at boiling point4 ,the conversion is complete and rapid4 ,,explosives4--,the production of the several cellulose nitrates has given rise to a great number of highly explosive substances4 ,blasting ,gelatine4--,a mixture of nitro-glycerine with cellulose nitrates4 ,amberite1 ,ballistite1 ,cordite1 and other smokeless powders1 consisting of nitro-glycerine and cellulose nitrates in about equal proportions4 ,sporting powders made by mixing nitro-cellulose with barium nitrate1 camphor nitro-benzene1 such as indurite1 plastomenite1 etc4 ,,glucose4--7,see ,dextrose47 ,,gun-,,cotton4--,an explosive prepared by the action of nitric acid on cotton4 ,selected cotton waste suitably opened up is immersed in a mixture of three parts of nitric acid by weight 7#aej sp4 gr47 and one part of sulphuric acid by weight 7#ahe sp4 gr47 and submitted to a number of processes by which the nitration is properly effected so as to produce a nitro-cellulose of uniform composition4 ,the material is washed1 reduced to pulp1 and moulded into various forms4 ,hemi-,cellulose4--,the constituents of plant tissues are extremely varied in character4 ,many plants contain substances which resemble true cellulose1 but differing from it in being easily converted by hydrolysis1 and by the action of dilute acids1 into carbohydrates4 ,plants which contain a large proportion of such constituents are termed hemi-celluloses4 ,in some cases certain crystallisable sugars can be obtained by hydrolysis under suitable conditions4 ,hydral-,cellulose 7,bumcke74--,a compound of merely scientific interest1 resulting from the treatment of cellulose with hydrogen peroxide4 ,when acted upon by alkali it is decomposed into cellulose and acid cellulose1 the latter a derivative of unstable composition4 ,hydro-,cellulose4--,this product1 a white1 non-structureless1 friable powder1 is obtained by treating cellulose with hydrochloric or sulphuric acid of moderate strength4 ,the substance itself has no commercial value1 but the reaction is useful in separating cotton from animal fabrics4 ,if a woollen cloth containing cotton is soaked in dilute sulphuric acid1 washed1 and dried at a gentle heat1 the cotton is acted upon1 and can be beaten out of the fabric1 the wool resisting the acid treatment4 ,lignin4--,the complex mixture of substances which is associated with cellulose in wood1 jute1 and other ligno-celluloses4 ,the conversion of wood into chemical pulp effects the removal of this material more or less completely4 ,the well-known phloroglucine test for mechanical wood in papers is based upon the presence of lignin in the wood4 ,ligno-,cellulose4--,wood and jute are typical bodies consisting of cellulose and complex non-cellulose1 generally described as lignin1 associated together in the plant tissue4 ,the chemistry of the non-cellulose portion of wood is a matter still under investigation1 its importance from a commercial point of view being obvious from the fact that the removal of the lignin during the conversion of the wood into wood-cellulose results in a loss of #ej per cent4 of the weight of wood4 ,lustra-,cellulose4--,synonymous with and suggested as a more appropriate name for the material usually described as artificial silk4 ,,mercerised ,,cotton4--,when cotton is immersed in strong solutions of caustic soda a remarkable change sets in4 ,the physical structure of the fibre is entirely altered from the long flattened tube having a large central canal to a shorter cylindrical tube in which the canal almost disappears4 ,hydration of the cellulose takes place1 and these changes are taken advantage of in the production of mercerised cloth 7so named from the discoverer of the reaction1 ,mercer74 ,cotton goods1 particularly those made of long stapled cotton1 when mercerised1 exhibit a beautiful lustre1 and some magnificent crpon effects are obtained by the process4 ,methoxyl4--,a constituent of the complex compound known as ligno-cellulose1 which is present in wood and similar fibres4 ,the amount of methoxyl in lignified tissue can be accurately determined1 and it has been suggested that the proportion of methoxyl found in a cheap printing paper could be used as a measure of mechanical wood pulp present4 ,muco-,cellulose4--,this term is applied to certain compound celluloses present chiefly in mucilages1 gums1 and in seaweeds 7,alg74 ,the natural substances are all of commercial importance--,iceland moss1 ,carragheen1 ,algin1 etc4 ,,naphtha4--,one of the products of the dry distillation of wood1 usually described as wood-naphtha1 or wood spirit4 ,,nitro-,,cellulose4--,the treatment of cellulose with nitric acid gives a number of nitro-celluloses according to the conditions of the process4 7,see ,cellulose ,nitrates47 ,,oxalic ,,acid4--,a substance of great commercial importance prepared by heating the sawdust of soft wood1 such as pine1 fir1 and poplar1 with strong solutions of mixed caustic soda and potash to dryness4 ,the wood yields after six hours a greyish mass containing about #bj per cent4 of the acid1 which is separated out by water and then crystallised4 ,it is used for bleaching1 and as a discharge in calico printing and dyeing4 ,oxy-,cellulose4--,a white friable powder produced by treating cellulose with nitric acid at #ajj ,c4 ,the oxidation of cellulose is brought about by several reagents such as chromic acid1 hypochlorites of lime and soda1 chlorine1 and permanganates4 ,the extent to which cloth has been damaged by overbleaching may be determined by a simple test with methylene blue solution1 which is readily absorbed by oxy-cellulose present in such fabrics4 ,,parchment4--,a tough paper prepared by the action of sulphuric acid on unsized paper4 7,see page #acg47 ,pectins4--7,see ,pecto-,cellulose47 ,pecto-,cellulose4--,a generic term applied to many important fibrous materials1 such as flax1 straw1 esparto1 bamboo1 phormium1 ramie1 c41 which on alkaline treatment yield cellulose for paper-making1 and a non-fibrous soluble residue of complex composition4 ,these soluble derivatives are known as pectin 7,c#cb;,h#dh,o#cb71 pectic acid 7,c#cb;,h#dd,o#cj71 and metapectic acid 7,c#cb;,h#bh,o#cf74 ,although the soluble constituents of the pecto-celluloses amount to #ej per cent4 by weight in most cases1 no process for the recovery of the product in a commercial form has yet been devised4 7,see description of ,soda recovery1 page #gh47 ,,pyroxyline4--,a substance prepared by nitrating cotton4 ,the cotton is immersed in a mixture of nitric and sulphuric acids of carefully regulated strength1 and subsequently washed free of the acid4 ,three volumes of nitric acid 7sp4 gr4 #adbi7 are diluted with two volumes of water and nine volumes of strong sulphuric acid 7sp4 gr4 #ahci7 added4 ,to the solution when cool the cotton is added in small quantities at a time4 ,the resultant pyroxyline is soluble in a mixture of equal quantities of alcohol and ether1 and in the soluble form is utilised as collodion for photography4 ,,silk1 ,,artificial4--,a remarkable substance made from wood or cotton cellulose1 closely resembling silk in appearance and physical properties4 ,nitrated cellulose is dissolved in a mixture of equal parts of alcohol and ether4 ,the solution is forced through five capillary tubes under high pressure1 and the filament so obtained solidifying at once is wound together with other similar filaments upon suitable bobbins4 ,various modifications of this general process are in use1 such as the solidification of the solution into threads by passing it into water2 the application of solvents less inflammable than ether and alcohol2 the use of other forms of dissolved cellulose such as those prepared by means of zinc chloride1 ammoniacal copper oxide1 or acetic anhydride4 ,in all cases the yarn or thread is submitted to further chemical treatment for the removal of nitric acid and to render the material non-explosive and less inflammable4 ,the finished product is soft and supple1 can be easily bleached and dyed1 and is capable of acquiring a high lustre4 ,,smokeless ,,powders4--7,see ,explosives47 ,sulpho-,carbonate4--7,see ,viscose47 ,,sulphate ,,cellulose4--,chemical wood pulp prepared by the sulphate process4 7,see page #ajg47 ,,sulphite ,,cellulose4--,chemical wood pulp prepared by the sulphite process4 7,see page #ajg47 ,,viscose4--,a soluble sulpho-carbonate of cellulose1 prepared by treating cellulose with a #ae per cent4 solution of caustic soda1 and shaking the product with carbon bisulphide in a closed vessel4 ,the mixture forms a yellowish mass soluble in water1 giving a viscous solution which has some remarkable and valuable properties4 ,this viscose1 on standing1 coagulates to a hard mass which can be turned and polished4 ,if spread on glass and coagulated by heat1 films are obtained from which the alkaline by-products can be washed out4 ,these films are transparent1 colourless1 very tough and hard4 ,,vulcanised ,,fibre4--,fibre or pulp treated with zinc chloride in acid solution1 or otherwise1 for the manufacture of hard boards4 7,see page #aci47 ,,willesden ,,goods4--,paper1 fibre1 and textiles when treated with cuprammonium oxide are partially gelatinised on the surface and rendered waterproof4 7,see page #aci47 ,wood ,spirit4--7,see ,naphtha47 ,xylonite4--7,see ,celluloid47 ,,fibres ,,for ,,paper-,,making4 ,although the vegetable world has been explored from time to time for new supplies of cellulose1 and some plants have been found serviceable in certain directions1 yet the number of fibres in actual use is very limited4 ,the following table indicates the principal sources of the material required for paper-making3-- ---------------------------------------- ---------------------------- ,fibre4 ,source of the ,fibre4 ,application of the ,fibre4 ---------------------------------------- ---------------------------- ,linen ,rags1 textile waste4 ,high class writings and printings4 ,cotton ,rags1 textile waste4 ,high class writings and printings4 ,esparto ,natural grass4 ,writings and printings4 ,straw ,straw from various ,printings1 box and card boards4 cereals--wheat1 barley1 oats1 etc4 ,wood ,mechanically ground wood4 ,cheap papers1 boxboards1 middles1 tickets and cards1 writings and printings4 ,chemically prepared wood4 ,writings and printings4 ,flax ,threads1 waste from ,wrappings1 boards1 cable spinning mills4 papers4 ,hemp ,spinning refuse1 old rope1 ,wrappings1 boards1 cable sailcloth1 etc4 papers1 strong writings4 ,jute ,waste1 old gunny bags4 ,wrappings1 boxboard1 cards4 ,bamboo ,natural stems4 ,writings and printings 7not in ,europe1 and only limited quantities elsewhere74 ,ramie ,bast fibres of the plant2 ,rarely used1 except in special textile refuse4 cases4 ,bagasse ,sugar-cane refuse4 ,common papers 7chiefly experimental results74 ,manila ,textile and rope refuse4 ,wrappings1 cable papers4 ,hemp ---------------------------------------- ---------------------------- ,exploiting ,new ,fibres4--,the exploitation of any new paper-making fibre requires attention to certain important details1 which may be fairly considered in the following order3-- 7#a7 ,supply4--,the supply of material must be plentiful and obtainable in large quantities4 ,too often this question is entirely neglected by those who bring new fibres to the notice of paper-makers1 probably because they do not realise that enormous quantities of material are necessary to supply even a very small section of the paper trade1 the fact being that few plants yield more than half their weight of paper-making fibre4 7#b7 ,suitability4--,the fibre should be properly examined as to its chemical and physical properties in a laboratory equipped with appliances for its conversion into bleached paper pulp on a small scale4 ,the examination of the fibre would include tests as to the amount of pulp which can be obtained from one ton of raw material1 the approximate cost of treatment1 and details as to the value of the fibre for paper-making4 7#c7 ,cost of ,raw ,material4--,if the supply of material seems to be sufficient1 and the paper pulp obtained possesses suitable qualities1 then it is necessary to get accurate information as to the cost of the fibre delivered to some given spot at or near the place of collection4 ,the exploitation of any new fibre for paper-making purposes will involve a recognition of the fact that the raw material must be converted into pulp at or near the place where the material is most abundant4 ,the only interesting exception to this is the case of esparto fibre1 which is imported into ,england in large amount1 but this is only possible because esparto possesses most valuable paper-making qualities1 and is obtained in countries close to ,england1 where large quantities are consumed4 ,it is doubtful whether other fibres could be utilised in the same way4 7#d7 ,the ,cost of ,manufacture at or near the place of collection requires to be carefully worked out1 due consideration being given to the actual cost of chemicals on the spot1 cost of labour1 and the conditions under which the maintenance of machinery can be efficiently looked after4 7#e7 ,carriage and ,freight ,charges are the last1 but by no means the least1 items of importance4 ,it is not too much to say that the whole success of the exploitation of new paper-making fibre hangs entirely upon this item1 the majority of many fibres which have been brought to the notice of the trade being suitable1 but impracticable1 solely on account of these and similar commercial considerations4 ,in the pages of the trade press for the last few years the following fibres have been noticed3-- 7#a7 ,flax ,pulp4--,this material was to be obtained from flax straw4 ,attempts were made on a commercial scale to produce quantities of flax fibre1 but so far the efforts made have not been very successful4 7#b7 ,ramie ,fibre4--,this material has been exploited over and over again1 chiefly for textile trades1 its application as a paper-making material being limited to small quantities used for special purposes such as bank notes4 ,the fibre is too valuable1 except for textile industries1 and can only come into the paper trade as a waste material from such sources4 7#c7 ,tobacco ,fibre has been before the trade for some years1 the idea being to utilise tobacco stems and other tobacco waste for the manufacture of paper suitable for use as wrappers for cigars1 cigarettes1 and similar purposes4 7#d7 ,agave ,fibre4--,this name is given to a large and important genus of fibre-yielding plants found chiefly in ,central ,america4 ,it is also found in ,india1 and in #ahgh an experiment was made for the manufacture of paper at a mill near ,bombay1 but this did not give any satisfactory results1 probably on account of the primitive methods used in treatment4 7#e7 ,bagasse4--,the waste material from sugar-cane has been looked upon for many years as a desirable fibre1 much time and labour having been given to the utilisation of this material4 ,in spite of these efforts bagasse still remains an almost useless and unworkable material4 ,this is partly due to inferiority of the pulp and partly due to difficulties connected with its treatment4 ,probably cultivation of the plant for the sake of its fibre instead of the sugar might give better results4 7#f7 ,peat4--,the attempts made to utilise peat for paper-making are probably fresh in the minds of those paper-makers interested in the production of wrappers and boxboards4 ,the nature of peat1 however1 is such as to exclude the hope of making any useful article4 ,the material has been exploited by companies in ,austria1 ,ireland1 and ,canada on a fairly large scale1 with but a limited amount of success4 7#g7 ,cotton-seed ,hulls4--,many patents have been taken out for the chemical treatment of cotton-seed waste and having for their object the removal of the particles of seed hulls1 so as to obtain a pure cotton pulp4 ,the scheme sounds attractive1 but there are so many conditions which have to be taken account of that the commercial success of any undertaking based on the use of cotton-seed hulls is very questionable4 ,the fact is that the hulls have a market value quite apart from the possibility of their application to paper-making1 and this initial cost would prevent paper-makers from buying the material owing to the large quantity necessary for the manufacture of one ton of pure pulp4 7#h7 ,apocynum4--,this plant is said to be utilised to some extent by the ,russian ,government in the manufacture of bank notes1 the plant being cultivated at ,poltava4 ,this is an instance of the particular application of a fibrous material in limited quantities1 a proposition which is always feasible in the case of special requirements4 7#i7 ,cornstalk4--,this fibre has been chiefly exploited in ,america1 experts having been attracted by the enormous quantities of cornstalk available in the several wheat-producing ,states4 ,the manufacture of paper pulp from this material on a large scale has yet to be established4 7#aj7 ,japanese ,paper ,fibres4--,in ,eastern countries a great number of fibrous plants are utilised in small quantities for the manufacture of special papers4 ,it is obvious that in these ,eastern countries the employment of fibres which are not cultivated in large bulk is readily possible when the question of price obtained for the paper and the cost of production are considered4 ,of such fibres may be mentioned the ,mitsumata and ,kodzu1 easy of cultivation and giving a good yield of material per acre of ground4 ,the waxed papers used for stencils in duplicating work on the typewriter are made from these fibres4 ,the paper ,mulberry is also a well-known fibre2 while a third species particularly valuable for thin papers is the ,gampi4 7#aa7 ,antaimoto ,fibre4--,the bark of this shrub is utilised in ,madagascar in very small quantities for local purposes and possesses little interest for paper-makers4 7#ab7 ,refuse ,hempstalk4--,the suggestion of the use of this material comes from ,italy1 the hempstalk having been experimented with at ,san ,cesario ,mill4 ,this also is a fibre of a local interest only4 ,the percentage of cellulose is very high1 being over #ej per cent4 7#ac7 ,papyrus4--,the revival of this celebrated material is of comparatively recent date4 ,it should be noted that the manufacture of papyrus as carried out by the ,egyptians1 by smoothing out layers of bark in order to utilise them as sheets of paper1 and the present day proposals which involve the production of paper pulp from papyrus1 are two entirely different propositions1 and the success of the old ,egyptian method cannot be referred to as any assurance of success for the production of paper from papyrus along modern lines4 ,the exploitation of this fibre must follow the lines of modern research and commercial investigation1 and its value1 if any1 could then be established4 7#ad7 ,pousolsia4--,this is a fibre of the same family as hemp and ramie4 ,the value of this material is at present unknown1 but the ultimate fibre appears to possess a most extraordinary length4 ,very little information is available at present as to its value for paper-making4 7#ae7 ,bamboo4--,this material has been before the paper trade for many years1 having first been exploited seriously by ,mr4 ,thomas ,routledge in #ahge4 ,since that date a good deal of work has been done in connection with the fibre1 but not until recently has the investigation been made of a sufficiently extensive character to enable paper-makers to form some conclusions as to the best methods of obtaining a reliable paper pulp4 ,the researches of the writer in ,india go to prove that with any fibre it is necessary to take into account all the factors likely to affect the final cost of the paper pulp delivered to any given paper mill4 ,the figures given in a report recently published1 ,the ,manufacture of ,paper and ,paper ,pulp in ,burma1 show the necessity of thorough investigation into all the points likely to affect the final results1 viz41 the price at which the paper pulp can be sold in ,england1 assuming that the fibre in question is suitable for the manufacture of paper4 99 99 99 99 99 ,examination of ,fibres4--,the exact chemical analysis of a new fibre is necessary in order to establish completely its value for textile and paper-making purposes1 but the investigation of the suitability of the fibre for paper-making may be simplified by simple reduction of the raw material with caustic soda4 ,the following process is sufficient for all practical purposes3-- ,condition of ,sample4--,a record should be made of the general appearance of the sample1 its condition and the amount available for the investigation4 ,any information available as to the source of supply and the growth of the plant should also be noted4 ,preparation of ,sample4--,the material is cut up into small pieces4 ,the most convenient appliance for this purpose is a mitre cutter as used by picture-frame makers4 ,if the sample is a piece of wood1 sections one inch thick cut across the grain of the wood are most suitable1 as they can be readily cut up into thin flakes by this machine4 ,moisture in ,sample4--,a small average sample should be dried at #ajj ,c4 for the determination of moisture4 ,treatment with ,caustic ,soda4--,about two hundred grams of the raw material is closely packed into a small digester or autoclave and covered with a solution of caustic soda having a specific gravity of #ajej4 ,a perforated lead disc should be placed above the sample in the digester to prevent any of it from floating above the level of the solution4 ,the material should be digested for five or six hours at a pressure of #ej lbs4 ,the conditions of treatment here given will need to be varied according to the nature of the fibre4 ,some materials can be readily converted into pulp with weaker liquor and at a lower pressure1 while others will require prolonged treatment4 ,these conditions must be varied according to judgment or according to the effects produced by the conditions already set out4 ,unbleached ,pulp4--,the contents of the digester are emptied out into an ordinary circular sieve provided with a fine copper wire bottom1 having a mesh of about sixteen to the inch4 ,the sieve is immersed in water and the contents partially washed with hot water4 ,the partially washed material is squeezed out by hand and tied up in a strong cloth and then kneaded thoroughly by hand in a basin of water which is repeatedly renewed until the fibre is thoroughly washed4 ,the process of kneading at the same time reduces the fibre to the condition of pulp4 ,the water is carefully squeezed out of the pulp by hand1 and the moist pulp is then divided into two equal parts1 the first of which is made up into sheets of any convenient size1 care being taken that none of the fibre is lost4 ,these sheets are then dried in the air and preserved as samples of unbleached pulp1 a record being made of the weight produced4 ,bleached ,pulp4--,the second portion of the moist pulp is mixed with a solution of bleach1 the strength of which has been accurately determined by the usual methods4 ,the amount of bleach added should be about #bj per cent4 of the weight of air-dry fibre present in the moist sample of pulp4 ,the pulp should be bleached at a temperature not exceeding #ch ,c41 and when the colour has reached a maximum the amount of bleach remaining in solution is ascertained by titration with standard arsenic solution4 ,in this way the amount of bleaching powder required to bleach the pulp is determined4 ,the product is then made up into sheets of pulp which are dried by exposure to air and subsequently weighed4 ,yield of ,pulp4--,the percentage yield of finished pulp obtained from the raw material is determined from the figures arrived at in the experiment described1 and the weight of raw material necessary to produce one ton of bleached pulp is readily calculated4 ,examination of ,bleached ,fibre4--,the fibre should be carefully examined under the microscope and a record made of general microscopic features1 especially with reference to the length and diameter of the fibres1 and the proportion of cellular matter present1 if any4 ,sample of ,paper4--,it is only in the case of short-fibred material similar to esparto and straw that sheets of paper capable of giving comparative results as to strength can be made4 ,the figures obtained with fibrous materials of this kind are only comparative1 because it is possible in practice to make a much stronger sheet of paper when the material is beaten properly under normal conditions4 ,a similar investigation should be made by submitting the fibre to treatment with bisulphite of lime1 that is to say1 if the fibre lends itself to such a process4 ,a lead-lined digester is necessary1 and the solution employed is bisulphite of lime prepared according to the directions given on page #afj4 ,the preparation of sulphite pulp requires more attention than the manufacture of soda pulp4 ,it is most important that the digester should be absolutely tight in order to prevent the escape of any free sulphurous acid gas1 and the contents of the digester must be heated slowly until the maximum pressure has been reached4 ,,chapter ,,iii ,,the ,,manufacture ,,of ,,paper ,,from ,,rags ,illustration3 ,,fig4 #f4--;,a ,rag ,sorting ,house4 ,the word rag is used to designate a very wide range of raw material suitable for conversion into paper4 ,in the case of high-class hand-made writing papers only the best qualities are employed1 such as new linen and cotton cuttings from factories1 or well-sorted rags of domestic origin4 ,the usual classification adopted by merchants who supply the paper mills is somewhat as follows3-- ,new white linen cuttings 7from textile factories74 ,new white cotton cuttings 7from textile factories74 ,fine whites 7domestic rags74 ,outshots 7a quality between fines and seconds74 ,seconds 7a grade inferior to fines74 ,thirds 7inferior and dirty well-worn rags74 ,coloured prints 7of all grades and colours74 ,fustians and canvas4 ,manila and hemp rope4 ,baggy1 gunny1 and jute4 ,the total amount of rag used in ,england for paper-making is not known4 ,the only figures available refer to rags imported2 and these cannot be regarded as a measure of consumption1 which could only be arrived at by first ascertaining the quantity of home rags used4 ,the imports of rag at stated periods are given in the appended table3-- ,,rags ,,imported ,,into ,,england4 ---------------------------------------- ------------------------ -- #ahgb4 #ahhb4 #ahib4 #aijb4 #aije4 ---------------------------------------- ------------------------ ,weight 7tons7 #bb1bed #ba1bjj #bc1jcb #ah1fib #bc1fha ,value #cgc1jce #cjc1cdi #bad1jfe #agc1gcb #bbd1bcb ---------------------------------------- ------------------------ ,sorting and ,cutting4--,all rags on arrival at the mill are carefully sorted4 ,this process is conducted entirely by women1 who sort and cut up the rags at special tables provided with cutting knives curved in shape similar to a scythe4 ,these are fixed at an angle in the centre of the table1 with the back towards and in front of each work-woman4 ,the top of the table is made of thick coarse wire so that some of the dirt and foreign impurities may fall through4 ,all buttons1 hooks and eyes1 pins1 leather1 pieces of rubber1 and other articles are carefully removed1 while seams and hems are also opened out4 ,the rags are cut into slips #c-e inches long and then recut crosswise1 and thrown into suitable baskets or receptacles standing round the table1 by which means the sorting operation is effectually carried out4 ,the care and attention given to the sorting is an important item in the manufacture of papers of uniform quality1 and in the best mills the sorting is carried out to such an extent that twenty or twenty-five grades are obtained4 ,illustration3 ,,fig4 #g4--;,a ,rag ,duster4 ,dusting4--,the rags are next passed through a machine which removes dirt4 ,this is a hollow cylindrical or conical drum having an external covering of coarse wire cloth1 which rotates inside a wooden box4 ,the shaft is provided with projecting spikes1 so that the rags are violently agitated in their passage through the machine4 ,the dirt and other impurities fall through the wire on to the floor of the room1 while the clean rags are discharged from the lower end of the drum4 ,the loss in weight varies according to the condition of the rags4 ,with good materials the loss may only be #a-b per cent41 while with dirty common rags the loss during cleaning and dusting may amount to #aj per cent4 ,illustration3 ,,fig4 #h4--;,a ,rag ,cutter4 ,boiling4--,the further purification of the rags is effected by a chemical treatment1 viz41 boiling at a high temperature with alkaline substances1 which process removes fatty1 glutinous1 and starchy matter from the material4 ,illustration3 ,,fig4 #i4--;,interior of ,paper ,mill for ,hand-made ,paper 7,r4 ,batchelor ,sons74 ,for this purpose a spherical digester is used1 generally #g-i feet diameter1 and capable of holding #b-b tons of rag4 ,the boiler or digester is filled with dusted rags1 and the requisite amount of alkaline solution added4 ,the manhole is then closed1 and steam admitted through the hollow trunnions until the pressure reaches #bj or #cj lbs41 at which pressure the boiling is continued for three to six hours according to requirements1 the digester rotating slowly the whole time in order that the rags may be evenly and thoroughly boiled4 ,illustration3 ,,fig4 #aj4--,view of a ,rag ,boiler1 showing connections4 ,the liquor employed for boiling is a solution of caustic soda1 carbonate of soda1 or milk of lime4 ,in the case of caustic soda the amount required varies from #e to #aj per cent4 of the weight of rag4 ,caustic soda is preferable to lime1 because it acts upon the grease and other fatty matters1 forming a soluble compound which is freely removed in the subsequent process of washing4 ,many paper-makers1 however1 use milk of lime1 carefully strained through fine cloth1 almost exclusively4 ,considerable experience and skill are necessary in this operation in order to avoid injury to the fibre not only as regards its strength1 but also its colour4 ,washing4--,when the rags have been sufficiently boiled1 the steam is turned off and the pressure allowed to fall4 ,this can be effected quickly by blowing off from a valve fixed at the bottom of the boiler opposite to the manhole4 ,the cover is removed from the boiler and the boiler slowly rotated in order that the contents may be discharged into a tank placed below4 ,the black liquor1 as it is called1 is then drained away from the rags1 which are immediately subjected to a preliminary washing4 ,the process of washing must be carried out in a thorough manner in order to remove all soluble compounds1 which if left would cause an unnecessary waste of bleach in the subsequent stages of purification4 ,there are many schemes employed for washing1 most of them being devised with the idea of using a minimum quantity of water4 ,the most general practice1 in the absence of special machinery1 is the preliminary treatment in the tank below the digester1 followed by a more complete washing process in a machine known as a breaking engine4 ,this apparatus is a shallow oval-shaped vessel with circular ends1 divided lengthwise by a partition called a mid-feather1 which1 however1 does not extend the full length of the apparatus4 ,in one of the two channels into which the vessel is thus divided a heavy roll is fitted1 which is provided with a number of steel knives4 ,on the floor of this channel there is fixed a bed-plate1 also provided with projecting knives which are parallel with the knives in the roll4 ,the distance between the knives in the roll and those in the bed-plate may be altered as required by means of an adjusting screw4 ,in the other channel of the breaking engine there is fitted a drum-washer1 which serves for the removal of the dirty water from the machine4 ,this drum is divided into sections by means of partitions which reach from the centre to the circumference4 ,the surface of the drum-washer consists of a fine brass wire cloth supported by a coarser material placed underneath4 ,illustration3 ,,fig4 #aa4--;,a ,breaking and ,washing ,engine4 ,the breaking engine is half filled with clean water1 and the rags are thrown into the engine until it is suitably filled4 ,the rotation of the heavy roll causes the mixture of rags and water to circulate round the vessel1 the floor of which is so constructed that the pulp is drawn between the roll and bed-plate and discharged over the backfall1 which is that portion of the sloping floor behind the bed-plate4 ,the drum-washer rotates with its surface in contact with the mixture in the engine1 so that the dirty water passes through the wire cloth and is caught in the curved sections or buckets inside the drum and discharged into a trough adjacent to the centre1 and thereby conveyed away from the engine4 ,clean water is allowed to run into the vessel at one end while the dirty water is discharged by means of the drum-washer4 ,at the same time the rags are broken up by means of the knives on the roll1 so that when the rags are sufficiently washed1 a process which usually occupies four hours1 they are also partially disintegrated4 ,bleaching4--,the clean disintegrated rag is next bleached by means of ordinary bleaching powder solution4 ,bleaching powder is a substance prepared by the action of chlorine gas on dry slaked lime1 resulting in the formation of a compound which has the property of bleaching or whitening vegetable matters4 ,the clear solution obtained by treating the powder with water is utilised by the paper-maker for bleaching the rag pulp4 ,various methods are used for this purpose4 ,sometimes the requisite volume of clear bleach liquor is added to the pulp in the breaker1 and the material kept in constant circulation until the operation has been completed4 ,in other cases the broken pulp is transferred to a potcher1 which is a vessel similar in shape to the breaker1 but merely provided with paddles for keeping the pulp in circulation1 and bleached by the addition of chloride of lime solution4 ,another method frequently adopted is to discharge the pulp from the breaker1 immediately after the addition of the bleach1 into brick or cement tanks1 allowing the bleaching action to proceed spontaneously without prolonged agitation4 ,in some instances the process is hastened by adding dilute sulphuric acid to the pulp after the bleach liquor has been run in1 or by heating the mixture with steam4 ,for high-class papers such devices as this are seldom resorted to1 as experience shows that the colour of pulp bleached by drastic methods does not maintain a high standard4 ,the pulp is then thoroughly washed in order to remove every trace of residual bleach1 and also the soluble compounds which have been formed during the operation4 ,very large quantities of water1 clear and free from suspended dirt1 are necessary4 ,in some mills any excess of bleach is neutralised by the use of an antichlor such as sodium hyposulphite1 or sodium sulphite1 but the best results are undoubtedly obtained when the quantity of chemicals used is kept at a minimum4 ,if the pulp is bleached in a breaker or potcher1 the washing is effected by the aid of the drum-washer4 ,with pulp treated in steeping tanks1 fresh water is allowed to percolate or drain slowly through the mass4 ,,electrolytic ,,bleaching4 ,the substitution of a sodium hypochlorite solution for the ordinary calcium hypochlorite solution obtained from common bleaching powder has been the aim of specialists for many years4 ,as early as #ahea a patent was taken out by ,charles ,watt for decomposing chlorides of the alkali metals and the formation of hypochlorites4 ,it was not until #ahhf that a practical method was devised for producing an electrolysed solution of salt1 but in that year ,hermite introduced a continuous process in which an electrolysed solution having a strength of three grammes chlorine per litre was passed continuously into the potcher4 ,many patents for the electrolysis of salt have been taken out during the last twenty years1 of which the ,bird-,hargreave process is in operation in ,england1 the ,rhodin process in ,america1 the ,siemens and ,halske in ,norway1 and the ,oettel and ,haas apparatus in ,germany4 ,the figures relating to the latter apparatus may be mentioned as typical of the present condition of electrolytic bleaching4 ,the apparatus consists of a narrow rectangular trough divided into a number of chambers through which a solution of brine flows at a constant and steady rate4 ,the electric current is passed through the solution by suitable electrodes1 the temperature being kept down by means of a cooling coil4 ,the cost of producing the bleach liquor as given by the inventors of the apparatus from the results of actual working are shown in the following table3-- ,,table ,,giving ,,analysis ,,of ,,cost ,,for ,,producing ,,bleach ,,liquor4 ,capacity of tank #gej litres #aff gallons4 ,strength or density of brine #ae ,baum1 or #bc ,twaddell4 #bhf lbs4 of common salt required for #aff gallons4 ---------------------------------------- ----------------------- ,hours worked #b #d #f #h #aj #ab ,grammes of chlorine per litre produced #dce #gch #ii #abdb #adca #afbj ,temperature ,c4 of brine during operation #bj #ba #bj #ba #bj #bj ,ampres of #aaj volts #ee #ej #df #eb #dg #dc ,power in h4p4 hours #af #ca #de #fa #ge #hi ,cost of the h4p4 at #bb;d4 per h4p4 #as4 #as4 #as4 hour #c;d4 #f;d4#aj;d4 #a;d4 #d;d4 #g;d4 ,cost of salt #as4 #as4 #as4 #as4 #as4 #as4 #f;d4 #f;d4 #f;d4 #f;d4 #f;d4 #f;d4 ,total cost #as4 #bs4 #bs4 #bs4 #bs4 #cs4 #i;d4 #j;d4 #d;d4 #g;d4 #aj;d4 #a;d4 ,total chlorine obtained in kilos4 #cbfb #eece #gdbe #icae #ajgcb #abaej ,cost of chlorine per kilo4 #ff;d4 #d;d4#c;d4#cd;d4 #cb;d4 #c;d4 ,salt used per kilo4 chlorine #ce #bj #ae #ab #aj #i ---------------------------------------- ----------------------- ,the above costs have been estimated on prices as follows3-- ,coal #ajs4 per ton4 ,salt #abs4 per ton4 ,after #ab hours the #aff gallons 7#gej litres7 are converted into electrolytic bleach liquor containing #bf lbs4 of active chlorine 7#abae kilos474 ,beating4--,although the rags are reduced by the breaking engine to a condition of fibrous lint1 called half-stuff1 they are not fit for conversion into paper4 ,they have to be beaten in special machinery until a complete separation of the single fibres has been effected1 and this process is rightly regarded by many paper-makers as the most important stage of manufacture4 ,illustration3 ,,fig4 #ab4--,oettel and ,haas' ,apparatus for the manufacture of ,electrolytic ,bleach ,liquor4 ,the beating engine is similar in construction to the breaking engine1 but there are certain essential differences in arrangement and manipulation4 ,there is usually no drum-washer2 the roll contains a large number of knives which are fixed in clumps or sets of three round the circumference2 the lowering of the roll upon the bed-plate is carefully watched and controlled1 and the desired effects are only obtained by strict attention to the condition of the pulp during the whole process4 ,illustration3 ,,fig4 #ac4--,the ,hollander ,beating ,engine4 ,the beater is first partially filled with water1 and the drained half-stuff added gradually until the furnish1 a convenient term applied to the contents of the engine1 has the proper consistency1 which varies according to the nature and quality of paper required4 ,the mass is circulated steadily round the engine by the action of the beater roll1 which is lowered from time to time until the distance between the knives on the roll and those on the bed-plate has been set to the desired adjustment4 ,this lowering of the roll and its proper adjustment call for the greatest care4 ,influence of the ,beating4--,the importance of this operation can easily be judged from one or two specific examples4 ,in the case of rag papers the two extremes of variation are represented by the ordinary blotting paper on the one hand and a hard strong writing paper known as a loan on the other4 ,now the great difference in these papers may be traced to the careful selection of the rag and the treatment in the beater as the two primary causes of the final results4 ,for blotting papers it is essential that the rags should be old and tender4 ,in the beating operation subsequent to the usual boiling and bleaching processes the half-stuff is beaten quickly with sharp knives1 the roll being lowered soon after the engine is filled1 so that the beating is finished in about one to one and a half hours4 ,for the strong writing paper new strong rags are selected4 ,in the beating process the knives used are dull1 the roll is lowered slowly and cautiously1 and the beating goes on for eight to ten hours4 ,the effect of such difference in treatment is easily seen by examination of the fibres of the papers under the microscope4 ,in the first case the fibres appear short with clean cut ends1 the shape little distorted1 the structure well defined1 bearing a strong resemblance to the unbeaten material4 ,in the case of the well-beaten paper the ends of the individual fibres appear to be drawn or frayed out1 the fibres do not possess the sharp well-defined outline characteristic of blotting paper2 they are partly split up into fibrill which lie together in a confused mass4 ,in the blotting paper these effects are produced because the knives being sharp cut up the material quickly1 and in the writing paper because the dull tackle tends to draw out the fibres and tear them up lengthwise4 ,the practical result is a spongy1 soft1 and bulky blotting and a hard1 strong1 heavy writing paper4 ,of course the great difference between a blotting and a writing paper is not all due to this one operation1 but is obtained by a series of operations1 of which one of the most important is1 however1 the beating4 ,colouring the ,paper4--,the pulp is brought to any desired tint by the addition of mineral pigments or aniline dyes to the contents of the engine4 ,the latter soluble dyes1 however1 are seldom used for high-class rag papers4 ,prussian blue1 ultramarine1 and smalts are chiefly used for this purpose1 giving toned blue1 azure1 and blue laid papers4 ,illustration3 ,,fig4 #ad4--,the ,hand ,mould showing ,frame and ,deckle4 ,making the ,paper4--,the beaten pulp1 when duly prepared1 is run from the engine into store tanks known as stuff chests1 ready for the actual manufacture4 ,the pulp properly diluted with water is strained through special screens to remove any insufficiently beaten material and any impurities present1 after which it is run off into the vat1 a square-shaped vessel built of wood or stone4 ,the apparatus used in forming the sheets is called a hand mould4 ,the mould is a rectangular frame of mahogany upon which is stretched tightly a fine wire cloth1 the surface of the latter being kept flat by a coarser wire cloth fixed underneath1 supplemented by wedge-shaped pieces of wood4 ,a second frame called the deckle fits on to the mould in such a manner as to form a shallow tray1 the bottom of which is the fine wire cloth4 ,the vatman takes up the mould with both hands and dips it into the vat full of pulp in a slanting position1 drawing it through the stuff towards him in a peculiar manner and lifting it out from the vat with a definite quantity of the mixture in the frame4 ,as the water drains away from the pulp1 through the wire cloth1 he imparts a shaking motion to the mould in order to cause the fibres to felt properly1 this felting or interlacing of the fibres being an essential feature in the manufacture of a good sheet of paper4 ,when the water has drained away sufficiently from the pulp1 the vatman removes the deckle from the mould and passes the latter over to the coucher1 who takes the mould1 reverses it1 and presses the contents1 which may now be described as a wet sheet of paper1 down on to a damp piece of felt1 by which means the paper is transferred to the felt4 ,he returns the mould to the vatman1 who meanwhile has made another sheet with a duplicate mould1 and then1 having laid a second felt upon the wet sheet of paper1 he proceeds to transfer the next sheet of paper to the second felt4 ,this process is continued until a pile is formed consisting of wet sheets of paper alternated with pieces of felt4 ,the pile is at once submitted to great pressure in the hydraulic press1 and the excess water slowly forced out1 while at the same time the sheets are compressed and thus closed up1 as it is termed4 ,when all the excess water has been removed as far as possible1 the pile is taken away and the sheets of damp paper taken out1 the felts being placed in one pile ready for further use1 and the sheets of paper in a second ready for the next process4 ,the papers are put back into the press without felts between the sheets and left for some time4 ,in most cases the sheets are turned round or mixed in with the sheets of another pile1 before pressing4 ,in this way any unevenness or irregularity in the sheets is counteracted and a more uniform result obtained4 ,when these changes are repeated several times the paper acquires an even texture and becomes firm and hard4 ,drying the ,paper4--,the sheets are hung up in the loft1 as the drying room is called1 upon poles or ropes4 ,the moisture gradually evaporates1 and the paper is thus dried by exposure to air4 ,in winter it is necessary to warm the air in the loft1 as the air is then saturated with moisture4 ,in lofts of limited capacity the air is heated in order to hasten the process1 but the best paper is allowed to dry naturally1 as by this means the shrinkage is gradual and a maximum strength is attained4 ,illustration3 ,,fig4 #ae4--;,apparatus for ,sizing ,paper in continuous ,rolls4 ,sizing the ,paper4--,the dried paper as it leaves the loft is termed ,waterleaf because1 being unsized1 it readily absorbs water1 and therefore before it can be used it must be sized4 ,for this purpose it is dipped into a solution of gelatine1 an operation described as tub-sizing or animal-sizing1 the former term being used on account of the tub in which the size is kept1 and the latter on account of the fact that the gelatine is made from animal matter such as hides1 cartilage1 hoofs1 and other refuse4 ,animal ,size4--,this is prepared from hide pieces1 skins1 and the like by a simple process1 which1 however1 requires a good deal of care in order to obtain the best results4 ,the material is first thoroughly washed in plenty of clean water1 and then heated with a definite quantity of water in a steam jacketed copper pan4 ,the pieces slowly dissolve until a solution of gelatine is produced1 and after the dirt and impurities have settled to the bottom of the pan the clear liquid is drawn off into store vessels4 ,there are many details of a technical character to be attended to in the manufacture of good gelatine1 and as the process is expensive1 considerable attention is demanded at this stage in the completion of a sheet of paper4 ,the dry sheets of paper are sized by the simple expedient of dipping1 or by the passage of the paper through a long trough4 ,in the first case the workman takes up a number of sheets and dips the bunch into a vat of size at the proper temperature1 about #ajj ,fahrenheit4 ,he then allows the surplus size to drain off1 and the sheets are submitted to a slight pressure in order to remove the excess of gelatine that will not drain off4 ,in the second case a different method is adopted in that the sheets of paper are carried by travelling felts through a bath of heated size1 the excess gelatine being removed by the action of rubber or wooden rollers through which the papers are passed before leaving the apparatus4 ,the papers are quickly and evenly sized by this method1 which is now most generally used4 ,glazing4--,when the sheets of paper are quite dry they are ready for glazing1 a process which turns the dull rough surface of the sized sheet into a highly polished smooth surface fit for use4 ,the sheets are placed singly between copper or zinc plates1 and a pile of these passed several times through heavy iron rollers1 great pressure being applied to the latter during the operation4 ,illustration3 ,,fig4 #af4--;,a ,supercalender4 ,the amount of polish imparted by this plate-glazing process1 as it is termed1 can be varied considerably4 ,with a light pressure and few rollings1 the sheet of paper can be turned out having a fairly smooth surface1 and without a conspicuously shiny appearance4 ,by employing a great pressure and repeated rolling a much higher surface is attainable4 ,if the plates are hot a still higher finish is possible4 ,machine-made rag papers are glazed usually by means of the supercalender1 which is a stack of alternate steel and paper rolls placed one above the other in a vertical position4 ,the reel of paper passes between these rolls and becomes highly surfaced4 ,this operation effects many changes in the paper1 besides imparting a good finish4 ,the thickness of the sheet is reduced by about #dj per cent41 the fibres being compressed much closer together4 ,the tensile strength of the paper is also materially increased1 and in every way the paper is improved4 ,moderation is essential in this as in everything1 because excess of glazing weakens a paper1 rendering it brittle and liable to crack when folded4 ,laid and ,wove ,papers4--,when certain papers are held up to the light and carefully examined it will be noticed that they appear to contain delicate transparent lines running parallel with one another at equal distances of about an inch1 and that these are intersected by similar transparent lines running at right angles1 which are much closer together4 ,such papers are known as ,laid ,papers1 and the peculiar formation of the transparent lines is due to the construction of the mould used in the making4 ,the wire surface of this mould consists of a number of somewhat stout wires placed about one inch apart1 interwoven with finer wires running across and at right angles1 which are threaded much closer together4 ,when the mould is dipped into the vat and withdrawn1 the water drains away from the under surface of the wire1 and the moist pulp settles down on the upper surface2 but since the coarser wires project a little from the finer threads1 the paper is slightly thinner along those wires1 though to an almost infinitesimal extent1 with the result that on drying the sheet appears to contain transparent lines4 ,wove papers are so called from the nature of the mould used4 ,the surface of the mould in this case consists of fine wires equally distributed1 being woven in such a manner that the wires are equidistant from one another1 as in ordinary wire gauze4 ,a wove paper1 on being examined in the light1 simply shows a number of small diamond-shaped spaces1 which in the majority of instances are difficult to detect4 ,the ,watermark4--,the transparent device observed in many papers when held up to the light is known as the watermark1 a term probably derived from the conditions existing at the time the sheet of paper is made on the mould4 ,the effect is produced by means of a raised design sewn or soldered to the surface of the mould1 the design being fashioned out of fine wire4 ,illustration3 ,,fig4 #ag4--,the ,first ,watermark in ,paper4 ,when a mould thus fitted with the design is dipped into a vat of pulp and lifted out1 the water falls through the wire1 and the pulp sinks down on to the surface of the mould1 forming a replica1 so to speak1 of the design1 which is easily seen when the dry paper is held up to the light1 because the paper is thinner just at those points where the wires forming the design come into contact with the wet pulp4 ,some of the watermarks are very elaborate and interesting4 ,a familiar illustration of a beautiful design of this description is to be found in the ,bank of ,england notes4 ,as a general rule the ordinary watermark consists of a mere trade term such as ,vellum1 ,zenobia1 or of the name of the manufacturer1 such as ,j4 ,whatman1 ,r4 ,batchelor1 and so on4 ,in the earlier days of paper-making many highly interesting designs were used1 and some of these are still extant4 ,in fact many of the names by which certain standard sizes of paper are known owe their origin to the watermarks employed4 ,the earliest known watermark bears the date ,a4,d4 #acja1 being in the form of a globe and cross1 as shown4 ,of equal interest are those designs from which certain papers are called foolscap1 crown1 pott1 post1 royal1 columbier1 and so on4 ,the watermarks are now little used1 but the terms are still retained1 as indicating the size of the sheet4 ,,microscopic ,,features ,,of ,,cotton ,,and ,,linen ,,fibres4 ,the cotton fibre is about #cj mm4 long1 with an average diameter of #jbe mm4 of tube-like shape1 and having a prominent central canal4 ,there are no cross markings on the cell walls1 and the ends of the fibre are rounded off into a somewhat blunt point4 ,it exhibits a marked tendency to twist itself1 especially if dry1 and this peculiarity is readily observed with the raw material4 ,the process of paper-making alters the characteristic structure of the fibre very greatly4 ,the ends of the fibre are seldom to be seen2 the curious twist is less prominent1 and the fibres are torn and destroyed4 ,the effect of the beating process1 for example1 on cotton is easily to be noticed by comparing the fibres of a blotting paper under the microscope with the fibres of a bank or loan paper4 ,the distortions produced by prolonged beating renders the determination of the exact percentage of cotton in a rag paper rather difficult1 but the features to be looked for are the absence of pores1 cross markings1 the existence of a central canal1 striations produced in many cases on the cell walls parallel to the length of the fibre4 ,the structural features are more readily observed when the fibres are stained with a suitable reagent4 7,see page #ga47 ,illustration3 ,,fig4 #ah4--;,cotton4 ,the linen fibre has an average length of #bg mm4 with a diameter of #jb mm4 ,the raw flax is very different from raw cotton and is easily distinguished4 ,the fibre is slender in shape1 having thickened knots at regular intervals throughout its length1 the general appearance of which may be compared to a stick of bamboo4 ,the central canal of the fibre is extremely narrow1 running like a small thread through the length of the fibre4 ,the cell walls are further marked by numerous pores1 which appear as small dark lines running from side to side1 but not meeting in the centre4 ,illustration3 ,,fig4 #ai4--,linen4 ,in the treatment necessary for making paper these characteristics are largely destroyed1 and while it is quite easy to ascertain that a paper is of linen1 or of cotton1 or that a paper is mainly cotton with a small percentage of linen1 yet there are conditions under which it is difficult to determine the exact percentage of cotton or linen in a rag paper4 ,if1 for example1 a paper contains nearly equal quantities of cotton and linen1 the exact proportions cannot be determined closer than #aj per cent41 especially in well-beaten papers4 ,,reagent ,,for ,,staining ,,fibres4 ,preparation4--,dissolve #ba grams potassium iodide and #ja grams iodine in #e c4c4 of water4 ,mix this solution with a solution containing #bj grams of dry zinc chloride in #aj c4c4 of water4 ,allow the mixture to stand2 pour off the clear liquid into suitable bottles4 ,,coloration ,,produced4 ,cotton1 linen1 hemp4--,wine red4 ,esparto1 straw and wood cellulose4--,bluish violet4 ,mechanical wood1 unbleached jute4--,yellow4 ,manila hemp4--,blue1 bluish grey to yellow4 ,,chapter ,,iv ,,esparto ,,and ,,straw ,,esparto ,,papers4 ,the value of ,esparto for the manufacture of high-class printing and medium quality writing paper is well known4 ,this material has qualities which cannot readily be obtained from other fibres1 such as rag and wood pulp4 ,it is chiefly used in papers required for lithographic printing1 books1 and art illustration1 since it gives a sheet having a good surface and one which is soft and flexible4 ,the grass is obtained from ,spain1 ,morocco1 ,algeria1 ,tunis1 and ,tripoli1 in which countries it grows wild1 requiring very little cultivation4 ,the condition of the crop is improved by proper treatment1 and in districts where the grass is cut for export as a paper-making material attention is given to cultivation4 ,the plant grows to a height of three or four feet1 and when mature the long blades of grass curl up into the form of a cylinder resembling a piece of wire4 ,the leaf consists of two parts1 the stalk and a sheath1 which are easily separated when harvested4 ,the grass is pulled up by hand and stacked into heaps in order that it may be dried by the heat of the sun1 after which process it is carefully picked over for the removal of all extraneous matter and impurities4 ,it is then graded1 the best sorts being kept for weaving1 and the remainder being sold for paper-making4 ,it is packed up into large bales of about #d cwt4 capacity1 compressed into small bulk by powerful presses1 and shipped to ,england4 ,esparto ,pulp4--,the first process in the manufacture of the paper is cleaning4 ,the bundles of grass are opened up1 shaken out1 and put through a willowing machine4 ,this consists of a hollow conical drum1 the outer surface of which is a coarse wire cloth4 ,inside the drum is fitted a shaft provided with wooden teeth1 and as the grass passes through it is tossed about and the dust removed4 ,the clean grass is conveyed by travelling belts to the digester house4 ,for the production of a high-class paper the grass is often examined by girls1 who stand on either side of the travelling conveyer and take out any coarse root ends and foreign material not removed by the willowing machine4 ,boiling4--,the object of submitting esparto to chemical treatment is to obtain a pure paper-making fibre known as cellulose4 ,the composition of this raw material is shown by the following analysis3-- ,spanish ,esparto4 ,cellulose #dhbe ,water #ich ,aqueous extract #ajai ,pectous matter #bfci ,fatty matter #bjg ,ash #cgb ------ #ajjj ------ ,yield of dry cellulose obtained in actual practice from good raw material #de to #dh ,by boiling the esparto with caustic soda under pressure for a stated time1 the non-fibrous constituents are removed1 leaving the cellulose in a more or less pure form according to the severity of the chemical treatment4 ,illustration3 ,,fig4 #bj4--;,an ,esparto ,duster4 ,in practice the grass is packed tightly into upright stationary digesters and a definite quantity of caustic soda solution added1 the amount of chemical used being equal to #ae-ah per cent4 of the weight of grass packed into the digester4 ,the form of digester almost universally employed is that known as the ,sinclair's vomiting boiler1 which is constructed so that a continuous circulation of the liquid is maintained by means of what are called vomit pipes4 ,these are fitted to the sides of the digester in such a manner that the caustic soda solution circulates from the bottom of the digester1 up through the vomit pipes1 and is discharged downwards upon the contents of the boiler through a perforated plate fixed in the upper part of the digester4 ,the requisite quantity of caustic soda solution is placed in the digester1 and steam admitted into the bottom of the vessel while the grass is being thrown in4 ,in this way a much larger weight of grass can be boiled at one operation1 since the bulk is greatly reduced when the grass has become thoroughly soft and wet4 ,illustration3 ,,fig4 #ba4--,sinclair's ,vomiting ,esparto ,boiler4 ,when the boiler is loaded the inlet is closed up and steam turned on to the full pressure of about #dj or #ej lbs41 this being maintained for a period of about four hours4 ,the non-fibrous constituents of the esparto are gradually dissolved out by the caustic soda1 and when the operation is completed the black liquor is run off from the digester into large store tanks1 and the esparto grass which remains in the digester is then completely washed until the soda is almost entirely washed out4 ,illustration3 ,,fig4 #bb4--;,a ,porion ,evaporator4 ,the conditions for boiling and bleaching esparto are varied by the paper-maker as circumstances require4 ,a maximum yield of fibre is obtained when the least possible quantity of caustic soda is used1 but a larger percentage of bleaching powder may be necessary to ensure a well bleached pulp4 ,the use of an excess of caustic soda is probably the general practice for several reasons1 amongst which may be noted the advisability of guarding against irregularities in the quality of the esparto1 and consequent insufficient boiling1 as well as the advantage of having some free caustic in the spent liquors to prevent the furring up of the tubes of the evaporating apparatus in the soda recovery department4 ,the following experiments1 given by a contributor to the ,paper ,trade ,review some years ago1 are interesting as showing the effect of varying proportions of caustic soda used per unit of grass3-- ,,experiments ,,re ,,yield ,,of ,,air-,,dry ,,bleached ,,pulp ,,from ,,oran ,,esparto4 ,air-dry ,pulp containing #aj per cent4 water4 ---------------------------------------- --------------------------- ,esparto4 ,soda ,liquor4 ,conditions of ,dry ,boiling4 ,weight ,pulp ,bleach- ---------------------------------------- -- of on ,dry ing ,no4 ,wt4 ,volume1 ,per ,time4 ,temp4,pres-,air-dry,esparto4,powder4 taken4 ,c4,c4 cent4 ,hours4 ,c4 sure4,pulp4 ,per ,per ,grams4 ,na#b,o4 ,lbs4,grams4 cent4 cent4 ---------------------------------------- ------------------------ #a #bjj #hjj #aeh #c #adb #ee #hgcj #dcfe #bie #b #bjj #hjj #bac #c #adb #ee #hjfg #djcc #ahe #c #bjj #hjj #bfi #c #adb #ee #gbjj #cfjj #aje ---------------------------------------- ------------------------ ,no4 ,no4 of ,experiment4 ,,practical ,,data ,,calculated ,,from ,,experiments4 ---------------------------------------- -------------------------- ,boiling4 ,weight of #fj per cent4 ,bleaching ,for ,one ,ton of ,no4-----------,esparto to,caustic ,soda ,powder ,esparto used4 ,time4 ,pres-give #a tonrequired to required to ---------------- ,hours4sure4 ,pulp4 ,digest ,bleach #a ton #fj per ,bleach- ,lbs4 ,cwts4 ,esparto4 ,air-dry ,pulp4 cent4 ing ,cwts4 ,cwts4 ,caustic4,powder4 ,lbs4 ,lbs4 ---------------------------------------- ------------------------ #a #c #ee #deh #dcj #ebf #baj #bfj #b #c #ee #die #fbg #cci #bhb #aef #c #c #ee #eee #hij #aif #ceh #gi ---------------------------------------- ------------------------ ,no4 ,no4 of ,experiment4 ,recovery of ,spent ,liquor4--,as it is possible to recover #ge to #hj per cent4 of the soda originally used in digesting the esparto1 the washing of the boiled grass is conducted on scientific principles in order to ensure a maximum recovery of soda at a minimum cost4 ,the recovery is effected by evaporating down the black liquor1 together with the washing waters1 to a thick syrupy mass1 which can be burnt4 ,the organic and resinous constituents of the esparto which have been dissolved out by the caustic soda1 forming the soluble soda compounds1 ignite readily1 and during combustion the organic soda compounds are converted more or less completely into crude carbonate of soda4 ,it is obvious1 then1 that the cost of recovery depends mainly on the quantity of weak washing water which has to be evaporated4 ,consequently methods are devised by means of which the grass is thoroughly washed with as little water as possible1 and some of the methods are very ingenious4 ,the spent liquors and washing waters are evaporated to a small bulk in a vacuum multiple effect apparatus1 and the thick liquid mass obtained by evaporation is burnt either in a rotary furnace or on an ordinary hearth4 ,every precaution is taken to effect this operation with a minimum quantity of coal4 ,the burning off of this mass results in the formation of a black substance which is taken away from the furnace and allowed to char or slowly burn until the impure white soda ash1 or carbonate of soda1 is obtained4 ,two systems of recovery are in general use1 which deserve a brief notice3-- ,direct ,evaporation4--,the liquors may be evaporated to a small bulk ready for incineration by treatment in long shallow pans or furnaces1 the heat necessary for the process being obtained mainly from the combustion of the thick concentrated liquor4 ,the most familiar type of this form of apparatus is the ,porion evaporator4 ,illustration3 ,,fig4 #bc4--,scott's ,multiple ,effect ,evaporator4 ,the combustion of the concentrated liquor is started by a coal furnace at one end of the apparatus4 ,the thick viscous mass catches fire and burns with a fierce flame1 and the heat is utilised in evaporating the weaker liquors which flow continuously through shallow brick troughs1 the surface of which is freely exposed to the heat and flames from the hearth where the organic soda compounds produced in the boiling of esparto are being incinerated and converted into soda ash4 ,under suitable conditions this evaporator is most economical in its results4 ,it can be erected cheaply1 and when all the heat is fully used in every possible direction it can be worked at a low cost compared with the more modern multiple effect evaporators4 ,vacuum ,multiple ,effect ,evaporation4--,advantage is taken of the fact that water boils at a lower temperature in a vacuum than at the ordinary pressure of the atmosphere4 ,there are many forms of apparatus based on this principle1 amongst which the most recent is ,scott's evaporator4 ,the black liquor from the boilers is pumped through tubes heated externally by high-pressure steam4 ,the liquor is passed into a chamber in which a slight vacuum is maintained1 so that immediately on entering1 the liquor parts with a good deal of water in the shape of steam4 ,the steam liberated is utilised in producing further evaporation of the partially concentrated liquor1 and this operation is repeated several times until the concentration is effected to the desired point4 ,in most cases the actual incineration of the thick liquor is carried out in a rotary furnace when such an apparatus as this is used4 ,,evaporation ,,table4 ,showing the volume of liquor obtained by evaporating #a1jjj gallons of weak black lye of density d to a higher density ,d4 ---------------------------------------- -------------------------- ,lower ,higher ,density ,d 7,twaddell7 at #ajj ,f4 ,density d ---------------------------------------- ------------- 7at #ajj ,f474 #bj4 #be4 #cj4 #ce4 #dj4 #de4 #ej4 #ee4 #fj4 ---------------------------------------- ------------------ #b #ajj #hj #fff #ega #ej #ddd #dj #cfc #ccc #c #aej #abj #ajj #heg #ge #fff #fj #ede #ej #d #bjj #afj #acccaadcajj #hhh #hj #gbg #fff #e #bej #bjj #afffadc #abe #aaajajj #iji #hcc #f #cjj #bdj #bjj #agadaej #acccabj #aji #ajj #g #cej #bhj #bcccbjj #age #aeeeadj #abg #aaff #h #djj #cbj #bfffbbhfbjj #aggfafj #adeeaccc #i #dej #cfj #cjj #beg #bbe #bjj #ahj #afceaej #aj #ejj #djj #ccccbhf #bej #bbb #bjj #ahahafff ---------------------------------------- ------------------ ,,example3--#a1jjj gallons of weak liquor at a density of #g ,twaddell are reduced to a volume of #bjj gallons having a density of #ce ,twaddell1 or to a volume of #adj gallons with a density of #ej ,twaddell1 by evaporation4 ,preparation of ,caustic ,soda4--,the crude soda ash recovered from previous boiling operations is dissolved in large lixiviating tanks and extracted with hot water4 ,the clear solution obtained after all impurities have been allowed to settle is pumped up into the causticising tanks1 where it is converted into caustic soda1 the loss due to the amount of soda not recovered being made up by the addition of ordinary soda ash4 ,the causticising pans are large circular iron vessels usually #i feet diameter and #h or #i feet deep1 into which a known volume of the recovered carbonate of soda solution is placed4 ,a weighed quantity of ordinary quicklime is then put into a perforated iron cage which is fixed inside the causticising pan at such a level that the whole of the lime is immersed in the solution4 ,the liquor is kept in constant circulation by means of an agitator and heated to boiling point1 with the result that the chemical reaction sets in1 the carbonate of soda being converted into caustic soda and the lime being thrown out as chalk4 ,when the operation is completed1 the steam is turned off and the chalk allowed to settle4 ,the clear liquor is carefully strained off and pumped up into store tanks from which the required quantities are drawn off into the digesters as circumstances demand4 ,washing4--,the grass which has been partially washed in the digester is dug out by the workmen and discharged through a manhole fitted on one side of the digester near the bottom4 ,it is then conveyed in any convenient manner to the breaking engine1 in which the grass is more completely washed4 ,this important machine has already been described on page #ec4 ,the floor of the vessel slopes slightly upward towards the front of the roll and falls suddenly behind the roll1 in order to promote a circulation of the contents of the engine round and round the vessel4 ,a definite weight of boiled grass is thrown into the engine together with a large quantity of fresh water4 ,the circulation of the roll draws the mixture of pulp and water between the knives1 breaking it up and at the same time discharging it behind the beater roll1 and producing a continuous circulation of the mixture in the two sections of the vessels4 ,the dirty water is continuously removed from the vessel by means of a drum-washer4 ,this is a large hollow drum1 the outer surface of which consists of a fine wire cloth1 the interior of the washer being fitted with specially curved scoops4 ,the drum-washer is lowered until it is half immersed in the mixture of pulp and water1 and as it rotates the dirty water finds its way through the wire cloth1 being caught up by the internal scoops and discharged through a pipe to a drain outside the breaking engine4 ,at the same time fresh water is run into the vessel at one end1 and the continuous washing of the pulp thus effected4 ,bleaching4--,the clean boiled grass is bleached by means of a solution of chloride of lime4 ,there are several methods used for this purpose1 each of which has special advantages of its own1 though this is largely a question of local conditions3-- 7,a7 ,the pulp can be bleached in the washing engine directly the grass has been sufficiently cleaned4 ,in this case the flow of fresh water is stopped and as much water as possible removed by means of the drum-washer4 ,the drum-washer is then raised out of the pulp and a known volume of bleaching powder solution corresponding to a definite weight of dry powder is added to the contents of the breaking engine4 ,the amount used depends on the quantity of dry grass in the breaking engine1 the usual proportion being #h to #aj per cent4 on the calculated air-dry weight of raw grass4 ,as the stuff circulates round the engine the colour gradually changes from dark yellow to white4 ,the process is sometimes hastened by blowing a small quantity of steam into the mixture and thereby raising its temperature4 ,considerable care must be exercised in using heat1 because pulp bleached quickly by this means is liable to lose colour at the later stages of manufacture4 ,when the pulp has been bleached to the required extent1 the drum-washer is again lowered into contact with the bleached pulp1 and the latter is thoroughly washed so as to be quite free from traces of bleach and other soluble impurities4 7,b7 ,esparto is often bleached in a ,tower bleaching engine which consists of a tall cylindrical vessel of #i feet diameter1 and #ae or #af feet deep1 at the bottom of which is fixed a small centrifugal pump4 ,the boiled grass together with sufficient water and clear bleaching powder solution is placed in the engine2 the centrifugal pump draws the mixture from the bottom of the vessel and discharges it1 by means of a large external pipe1 direct into the top of the vessel1 where1 as it falls1 it comes into contact with a circular baffle-plate1 which distributes the pulp evenly over the surface of the mixture in the vessel4 ,a continuous and rapid circulation is thus maintained1 and the process is said to be very effective4 ,the bleached pulp is subsequently washed free from any traces of bleach4 7,c7 ,esparto is frequently bleached by the steeping process4 ,in this case the pulp is washed in the breaking engine1 mixed with the required quantity of bleach1 and at once discharged through the outlet pipes of the engine into large brick tanks1 where the bleach is allowed to act quietly upon the boiled grass4 ,this method produces a pulp of good colour and is economical4 ,whichever process of bleaching is adopted1 it is necessary to remove all the by-products formed during the process1 as these soluble by-products if left in the mixture produce a lowering of colour4 ,the presence of small traces of bleaching powder solution can be detected by the use of starch and potassium iodide test papers4 ,if a handful of the pulp after bleaching1 when squeezed out1 does not turn the test paper violet or blue1 then the absence of any free bleach is taken for granted4 ,the slightest trace of bleach will turn such test papers blue or violet according to the amount present4 ,this is the test usually applied by the men in charge of the bleaching operations4 ,making ,sheets of ,esparto ,pulp4--,for convenience in handling1 it is usual to work up the washed and bleached pulp into the form of moist sheets4 ,this is effected on a machine known as a presse-pte1 an apparatus which closely resembles the wet end of a paper machine4 ,it consists of a set of flat strainers or screens1 a horizontal wire similar to the paper machine wire1 provided with deckles1 the usual couch rolls1 and press rolls4 ,illustration3 ,,fig4 #bd4--;,a ,presse-pte for ,esparto ,pulp4 ,the pulp diluted with water is passed through the screens and on to the horizontal wire1 where it is formed into a moist sheet1 the water draining away from the wire1 and also being removed by vacuum pumps4 ,the thick sheet of pulp is carried through the couch rolls and press rolls1 being finally wound up on a wooden roller at the end of the machine4 ,in this moist condition it is ready for use in the mill4 ,dry ,esparto ,pulp4--,when the bleached pulp is intended for export a more elaborate machine is used--to all intents and purposes a paper-making machine--by means of which the continuous sheet of moist pulp is dried and cut up into smaller sheets of suitable size4 ,these dried sheets are packed up in bales containing #b cwt4 or #d cwt4 of dried pulp1 then wrapped in hessian and bound with iron wires4 ,other ,methods4--,since the yield of esparto pulp from the raw material is less than #ej per cent4 and it requires #de cwt4 of grass to make one ton of finished pulp1 methods have been devised for treating the grass in the green state in the districts where it is grown1 but so far nothing has been done on a large scale4 ,the isolation of the cellulose by alkaline treatment in the cold has been suggested1 but the method never passed beyond the experimental stage4 ,this process was indeed first mentioned by ,trabut1 who many years ago considered that the removal of non-fibrous constituents from fresh grass could be readily accomplished by the less drastic treatment of the esparto with alkaline carbonates of soda and potash at ordinary temperatures4 ,the production of esparto pulp by bacteriological fermentation is an idea of later date4 ,according to the inventor1 the grass is crushed mechanically by means of rollers and then immersed in sea water inoculated with special bacillus obtained from esparto1 and gradually resolved into cellulose and soluble by-products by fermentation which is complete in about eleven days4 ,the commercial value of this idea has not yet been demonstrated4 ,,esparto ,,pulp3 ,,microscopical ,,features4 ,the pulp of esparto when examined under the microscope is easily recognised1 first by the characteristic appearance of the long slender cylindrical-shaped fibres1 and secondly by the numerous cells always present4 ,these cells consist of cuticular vessels with serrated edges1 and also of small pear-shaped seed hairs1 the shape of which is a ready means of identifying esparto4 ,an examination of the transverse section of the raw material indicates the source of these pear-shaped vessels4 ,test for ,esparto in ,papers4--,paper containing esparto fibre may be tested by means of a weak solution of aniline sulphate4 ,the suspected paper is gently heated in the test reagent1 and if esparto is present the paper turns a rose-red or pink colour1 the depth of colour being a measure of the amount of esparto4 ,most of the modern book papers are prepared from chemical wood pulp and esparto mixed in varying proportions1 and while this test can be used as a means of detecting a small or a large proportion of esparto1 a microscopical examination is required for a more accurate estimation4 ,the proportions used by the paper-maker depend upon the weighing out of the wood pulp and esparto more or less accurately1 while the microscopical test is based upon the relative proportions as represented by the volume of fibres of each class on the glass slip placed under the microscope4 ,since the wood pulp consists of a number of broad flat ribbon-like fibres1 and the esparto of small cylindrical fibres1 considerable practice is necessary in making a proper analysis of the two constituents in paper4 ,illustration3 ,,fig4 #be4--;,esparto ,pulp4 ,,straw4 ,the use of straw for the manufacture of paper was first brought prominently into notice about the year #ahjj by ,matthias ,koops1 who published a book printed on paper made from straw1 but it was not until #ahfj that this material was used in any large quantity4 ,illustration3 ,,fig4 #bf4--;,a ,cylindrical ,digester for ,boiling ,fibre4 ,straw is now converted into a bleached paper pulp for news and printings1 and is also utilised for the manufacture of straw boards4 ,the production of a white paper pulp from straw is carried out in a manner similar to that used in the case of esparto fibre1 viz41 by digestion with caustic soda under pressure and subsequent bleaching4 ,as the straw contains considerable quantities of siliceous matter1 the chemical treatment necessary to reduce the material to paper pulp is more severe1 a stronger solution of caustic soda being used1 and the process of digestion being carried out at a higher temperature4 ,for the best quality of straw cellulose1 the material is cut up into small pieces by machines which resemble an ordinary chaff-cutter1 and the knots taken out by a separating machine4 ,in most cases1 however1 the whole straw is simply cut up into small lengths of about one to two inches long1 and placed at once in the digester4 ,when the straw is contaminated with foreign weeds1 sand1 husks1 and similar substances1 as is usually the case1 it is carefully hand-picked by girls1 who remove these impurities1 which tend to produce particles of unbleached matter in the finished pulp4 ,the expense of this preliminary cleaning process is more than compensated for by the enhanced value of the bleached straw pulp4 ,digesting4--,the cut straw is boiled in rotary cylindrical or spherical vessels1 stationary upright boilers of the vomiting type being seldom employed because the circulation of the caustic soda liquor does not take place freely with straw packed in the latter4 ,as the material is very bulky1 some of the liquor is first put into the boiler and the steam admitted while the straw is being thrown in4 ,by this means the straw is softened and reduced in bulk1 so that a larger quantity can be added before the digester is quite full4 ,the full amount of caustic soda is then made up by further additions of liquor1 and the contents of the digester heated by high-pressure steam for four to six hours4 ,the conditions of treatment are shown by the following trial3-- ,amount of straw #e1fjj lbs4 ,caustic soda1 #bj per cent4 #a1abj lbs4 ,the caustic soda was added in the form of a liquor1 having a volume of #b1jab gallons and a specific gravity of #ajee4 ,time of boiling #e hours4 ,pressure #fj lbs4 ,washing4--,the boiled straw is discharged into large tanks placed below the digester and washed with hot water1 the smallest possible quantity being used consistent with complete washing in order to prevent the accumulation of large volumes of weak lye4 ,the spent liquor and washing waters are drained off into store tanks and evaporated in a multiple effect apparatus by the same process as that used for esparto pulp4 ,the last washings are usually run away because the percentage of soda in them is too small to pay for the cost of recovery4 ,the final washing of the straw pulp is completed by the use of a breaking engine or potcher4 ,as straw pulp contains a large proportion of cellular matter which cannot be regarded as true fibres1 there is always a danger of considerable loss in yield if the use of the breaking engine is extensively adopted1 because the short cells escape through the meshes of the drum-washer4 ,the washing is most economically effected in the tanks if a good yield of pulp is required4 ,separating out ,knots4--,the broken pulp from the breaking engines is diluted with large quantities of water and pumped over sand traps in order to remove knots and weeds which have resisted the action of the caustic soda4 ,these traps consist of long shallow trays1 perhaps sixty to eighty yards long1 one yard wide1 and nine inches deep1 containing boards which stretch from side to side1 sloping at an angle1 and nailed to the bottom of the trays4 ,the dilute pulp flows through the trays1 leaving the heavy particles1 knots1 and foreign matter behind the sloping boards1 and finally passes over the strainers1 which retain any large coarse pieces still remaining4 ,making ,sheets of ,pulp4--,the mixture from the strainers contains a large excess of water which has to be removed before the pulp can be bleached4 ,for this purpose a wet press machine 7see page #ajc7 or a presse-pte 7see page #he7 is employed1 and the wet sheets of pulp are then ready for bleaching4 ,bleaching4--,the process by which the pulp is bleached is exactly similar to that used for treating esparto4 ,from #ahgj to #ahij large quantities of straw were used for the manufacture of newspaper in conjunction with esparto and wood pulp1 but the price of the material was gradually advanced so that it could not be used with advantage1 especially as the production of wood pulp gave a material which was much cheaper1 and which could be utilised at once without chemical treatment4 ,in the manufacture of newspaper the tendency during recent years has been to make the paper mill operations as mechanical as possible and to dispense with the preliminary operations which are essential for the manufacture of half-stuff1 the chemical processes being left in the hands of the pulp manufacturers4 ,the manufacture of straw cellulose is now practically confined to ,germany1 but small quantities of the bleached straw cellulose are imported because the pulp imparts certain qualities to paper which improve it1 notably in making cheap printing papers harder and more opaque4 ,,microscopical ,,features ,,of ,,straw4 ,the paper pulp obtained from straw consists of a mixture of short fibres together with a large proportion of oval-shaped cells4 ,the fibres are short and somewhat resemble esparto1 but the presence of the smaller cells is a sure indication of the straw pulp4 ,the fibres themselves closely resemble the fibres of esparto1 but as a rule the latter are long slender fibres1 while the straw fibre is very often bent and twisted or slightly kinked4 ,illustration3 ,,fig4 #bg4--,straw4 ,the only method of distinguishing between straw and esparto is by examination with the microscope4 ,there is no chemical reagent known which will produce a colour reaction on a paper containing straw that will serve to distinguish it from a paper containing esparto4 ,if such papers are gently heated in a weak solution of aniline sulphate a pink colour is slowly developed1 the intensity of which is to some extent a measure of the amount of straw or esparto present4 ,straw and esparto are usually described in text-books under one heading1 partly because the fibres possess strong resemblances in physical and chemical constitution1 and partly because the methods of manufacture are identical4 ,at the same time the qualities of the two pulps are so different that they cannot be used indiscriminately1 the one for the other4 ,straw cellulose cannot be utilised in the place of esparto1 particularly for light bulky papers4 ,hence in magazine and book papers containing a fibre which gives a pink coloration with aniline sulphate it is fairly safe to assume that esparto pulp is present4 ,,chapter ,v ,,wood ,,pulp ,,and ,,wood ,,pulp ,,papers ,,the ,,manufacture ,,of ,,mechanical ,,wood ,,pulp4 ,wood is converted into pulp suitable for the manufacture of paper by methods which produce two distinct varieties4 ,the first is mechanical wood pulp1 so called because it is made by a purely mechanical process4 ,the second is termed chemical wood pulp from the fact that the material is submitted to chemical treatment4 ,ground ,wood and ,cellulose4--,the two varieties of pulp are sometimes distinguished by the use of the terms ground wood and cellulose4 ,in the former case the description implies a product consisting of pulp obtained by grinding wood into a fibrous condition1 while in the second the word suggests a purified chemical product freed from the resinous and non-fibrous constituents found in wood4 ,this is1 in fact1 the essential difference1 for mechanical wood pulp consists of fibres which have been torn away from wood by means of a grindstone2 it differs but slightly in chemical composition from the original raw material and contains most of the complex substances natural to wood4 ,chemical wood pulp1 on the other hand1 consists of fibre isolated from wood in such a manner that the complex non-fibrous substances are more or less entirely removed4 ,the difference between these two pulps is shown in the following approximate analysis of spruce wood1 and of the pulp derived from it4 ,the composition of the mechanical pulp is practically identical with that of the wood itself4 ,,composition ,,of ,,spruce ,,wood1 ,,and ,,of ,,chemical ,,wood ,,pulp 7,,spruce74 ----------------------------------- -- ,wood ,chemical 7,spruce74,wood ,pulp4 ----------------------------------- ,cellulose #ecj #hhj ,resin #ae #je ,aqueous ,extract #be #je ,water #abj #hj ,lignin #cje #be ,ash #je #je ------------------- #ajjj #ajjj ----------------------------------- ,the use of mechanical wood pulp is generally confined to the manufacture of news1 common printings and packing papers1 cardboards1 and boxboards4 ,it possesses very little strength1 quickly discolours when exposed to light and air1 and gradually loses its fibrous character4 ,the chemical wood pulp is a strong fibre1 from which high-class papers can be manufactured1 the colour and strength of which leave little to be desired4 ,species of ,wood4--,the woods most commonly used for the manufacture of wood pulp belong to the order ,conifer1 or cone-bearing trees4 ,in ,europe the spruce and silver fir are the chief species1 while in ,america spruce1 balsam1 pine1 and fir are employed4 ,the harder woods1 such as hemlock1 beech1 larch and others1 are not converted into pulp by the mechanical process4 ,timber ,operations4--,the trees are cut down in the early part of winter by gangs of men specially trained to the work4 ,the organisation of a lumber camp when the operations are of an extensive character is very complete and carefully arranged1 every detail being attended to in order to get out the wood as cheaply and expeditiously as possible4 ,the branches and small tops are removed from the trees when they are fallen1 and the trunks cut into logs of #ab1 #ad1 or #af feet in length1 and afterwards piled up on the banks of the nearest river1 or on the ice1 ready for the breaking up of the winter4 ,as soon as the ice breaks up and the rivers become navigable the logs are floated down to their destination1 in some cases hundreds of miles from the scene of operations4 ,where rivers are not available the timber is brought out by horses or bullocks1 or by means of a light railway4 ,log ,cutting4--,as the timber arrives at the mill it is carefully measured1 both as to its diameter and length1 in order that a record may be kept of the quantity used4 ,some of the logs are piled up in the storeyard for use in the winter1 and the remainder converted into pulp day by day4 ,the logs are first cut into short pieces about #b feet long by means of a powerful circular saw1 the arrangements for this work being devised so as to keep down the cost of labour as much as possible4 ,all waste pieces are thrown aside to be utilised as fuel4 ,barking4--,the bark on the logs is removed in one or two ways4 ,much of it is knocked off during the transfer from the forest to the mill1 but even then the wood requires to be cleaned4 ,in ,norway and ,sweden the wood is treated in a tumbler or a barker1 while in ,america and ,canada the use of the tumbler is practically unknown4 ,the barker consists of a heavy iron disc fitted with knives1 usually three in number1 which project from the surface of the disc about half or three-quarters of an inch4 ,the barker rotates in a vertical position1 and the short pieces of wood are brought one by one into contact with the disc in such a manner that the bark is shaved off by the knives4 ,the machine is provided with conveniences for pressing the wood against the disc and for turning the logs as they are barked4 ,illustration3 ,,fig4 #bh4--;,a ,pair of ,barkers for removing ,bark from ,logs of ,wood4 ,the machine is encased in a strong cast-iron cover1 and all the bark shaved off is carried away by the strong current of air set up by the rapid motion of the disc1 and subsequently burnt4 ,the tumbler system is quite different4 ,in this case the short pieces are thrown into a large circular drum with hot water1 and the bark taken off by the friction of the pieces as the drum rotates4 ,the loss of material is of course less in this process1 but the wood is not cleaned quite so effectively4 ,illustration3 ,,fig4 #bi4--,view of ,horizontal ,grinder 7,a71 with ,section 7,b74 ,the wood at this stage can be used either for the manufacture of mechanical or chemical pulp4 ,as a general rule the pieces are taken indiscriminately for either process1 but sometimes the wood is sorted out1 the clean stuff free from knots and blemishes being reserved for high quality chemical pulp4 ,grinding4--,the main feature of the grinding process is the attrition of the wood when held against the surface of a rapidly revolving grindstone1 the fibres as they are rubbed off being instantly carried away from the stone by a current of water4 ,a complete description of the machines used and the modifications of the process practised by manufacturers is impossible in this book1 but the following points will be sufficient4 ,the machine consists of a large grindstone about #ed inches in diameter1 and #bg inches thick4 ,it rotates in a vertical or in a horizontal position at a high speed4 ,the stone revolves inside a casing which is provided with a number of pockets1 so called1 into which the pieces of wood are thrown at regular intervals1 as fast as the wood is ground by the friction of the stone4 ,a continual stream of water playing upon the surface of the stone washes away the pulp into a tank or pit below the machine4 ,the quality of the pulp may be varied by the conditions under which it is made4 ,by limiting the proportion of water so that the wood remains in contact with the stone for a longer time the temperature of the mass in the pockets rises4 ,such hot ground pulp1 as it is termed1 is tough and strong4 ,when the fibres are washed away from the stone as fast as they are produced the temperature does not rise1 and cold ground pulp is made1 which is not characterised by the somewhat leathery feel of the pulp made at the higher temperature4 ,the surface of the stone plays an important part also4 ,if the stone is smooth the wood is rubbed away slowly1 but if the surface has been roughened and grooved by means of a special tool the fibres are torn away quickly4 ,in the first case the pulp comes from the stone in a finely-ground state and in a uniform condition1 while in the second the pulp is coarse and chippy4 ,the output of the machine is1 however1 much increased by the use of sharp stones and by the application of considerable pressure to the blocks of wood4 ,illustration3 ,,fig4 #cj4--;,a ,vertical ,grinder for making ,hot ,ground ,mechanical ,wood ,pulp4 ,screening4--,the mixture of water and pulp leaving the grinder falls into a tank below the stone1 all large chips being retained by means of a perforated plate4 ,the finer pulp1 still too coarse for use1 is then pumped to the screens1 which serve to remove all chippy and coarse fibres and produce a uniform material4 ,the shaking sieve consists of a shallow tray1 the bottom of which is a brass plate or series of plates perforated with small holes or slits4 ,the pulp flows on to the tray1 which is kept in a state of violent agitation1 the fine pulp passing through the holes and the coarser pieces working down to the lower edge of the tray into a trough which carries them away4 ,the flat screen is somewhat different in construction1 but the principle of separation is the same4 ,it consists of brass perforated plates forming the bottom of a shallow cast-iron tray1 continually agitated by means of cams fixed to the under surface of the trays4 ,illustration3 ,,fig4 #ca4--;,centrifugal ,screen for ,wood ,pulp4 ,the centrifugal screen is a cage made of finely perforated brass sheeting which revolves at a very high rate of speed inside a circular cast-iron vessel4 ,the pulp flows into the interior of the cage1 the fine fibres being forced through the screen by the centrifugal action of the machine1 and the coarse material is retained4 ,illustration3 ,,fig4 #cb4--,section of ,centrifugal ,screen for ,wood ,pulp4 ,wet ,pressing4--,the pulp leaving the screens is mixed with such a large quantity of water that it is necessary to concentrate it4 ,this is effected by means of the wet press machine 7,fig4 #da74 ,the pulp and water are pumped into a wooden box in which revolves a large hollow drum1 the surface of this drum consisting of a fine wire cloth of about #fj or #gj mesh4 ,the drum is not entirely immersed in the mixture1 so that as it rotates the pulp forms a skin or thin sheet on the surface1 and the water passes away through the wire into the interior of the hollow drum4 ,the drum carries the thin sheet out of the box and above the level of the mixture until it comes into contact with an endless blanket or felt1 which is pressed against that part of the drum not immersed in the liquid4 ,by this means the thin sheet is transferred to the felt and carried between squeezing rolls to the finishing rolls4 ,the felt1 carrying on its upper surface the thin sheet of pulp1 passes between two rolls1 usually #af to #bj inches in diameter1 the upper being made of wood and the lower one of cast iron4 ,the pulp adheres to the upper drum and the felt passes round the lower drum back to the box containing the mixture of pulp and water2 the thin sheet is continuously wound on the upper roll until a certain thickness is reached4 ,when this occurs the attendant removes the thick sheet by a dexterous movement of a sharp stick across the face of the roll4 ,the wet pulp at this stage consists of #cj per cent4 air-dry pulp and #gj per cent4 of water4 ,hydraulic ,pressing4--,the sheets taken from the wet press machine are folded into a convenient shape and piled up1 coarse pieces of sacking being placed between the sheets4 ,at stated intervals the piles are submitted to pressure in hydraulic presses in order to remove further quantities of water1 which slowly drains away through the sacking4 ,in this way a mass of pulp in the form of thick folded sheets containing #ej per cent4 of dry wood pulp is produced4 ,the pieces of sacking are taken out and the sheets put up in bales of any required weight1 usually #b cwt4 or #d cwt4 ,,the ,,manufacture ,,of ,,chemical ,,wood ,,pulp4 ,most vegetable fibres are converted into pulp by alkaline processes1 that is by digesting the raw material with caustic soda and similar alkaline substances4 ,wood may be treated in two ways1 one of which is the ordinary soda process1 and the other an acid treatment requiring the use of sulphurous acid4 ,preparation of the ,wood4--,the logs of wood are cut up and barked exactly as in the case of mechanical pulp4 ,the short two-foot pieces are then cut up into small flakes about one inch square and half an inch thick by means of a machine known as a chipper4 ,this is similar in construction to a barker1 consisting of a heavy iron disc rotating at a high speed inside a stout cover4 ,the disc revolves in a vertical position1 and three projecting knives slice up the logs into flakes4 ,for this purpose the disc is provided with three slots which radiate from the centre towards the circumference for about #ab inches4 ,the knives can be adjusted so that they stand up through the slots and above the surface of the disc to any required distance4 ,in order to ensure uniformity in the size of the chips1 the practice is frequently adopted of sifting the wood leaving the chipper4 ,the sieve is a large skeleton drum1 the outer surface of which is made of a coarse wire cloth capable of passing all pieces of the size mentioned4 ,larger chips and pieces are retained in the drum as it revolves in a horizontal position and only fall out on reaching the extreme end of the machine4 ,the ,digesters4--,the object of boiling the wood under pressure with chemicals is to dissociate the valuable fibrous portion of the plant from the resinous and non-fibrous portion4 ,in this process the wood loses half its weight1 the yield of pulp being about #ej per cent41 and the remainder is dissolved out by the chemical solution4 ,the conditions of treatment are extremely varied in character1 the quality of the pulp produced varying in proportion4 ,the digesters are either spherical1 cylindrical1 or egg-shaped1 being constructed to revolve at a slow rate of speed1 or fixed permanently in an upright position4 ,spherical boilers are usually #i or #aj feet in diameter1 the cylindrical digesters being #dj or #ej feet high and #ab or #ae feet diameter1 the larger ones being capable of taking #bj tons of wood for each operation4 ,illustration3 ,,fig4 #cc4--,wood ,pulp ,digester1 partly in elevation1 partly in section4 ,for the alkaline process the interior of the digester does not require any special treatment1 but with the acid process the internal portion of the boiler is carefully lined with a thick layer of acid-resisting brick and cement4 ,the contents of the digester are heated by means of high-pressure steam1 which is blown direct into the mass or passed through a coil lying at the bottom of the vessel4 ,in the former case the steam is condensed by the liquor1 the volume of which is consequently increased1 while in the latter case the condensed steam is drawn off continuously from the pipes4 ,each system has its own particular advantages4 ,different ,kinds of ,chemical ,wood ,pulp4--,according to the method of treatment so the quality of the pulp varies4 ,the chemicals used1 the system of boiling1 the temperature of digestion1 the strength of the solutions1 the duration of the cooking period1 and1 last but not least1 the species of wood1 are all determining factors in the value of the ultimate product4 ,soda ,pulp4--,this is prepared by digesting wood with caustic soda in revolving boilers for eight or ten hours at a pressure of #fj to #hj lbs4 ,sulphate ,pulp4--,prepared by digesting the wood with a mixture of caustic soda1 sulphide of soda1 and sulphate of soda4 ,sulphite ,pulp4--,the process most generally adopted for the manufacture of wood pulp is the treatment of the material in brick-lined digesters with bisulphite of lime for eight to nine hours at a pressure of #hj lbs4 ,mitscherlich ,pulp4--,this is sulphite pulp prepared by digesting the wood at a much lower temperature and for a longer period than the ordinary sulphite4 ,the steam is not blown direct into the mass of wood1 and the pressure seldom exceeds #de or #ej lbs41 the time of boiling occupying #de to #ej hours4 ,so called from the name of the inventor4 ,sulphite ,wood ,pulp4--,this name is given to pulp prepared by digesting wood with solutions containing sulphurous acid1 or salts of sulphurous acid4 ,the acid is produced by burning sulphur or certain ores containing sulphur1 such as copper or iron pyrites1 in special ovens4 ,the most modern form of oven consists of a cylindrical cast-iron drum revolving slowly in a horizontal position on suitable bearings4 ,the sulphur is thrown at intervals1 or fed automatically1 into the oven1 the amount of air being carefully regulated to avoid the formation of sulphuric acid in the later stages of preparation4 ,the sulphur is also burnt in stationary ovens which consist of flat shallow closed trays4 ,illustration3 ,,fig4 #cd4--,view of ordinary ,sulphur-burning ,ovens4 ,the hot sulphurous acid gas passes through pipes and is cooled1 after which it is brought into contact with water and lime for the production of the bisulphite of lime4 ,this is accomplished by one of two methods as follows4 ,tower ,system4--,the cool gas is drawn into high towers usually built of wood1 #g or #h feet diameter1 which are filled with masses of limestone4 ,from tanks at the top of each tower a carefully regulated quantity of water flows down upon the limestone and absorbs the ascending column of gas1 this being drawn into the tower from the bottom4 ,the limestone is simultaneously dissolved1 and the liquid which flows out from the pipes at the bottom of the tower consists of lime dissolved in sulphurous acid1 together with a certain proportion of free sulphurous acid4 ,this is generally known as a solution of bisulphite of lime4 ,tank ,system4--,the somewhat costly tower system has in many cases been superseded by the use of a number of huge wooden vats1 #aj to #ab feet diameter and #h to #aj feet high4 ,these tanks are filled with water and a known quantity of slaked lime4 ,the gas is forced into the tanks by pressure or drawn through by suction1 and the conversion of the milk of lime into bisulphite of lime proceeds automatically4 ,in order to ensure complete absorption the gas passes through the tanks in series1 so that the spent gases leaving the vats do not contain any appreciable amount of sulphurous acid4 ,in order to obtain pulp of uniform quality it is necessary that the liquor should be of constant composition4 ,the formula differs in the various mills according to the conditions which are found most suitable4 ,sulphite ,digesters4--,the almost universal form of boiler employed in cooking wood by the sulphite process is a tall cylindrical vessel of about #ej feet in height1 and #ad to #ae feet internal diameter1 lined with acid-resisting brick4 ,this form of digester is capable of holding #bj tons of wood at one charge1 yielding #aj tons of finished pulp4 ,the chipped wood is discharged into the digesters from huge bins erected just above the openings to the digesters1 so that the latter can be filled without any delay and the requisite quantity of sulphite liquor added4 ,the manhole or cover is at once put on1 securely fastened1 and steam turned on gradually until the pressure reaches #gj or #hj lbs41 at which pressure the cooking is steadily maintained4 ,the progress of the operation is watched and samples of the liquor drawn from the boiler at intervals to be tested1 so that the boiling may be stopped when the results of the testing show the wood is sufficiently cooked4 ,there is no special difficulty in this operation1 provided the necessary conditions are observed4 ,it is important that the wood should be dry1 and that the proportion of sulphite liquor per ton of dry wood should be constant4 ,if the wood happens to be wet1 due allowance must be made for the excess water and a somewhat stronger liquor used in order to compensate for this4 ,other precautions of a similar character are observed in order to minimise the danger of an insufficiently cooked pulp4 ,washing4--,when the pulp has been boiled1 a process which generally occupies seven or eight hours1 the steam is shut off and the contents of the boiler blown out into large vats known as blow-out tanks1 the pressure of steam remaining in the digester being sufficient to empty the softened pulp in a few minutes4 ,much of the spent sulphite liquor1 now containing the dissolved resinous and non-fibrous portions of the original wood1 drains away from the mass in the tank1 and then copious supplies of clean water are added in order to wash out the residual liquors which it is essential to remove4 ,numerous other devices are employed to ensure the complete washing of the boiled pulp4 ,screening4--,the production of a high-class pulp necessitates proper screening to eliminate coarse pieces of unboiled wood and the knots1 the latter not being softened completely4 ,the methods adopted vary according to requirements4 ,for uniform clean pulp that can be bleached easily the material from the blow-out tanks is1 after washing1 mixed with large quantities of water and run through sand traps1 which consist of long shallow wide boxes provided with slanting baffle-boards to retain knots and large pieces of unsoftened wood1 the pulp thus partially screened being subsequently treated in the proper screening apparatus4 ,sometimes the washed pulp is sent direct to the screens and the well-boiled fibres sorted out by a system of graded screens1 which separate the completely isolated fibres from the bulk and retain the larger pieces1 these being broken down in a suitable engine and put back on the screens4 ,the machinery employed for screening chemical pulp is identical with that used for the treatment of mechanical wood pulp4 ,finishing4--,the ordinary sulphite pulp is worked up into the form of dry sheets for the market and not sent out in a wet state as the mechanical wood4 ,there are several practical disadvantages in preparing the latter in a dry condition which do not1 however1 occur with chemical pulp4 ,hence the pulp after being screened is not pressed but submitted to a different process4 ,from the screens the mixture of pulp and water1 the latter being present in large quantity1 is pumped into a concentrator1 or slusher1 as it is termed1 by means of which some of the water is taken out4 ,the slusher consists of a wooden box divided into two compartments by a vertical partition4 ,in the larger compartment a hollow drum covered with a fine wire cloth revolves1 the construction and purpose of which are precisely the same as that of the wet press machine used for mechanical pulp4 ,as the drum revolves the pulp adheres to the outer surface1 while the water passes through the wire cloth4 ,the drum is not completely immersed in the mixture1 so that the skin of pulp is brought out of the water by the rotation of the drum4 ,when this takes place the contact of a wooden or felt covered roll which revolves on the top of the drum causes the pulp to be transferred from the drum to the roll4 ,the wet pulp is continuously scraped off by an iron bar or doctor1 as it is called1 resting on the surface of the roll1 and it finally drops into the second compartment of the slusher in a more concentrated form ready for the drying machine4 ,drying4--,the mass of wet pulp from the slusher is conveyed into a circular reservoir or stuff chest1 which serves to supply the machine used for converting the pulp into dry sheets4 ,the machine is to all intents and purposes a ,fourdrinier paper machine1 and the process is similar to that used for the manufacture of paper4 ,the pulp flows in a continuous stream on to a horizontal endless wire1 which carries it forward as a thin layer2 the water drains through the meshes of the wire1 further quantities being removed by suction boxes1 which draw away the water by virtue of the vacuum produced by special pumps4 ,the wet sheet then passes between the couch rolls which compress the pulp1 squeezing out more water1 and then through press rolls1 which finally give a firm adherent sheet of pulp containing #gj per cent4 of water4 ,the sheet is dried by passing over a number of steam heated cylinders1 which cause all the moisture to evaporate from the pulp4 ,at the end of the machine the dry pulp is cut up into sheets of any convenient size1 and packed up in bales of two or four cwts4 ,mitscherlich ,sulphite ,pulp4--,this term is applied to sulphite wood prepared by submitting the chipped wood to a comparatively low pressure for a long period4 ,the wood is placed in the stationary upright form of digester with the requisite amount of liquor1 and the heating produced by the passage of steam through a leaden coil lying at the bottom of the digester1 so that the steam does not condense in the liquor but in the coil1 from which it is drawn off4 ,the pressure seldom exceeds #de lbs4 but the duration of the cooking is thirty-six to forty-eight hours4 ,the boiler is not emptied under pressure1 but the pulp is discharged from the digester after the pressure has been lowered1 and the manhole taken off4 ,the contents are usually shovelled out by the workmen4 ,the pulp is carefully washed1 screened and made up into wet sheets on the ordinary wet press machine4 ,this pulp is never dried on the ,fourdrinier like the common sulphite1 as its special qualities can only be preserved by the treatment described4 ,this pulp is particularly suitable for parchment papers1 grease proofs and transparent papers4 ,soda ,wood ,pulp4--,the chipped wood is boiled in stationary or revolving digesters for eight or nine hours at a pressure of #gj or #hj lbs4 ,a solution of caustic soda is employed1 about #af to #bj per cent4 of the weight of the wood being added to the contents of the digester4 ,live steam is blown direct into the mass1 and after the operation the spent liquor is carefully kept for subsequent treatment4 ,the pulp is washed in such a manner that the amount of water actually used is kept down to the smallest possible volume consistent with a complete removal of soluble matters4 ,this is done in order that the spent liquors may be treated for the recovery of the soda4 ,recovery of ,spent ,liquors4--,when wood is cooked by the soda and sulphate processes the solutions containing the dissolved organic matter from the wood can be evaporated1 and the original chemical recovered4 ,in the case of soda pulp the method of treatment is as follows3 the spent liquors and the washings are evaporated by means of a multiple effect vacuum apparatus to a thick syrup4 ,the concentrated liquor produced is then burnt in special furnaces1 all the organic matter being consumed1 leaving a black mass which consists mainly of carbonate of soda4 ,the mass is washed with water to remove the carbonate which is afterwards converted into caustic soda by being boiled with lime4 ,illustration3 ,,fig4 #ce4--,spruce ,wood ,pulp4 ,the spent liquors from the sulphite process have no value1 for they cannot be recovered by this method4 ,at present the whole of the sulphur used and the organic matter dissolved from the wood is lost4 ,this means the loss of about #bej to #cej lbs4 of sulphur and nearly #ej per cent4 of the weight of wood for every ton of pulp produced4 ,,wood ,,pulp2 ,,microscopic ,,features4 ,illustration3 ,,fig4 #cf4--,mechanical ,wood ,pulp4 ,mechanical and chemical pulps are readily distinguished under the microscope4 ,the former consists of fibres of irregular shape and size1 mixed with a large proportion of structureless particles1 all bearing evidence of having been torn apart and separated by mechanical methods4 ,the chemical pulp1 on the other hand1 consists of fibres isolated by a process which preserves them in perfect condition and form4 ,the pulp from the various woods can be differentiated by minute details in fibre structure1 some of the woods being determined from the presence of characteristic cells4 ,the use of aniline sulphate can also be resorted to1 and for microscopic work the most useful reagent is a mixture of zinc chloride and iodine4 ,this produces an intense yellow colour with mechanical pulp and a bluish colour with sulphite and other chemical wood pulps4 ,,the ,,daily ,,newspaper4 ,the newspapers of the present day are made almost exclusively of wood pulp4 ,the use of the latter material for paper-making has steadily increased from the date of its introduction about ,a4,d4 #ahgj1 when wood pulp was imported into ,england in considerable quantities4 ,news and cheap printings consist of mechanical and chemical wood pulps mixed in varying proportions determined chiefly by the price paid for the finished paper4 ,in some cases the proportion of mechanical wood pulp is as much as #he per cent41 though the average composition of a cheap wood paper is represented by the following proportions3 ,mechanical pulp1 #gj per cent42 sulphite pulp1 #bj per cent42 loading1 #aj per cent4 ,some idea of the enormous quantity of material used for the daily press may be judged from one or two examples4 ,a certain popular weekly newspaper having a circulation of one and a quarter million copies per week requires every week #acg tons of paper produced from #agj tons of wood4 ,a popular halfpenny newspaper boasting a circulation of about one-half million copies per day consumes #ahe tons of paper manufactured from #bcj tons of wood1 every week4 ,it is easy also from these facts to estimate the amount of timber which must be cut down to supply the demand for newspapers and cheap printings4 ,the manufacture of news calls for considerable skill and able management1 owing to the keen competition amongst the paper mills devoted to this class of paper4 ,the process as carried on in ,england is as follows3-- ,the mechanical pulp1 reaching the mill in the form of thick sheets suitably packed up into bales1 is first broken up again into moist pulp4 ,various machines are used for this1 such as ,wurster's kneading engine1 ,cornett's breaker1 or some similar contrivance4 ,an old potcher1 such as is used for the breaking and washing of rags1 makes a good pulp disintegrator4 ,the broken pulp is discharged into beating engines in any suitable or convenient manner and the right proportion of chemical wood pulp added in the form of dry sheets4 ,the beating process only occupies thirty to forty minutes in the case of the common news1 a marked contrast to the eight or nine hours required by rags4 ,china clay is added to the contents of the beater1 ten to twelve per cent4 being the general practice4 ,this is followed by a measured quantity of rosin size1 and after thorough incorporation the size is precipitated upon the fibres by means of alum4 ,in the commoner qualities of these papers the materials are added in the dry state1 but for finer grades of newspaper the china clay is mixed with water1 and carefully drained through a fine sieve before use4 ,the alum cake is also dissolved and treated in a similar manner in order to keep out dirt and coarse particles likely to produce holes in the paper4 ,the paper machine used for the manufacture of cheap printings is constructed to produce as much as #ajj to #ahj tons of finished paper per week1 every detail being arranged for a large output at a very high speed4 ,in the modern machine it is possible to produce paper at the rate of #dej to #eej feet per minute1 the width of the sheet being from #abj to #afj inches4 ,careful attention is paid to economy of every kind with regard to the power required for driving the machine1 the amount of steam consumed in drying the paper1 recovery of excess of fibre and china clay which escapes from the machine wire1 and similar details of a mechanical order4 ,illustration3 ,,fig4 #cg4--,the ,screens for removing ,coarse ,fibres from ,beaten ,pulp4 ,the beaten pulp1 after being sized and coloured1 is discharged into huge circular brick tanks1 or stuff chests1 two of which are found with each paper machine4 ,the supply of pulp and water for the machine is taken from one stuff chest while the second is being filled up from the beating engines1 in order to secure a mixture of constant composition4 ,illustration3 ,,fig4 #ch4--,the ,paper ,machine 7wet end showing wire74 ,the pulp is pumped from the stuff chest into a small regulating box placed above the machine wire1 and this box is kept full of beaten pulp so that the supply of pulp and water to the machine is perfectly constant4 ,the pulp1 diluted with the proper quantity of back-water1 is carefully strained through rotary screens and allowed to flow through a distributing box on to the machine wire1 where it rapidly forms a sheet of paper4 ,the excess of water1 together with a certain proportion of fine fibre and china clay1 falls through the wire1 and is caught below in a shallow box1 called the save-all4 ,this back-water1 as it is called1 is used over again for diluting the beaten pulp to the right consistency1 as already described4 ,the whole of the water obtained in this way is not all utilised in the regulating box1 and any surplus is pumped up continually into large store tanks and used in the beating engines for breaking down the dry pulp4 ,in many cases1 where a large quantity of water is used on the machine1 special methods have to be adopted for the recovery of all the fibre and clay1 which would otherwise be lost1 and there are many ingenious systems in use whereby this saving is effected4 ,the most usual practice is to allow the excess of water1 which contains from #h to #ae lbs4 of suspended matter per thousand gallons1 to flow through a series of brick tanks at a slow rate of speed4 ,the clay and fibre settle to the bottom of the tanks1 and the water passes away from the last tank almost clear and free from fibre and loading4 ,the drying of the moist paper leaving the press rolls of the machine is effected in the usual manner by means of drying cylinders4 ,on account of the great increase of speed at which the paper is produced1 the number of drying cylinders has also been increased1 and at the present time a machine of this description is provided with #bh or #cb cylinders1 the object being to dry the paper economically4 ,,mechanical ,,wood ,,pulp ,,in ,,paper4 ,the presence of mechanical wood pulp in paper is detected by means of several reagents1 which produce a definite colour when applied to a sheet of paper containing mechanical wood4 ,the depth of colour obtained indicates approximately the percentage present1 but considerable practice and experience is necessary to interpret the colour exactly4 ,a more reliable method of estimating the percentage of mechanical wood in a paper is by microscopic examination4 ,the reagents which can be used are-- 7#a7 ,nitric ,acid4--,this produces a brown stain on the paper1 but it is not a desirable reagent for ordinary office purposes4 7#b7 ,aniline ,sulphate4--,a solution of this is prepared by dissolving #e parts of aniline sulphate in #ajj parts of distilled water4 ,when applied to the surface of news a yellow coloration is produced1 more or less intense according to the amount of mechanical wood present4 ,it can only be used with white papers1 or papers very slightly toned4 7#c7 ,phloroglucine4--,this sensitive reagent1 which gives a rose-pink colour when brushed on to the surface of the paper1 is prepared by dissolving #d grammes of phloroglucine in #ajj c4c4 of rectified spirits1 and adding to the mixture #ej c4c4 of pure concentrated hydrochloric acid4 ,there are several other aniline compounds which give colour reactions of a similar character1 but they are not often used4 ,the phloroglucine reagent fails as a test for mechanical wood in papers which have been dyed with certain aniline colours1 for example1 metanil yellow4 ,paper which has been coloured with this dye will1 when moistened with the phloroglucine reagent1 give an intense pink colour1 even if no mechanical wood is present4 ,this is due to the fact that the dye itself is acted upon by the hydrochloric acid in the test reagent4 ,the same colour is produced on the paper with hydrochloric acid per se4 ,there is little difficulty in distinguishing between the colour arising from the presence of such a dye1 because the effect is instantaneous1 whereas the coloration due to mechanical wood develops gradually4 ,moreover1 the reaction due to the presence of metanil yellow gives a perfectly even coloured surface1 whereas with mechanical wood pulp the fibres appear to be more deeply stained than the body of the paper4 ,output of a ,paper ,machine4--,the quantity of paper which can be produced on the paper machine is readily calculated from the following data3-- ,speed of machine in feet per minute ,f ,nett deckle width in inches ,d ,width of sheet of paper in inches ,w ,length of sheet of paper in inches ,l ,number of sheets in ream ,s ,weight of paper per ream ,r ,the general formula for the output of paper per hour is #gbj ,f ,d ,r ,output in lbs4 per hour -----------------------4 ,s ,l ,w ,when the number of sheets in the ream is #dhj1 this formula simplifies to #a ,r ,f ,d ,output in lbs4 per hour --------------------4 ,l ,w ,the term nett deckle width applies to the width of the trimmed finished paper at the end of the machine4 ,the formula takes no account of the allowance required for trimming edges4 ,in most cases the deckle width of the machine is arranged so that the paper is cut into strips of equal width when leaving the calenders1 e4g41 a deckle of #hj inches will give #d sheets1 each #bj inches wide4 ,illustration3 ,,fig4 #ci4--,paper ,machine showing ,wire1 ,press ,rolls1 and ,drying ,cylinders4 ,the method by which the general formula is obtained may be explained by an example4 ,what is the output of a machine having a speed of #ajj feet per minute1 with an #hj-;inch deckle1 producing a sheet of paper #bj inches by #cj inches1 weighing #cj lbs4 per ream of #dhj sheets8 ,the machine produces every minute a sheet of paper #ajj feet long and #hj inches wide4 ,hence output per minute in square inches #ab #ajj #hj4 ,output per hour in square inches #fj #ab #ajj #hj4 ,now each 7#bj #cj #dhj7 square inches is area of one ream4 ,output of paper per hour in reams #fj #ab #ajj #hj ------------------4 #dhj #cj #bj ,output of paper per hour in lbs4 #gbj #ajj #hj #cj ------------------- #dhj #cj #bj #fjj lbs4 ,the general formula may be applied for the purpose of calculating the speed at which the machine must be driven4 ,example4--,a machine with #ge-;inch deckle is required to produce #f cwts4 per hour of a paper #be inches by #ah inches 7#ejj sheets71 weighing #ai lbs4 to the ream4 ,at what speed is the machine to be driven8 ,output in lbs4 per hour #gbj ,f ,d ,r --------------------- ,s ,l ,w #gbj ,f #ge #ai #fgb ----------------- #ejj #ah #be ,f #adh feet per minute4 ,,chapter ,,vi ,,brown ,,papers ,,and ,,boards ,common ,browns4--,the raw material used in the manufacture of common brown papers is chiefly jute and waste fibres of every description1 such as waste cuttings from boxboard factories1 old papers1 wood pulp refuse1 and other substances of a like nature4 ,the jute1 in the form of sacking or old gunny bags1 and the hemp refuse1 in the shape of old rope and string1 are subjected to a slight chemical treatment just sufficient to isolate the fibres to a condition in which it is possible to work them up into paper4 ,the bagging and string are cut up in a rag chopper and boiled in revolving boilers with lime or caustic soda for several hours at a pressure of #bj-cj lbs41 the lime being used when it is desired to manufacture a harsh paper1 and the caustic soda being employed for the production of paper having a softer feel4 ,the pulp is not always washed very completely after the process of digestion1 as is the case with white papers1 and it is often possible to extract from brown papers of this class a considerable proportion of the alkaline matter which has not been thoroughly removed from the boiled pulp4 ,the presence of this alkaline residue does not affect the quality of ordinary brown paper1 but is frequently a serious defect in the case of middles or straw boards1 which are afterwards utilised for boxes and covered with coloured papers4 ,the colour of the paper pasted on to such incompletely washed boards is frequently spoilt by the action of the alkali when moistened with the paste used1 many aniline dyes being susceptible to the small proportion of alkali present4 ,the stronger materials1 such as jute or old rope and string1 are either used by themselves or blended with inferior raw material according to the quality of the paper being made4 ,the jute and hemp fibres are generally beaten by themselves in the engine before the other materials are added4 ,the pulp is mixed with the required amount of loading1 while the sizing and colouring operations are carried out in the usual way4 ,the common brown papers are known by a variety of trade names which at one time indicated the nature of the fibrous constituent1 but at the present day the name is no guide or indication of the material used for the manufacture of the paper4 ,the common heavy brown used for wrapping sugar and sundry groceries made in heavy grey and blue shades is a coarse paper made from cheap materials and containing a large proportion of mineral matter4 ,it is usually supplied under the trade name of royal4 ,a somewhat lighter and stronger wrapping paper of a white or buff colour1 used for wrapping groceries1 tea1 and cotton goods1 is that known as casings1 a name probably derived from the application of this paper originally to the lining of cases4 ,manila papers so called were originally made from rope1 but the term is now applied to papers which may be made entirely of wood pulp4 ,rope browns are common papers made of fairly strong material of a miscellaneous character1 this name having been derived from the fact that rope and similar fibre were at one time used exclusively4 ,wood ,pulp ,wrappers4--,most of the papers of the present day are made from wood pulp1 this material giving a thin1 light1 tough paper1 which is pleasant to handle and forms a great contrast to the dense1 opaque1 heavily loaded1 and inartistic specimens produced some years ago4 ,paper of this kind1 though apparently more expensive than common browns1 is really more economical in use4 ,the paper is not only stronger1 but it is possible to obtain a larger number of sheets for a given weight4 ,the great advantage in the improvement of brown papers dates from the introduction of the now well-known kraft papers1 which are of comparatively recent origin4 ,kraft ,paper4--,the term ,kraft1 meaning strength1 is applied to a remarkably strong cellulose paper prepared from spruce and other coniferous woods by the soda treatment1 the special feature of the process being an incomplete digestion of the wood4 ,the wood previously chipped into pieces #a inch to #a inches in length1 is boiled with caustic soda1 the digestion being stopped before the wood pulp has been quite softened1 and while the pulp is still too hard to be broken up into isolated fibres by simple agitation in water4 ,the pulp after thorough washing is disintegrated by means of an edge-runner1 or some form of breaking engine1 the first mentioned probably giving the most satisfactory results1 and converted into paper by the usual methods4 ,the wood can also be reduced by the sulphate process1 in which case the chipped wood is boiled in a liquor to which about #be per cent4 of spent lye from a previous cooking is added4 ,the best results are obtained by attention to the cooking process to ensure an under-cooked pulp1 by careful isolation of the fibres in a kollergang1 or edge-runner1 which machine is capable of separating the fibres without shortening them1 and by proper manipulation on the paper machine4 ,the paper produced under favourable conditions in this direction is wonderfully tough and strong and may be quoted as the most recent example of the fact that the latent possibilities of wood pulp have by no means been exhausted or even thoroughly investigated4 ,imitation ,kraft ,paper4--,if wood is boiled in water at high temperatures the fibre is softened and much of the resinous matter is removed4 ,such wood1 if ground in the same way and by the same methods as ordinary mechanical wood pulp1 is readily disintegrated1 and a long-fibred pulp may be obtained4 ,the process of boiling short #b feet logs of wood in a digester under a pressure of #bj-ej lbs4 has long been known4 ,the wood after boiling is partly washed and then worked up into pulp by the usual mechanical process4 ,the wood is easily ground and yields pulp containing long fibres which in their physical properties closely resemble those of pure wood cellulose1 but the original constituents of the wood are present almost unchanged1 just as in mechanical pulp4 ,the product obtained by grinding is a very tough flexible material of a brownish yellow colour1 and the paper is known as ,nature brown4 ,it is chiefly used for the preparation of tough packing papers1 for the covers of cheap pocket-books1 and other miscellaneous purposes4 ,when this brown mechanical wood pulp paper is glazed on both sides it is then known as ochre glazed1 the word ochre referring to the colour4 ,when made up into light weight papers it is sold as imitation kraft paper4 ,a great variety of wrapping papers are now made from wood pulp1 such as sealings1 sulphite browns1 manilas1 sulphite caps1 but the distinctions between these papers relate chiefly to the amount of finish1 the colour and size of the sheet4 ,the methods of manufacture only differ in small details as indicated by these distinctions4 ,fine ,wrappings4--,the papers used for packing small goods such as silver ware and other delicate articles are generally tissues1 the better qualities of which are made from rag1 and the cheaper qualities from wood pulp4 ,these papers are known as tissue1 crpe1 crinkled tissue1 manila tissue1 and by a variety of trade terms4 ,illustration3 ,,fig4 #dj4--,single ,cylinder or ,yankee ,machine4 ,many of the fine wrappings of the tissue class and the somewhat heavier papers known as ,m4 ,g4 ,caps are manufactured on the single cylinder machine1 which produces a paper having a highly polished surface on one side and a rough unglazed surface on the other side4 ,in the single cylinder machine the beaten pulp passes from the stuff-chest on to the wire of the ordinary ,fourdrinier machine and through the press rolls1 but instead of being dried over a number of cylinders the paper is led over one single cylinder of very large diameter which is heated internally with steam4 ,the paper is usually pressed against the surface of the cylinder by means of a heavy felt1 which is1 however1 sometimes omitted4 ,the side of the paper coming into contact with the cylinder becomes highly polished1 the surface in contact with the felt remaining in an unfinished rough condition4 ,this paper is said to be machine glazed and is known as an ,m4 ,g4 paper4 ,illustration3 ,,fig4 #da4--,section of ,wet ,press1 or ,board ,machine4 ,boards4--,cards1 millboards1 middles1 boxboards1 carriage panels1 and similar paper products are manufactured either on a single board machine1 by means of which single sheets of any required thickness can be obtained1 or on a continuous board machine1 which is capable of producing cards and plain or duplex boards of moderate thickness4 ,the raw material used consists1 as in the case of browns and wrappers1 of every conceivable fibrous substance mixed with mineral matter and then suitably coloured4 ,the preliminary processes for the treatment of the pulp are exactly the same as those employed in the case of brown papers up to the point at which the beating has been effected4 ,,single ,,board ,,machine4 ,the beaten pulp1 diluted with large quantities of water1 is pumped continuously into a large wooden vat of rectangular shape4 ,inside this vat revolves slowly a hollow cylindrical drum1 the circumference of which is covered with wire gauze of fine mesh4 ,the drum is not completely immersed in the mixture of pulp and water1 so that as it revolves the water passes through the wire1 while the pulp adheres to the surface4 ,the water flows regularly into the interior of the drum and runs away through pipes fitted at each side of the vat near the axis of the drum1 and the pulp is brought up out of the water until it comes into contact with a travelling felt4 ,the thin moist sheet of pulp adheres to this felt1 passes through squeezing rolls which remove part of the water1 and is finally carried between two wooden or iron rollers of large diameter4 ,the pulp adheres to1 and is wound up on the upper roller1 the felt being carried back by the lower roller to the vat4 ,when the sheet on the upper roller has attained the desired thickness1 it is immediately cut off and transferred to a pile of similar sheets1 a piece of coarse sacking or canvas being interposed between every wet board4 ,the dimensions of the full-sized board are determined by the diameter of the upper roller and its length4 ,a roll #gd inches wide and #ad inches diameter will give a board #gd inches by #dd inches4 ,as soon as a sufficient number of wet boards has been obtained they are submitted to pressure in order to remove the excess of water and at the same time compress the material into dense heavy boards4 ,the pieces of sacking are then taken out and the boards dried by exposure to air at the ordinary temperature or in a heated chamber4 ,illustration3 ,,fig4 #db4--;,double ,cylinder ,board ,machine4 ,the dried boards are finished off by glazing rolls4 ,these rolls compress the boards still further and impart a polished surface4 ,the amount of finish may be varied by the pressure1 number of rollings1 temperature of the rolls1 and by damping the surface of the dry boards just before they are glazed4 ,the boards are cut to standard sizes before or after glazing4 ,duplex ,boards4--,if the single board machine is fitted with two vats instead of one1 it is possible to manufacture a board with different coloured surfaces4 ,a board coloured red on one side and white on the other is manufactured by having one vat full of pulp coloured red and the second vat full of white pulp4 ,the thin moist sheets from the two vats are brought together and passed through the glazing rolls1 which cause the moist sheets to adhere closely to one another1 the double sheet of pulp so formed being wound up on the rollers at the end of the machine4 ,the board is then dried1 glazed1 and finished in the usual way4 ,the same principle is occasionally adopted on the ,fourdrinier machine for duplex wrappers4 ,thus a common brown pulp is worked up in conjunction with a dyed pulp to produce a brown paper having one surface of good paper suitably coloured4 ,the brown pulp flows on to the wire of the paper machine1 and after it has been deprived of part of the water at the suction boxes1 a thin stream of coloured pulp1 diluted to a proper consistency1 flows from a shallow trough1 placed across and above the wire1 on to the wet brown web of paper in such a manner as to completely cover it as a thin even sheet of coloured pulp4 ,the adhesion of the latter to the surface of the brown paper is practically perfect1 and the weight of the couch and press rolls ensures uniform felting of the fibres4 ,middles4--,this term is applied to a thin or thick cardboard made of common material1 the colour and appearance of which is of little importance for inferior goods4 ,boards of this kind are covered subsequently with papers of all colours and qualities1 and the origin of the word middle is easily seen4 ,the manufacture of a board consisting of two outside papers of good material and a middle produced from common stuff is effected by the continuous boxboard machine1 unless the board is too thick to be passed over drying cylinders1 calendered1 and reeled1 in which case the boards are produced on an ordinary wet machine and the paper pasted on the surface of the dry board4 ,the term is1 however1 now also applied to a common paper made of mechanical wood pulp with perhaps a little chemical pulp1 used for tram tickets1 cheap advertising circulars1 common calendar cards1 and similar purposes1 to which no outer surface of a special character is added4 ,,continuous ,,board ,,machine4 ,this machine differs from the single board machine in that the finished board can be produced from the pulp at one operation4 ,it is used principally for cards and boards of moderate thickness which can be wound up in the form of a reel at the end of the machine4 ,the mixture of pulp and water is pumped into two or more vats and formed into a number of thin sheets1 which are all brought together between squeezing rolls and passed through heavy press rolls which compress the several layers into a compact mass4 ,the thick sheet obtained is dried over steam-heated cylinders which are placed at the end of the press rolls1 and calendered4 ,the whole process1 indeed1 resembles that of ordinary paper-making1 the main difference being the method of producing the wet sheet or card4 ,some machines are constructed with six or seven vats and forty to fifty drying cylinders1 and are capable of turning out a large quantity of finished material4 ,the board can be made of uniform quality and texture throughout1 or be finished off with high-grade paper on one or both sides4 ,in the latter case the constituents of the middle part are waste papers and raw material of inferior quality1 the outer surface of wood pulp1 white or coloured according to circumstances4 ,the variety of papers and boards which can be produced is due to the fact that the several vats of pulp are independent of one another and can be filled with any kind of paper stock4 ,the combined sheets forming the ultimate board are dried on the ordinary cylinders1 calendered1 and reeled up at the end of the machine4 ,,chapter ,,vii ,,special ,,kinds ,,of ,,paper ,there are many varieties of paper products obtained by submitting finished paper to a number of special processes4 ,of these only a few of the more important will be described4 ,these products can be divided approximately into three classes3-- 7#a7 ,papers coated on one side or both sides with various substances1 such as art1 photographic papers1 etc4 7#b7 ,papers impregnated with chemicals1 such as blue print1 medicated1 and cheque papers4 7#c7 ,paper pulp converted into modified products by chemical treatment1 such as vulcanised board1 viscoid1 etc4 ,of the first class1 the coated papers used for art and chromo illustrations are the most important4 ,of the second class1 the blue prints and papers impregnated with chemicals1 chiefly employed for the production of engineers' drawings1 may be regarded as typical4 ,in the third class1 vegetable parchment and vulcanised board are the most familiar4 99 99 99 99 99 ,parchment ,paper4--,this is produced by the action of sulphuric acid upon ordinary paper1 the most suitable for this purpose being made from unsized cotton rag1 free from such additions as mechanical wood pulp4 ,the presence of the latter substance should be avoided1 as it is liable to char or burn1 so that in the finished product it shows itself in the form of small holes4 ,the process depends upon the power of sulphuric acid to change the surface of the paper into a gelatinous mass1 which has been shown to consist of a substance called amyloid4 ,the best parchment is made from pure cellulose such as rag or chemical wood pulp4 ,the quality of the parchment depends upon attention to the strength of the acid1 the temperature of the acid bath1 the period of immersion1 the complete removal of the acid1 and the careful drying of the wet parchment4 ,illustration3 ,,fig4 #dc4--;,apparatus for making ,parchment ,paper4 ,the acid is employed at a strength of #aga specific gravity1 being prepared by diluting the commercial concentrated acid in a leaden vessel1 with a sufficient quantity of water4 ,the parchment is generally prepared by passing a continuous sheet of paper through a bath of acid of the proper strength at a speed which ensures the correct period of immersion4 ,as the treated paper leaves the bath it passes through squeezing rolls which remove the excess of acid1 and the paper is then led through a series of tanks containing fresh water1 the last traces of acid being neutralised by small additions of ammonia1 or some alkali1 to the last washing tank4 ,the wet parchment is then passed through suitable rollers and carefully dried over cylinders heated internally by steam4 ,the paper is kept perfectly stretched as it dries1 because it shrinks enormously1 and would otherwise become cockled and uneven4 ,thick sheets of parchment paper are frequently made by passing three sheets of paper through the acid bath and bringing them together between the rollers before washing4 ,the sheets unite when pressed together2 the remainder of the process being the same as that employed for single sheets4 ,the parchment exhibits remarkable differences to the original paper1 the strength being increased three or four times1 the density about #cj per cent41 the latter being shown by the shrinkage1 which amounts to at least #cj per cent4 ,vulcanised ,paper4--,zinc chloride has the property of parchmentising paper in a manner similar to sulphuric acid4 ,the product obtained when this reagent is used is generally termed vulcanised fibre4 ,the paper is passed as a continuous sheet into a bath of strong zinc chloride1 having a density of #afj-agj ,twaddell1 which causes the cellulose to swell up and partly gelatinise4 ,a very large excess of strong zinc chloride is necessary1 and the process is only rendered commercially possible by careful recovery of the zinc from the washing waters1 which are submitted to chemical treatment4 ,the vulcanised product is subsequently treated with nitric acid or with a mixture of nitric and sulphuric acids to render them waterproof4 ,dextrin is frequently employed to retard the chemical action to permit of the necessary manipulation of the material before it is finally washed4 ,the complete removal of the excess of zinc and acid is a necessary feature of the whole operation4 ,willesden ,paper4--,when paper is passed through an ammoniacal solution of copper oxide1 a superficial gelatinisation of the surface takes place1 so that the paper when washed and dried is impregnated with copper oxide1 which helps to preserve it1 and it becomes waterproof4 ,such material is well known as ,willesden paper4 ,blue ,print or ,cyanotype ,papers4--,this name is usually given to the process by means of which blue prints of engineers' and architects' plans can be reproduced4 ,it was discovered in #ahdb by ,sir ,john ,herschel4 ,it is a useful method of reproducing drawings1 and incidentally is of great value to the amateur photographer because of the facility with which it can be applied for getting proofs from negatives quickly and easily without special baths and chemicals4 ,the process is based upon the reduction of a ferric salt to the ferrous condition by light1 and the formation of ,prussian blue by the action of potassium ferricyanide4 ,the negative cyanotype gives white lines on a blue ground4 ,various formul are in common use4 ---------------------------------------- ---------------------- -- ,herschel4 ,clark4 ,watt4 ,rockwood4 ---------------------------------------- ---------------------- ,solution #a4 ,potassium ferricyanide #af #bg #dh #aj ,water #ajj #ajj #ajj #ajj ,ammonia -- #bc -- -- ,saturated solution of oxalic acid -- #bj -- -- ---------------------------------------- ---------------------- ,solution #b4 ,ammonia-citrate of iron #bj #cj #ej #cj ,water #ajj #ajj #ajj #ajj ,boric acid -- -- #je -- ,dextrin -- -- -- #e ---------------------------------------- ---------------------- ,equal parts of the two prepared solutions are mixed when required and spread evenly over well-sized paper4 ,the paper is hung up1 dried1 and preserved in a dark dry place4 ,the positive cyanotype gives blue lines on a white ground1 being the reverse of the ordinary blue print4 ,that is1 no image is formed where the light acts1 and the reaction is the formation of blue due to the union of a ferrous salt with ferrocyanide of potassium4 ,pizzighelli in #ahha gave the following formula3-- ---------------------------------------- --------------------------- -- ,solution #a4,solution #b4,solution #c4,solution #d4 ---------------------------------------- --------------------------- ,water #ajj #ajj #ajj #ajj ,gum arabic #bj -- -- -- ,ammonia-citrate of iron -- #ej -- -- ,ferric chloride -- -- #ej -- ,potassium ferrocyanide -- -- -- #bj ---------------------------------------- --------------------------- ,mix the first three solutions in the following order in the proportions stated3-- ,solution #a4 #bj parts4 ,solution #b4 #h ,solution #c4 #e ,as soon as the solution1 which at first gets thick and cloudy1 is clear and thin1 it is spread over the surface of well-sized paper1 which is then dried in a warm room4 ,the print1 which appears yellow on a dark yellow ground1 is treated with the developer 7solution #d7 by means of a brush dipped in the solution4 ,when the image is deep blue in colour1 the print is washed in water and then placed in dilute hydrochloric acid 7#a part of acid to #aj parts of water7 till the ground is quite white4 ,a final washing with water is then necessary4 ,waterhouse gives the following formula3-- ---------------------------------------- ------------------------- -- ,solution #a4,solution #b4,solution #c4,solution #d4 ---------------------------------------- ------------------------- ,water #fej #aej -- #ajj ,gum arabic #agj -- -- -- ,tartaric acid -- #dj -- -- ,ferric chloride solution #de ,baum -- -- #aej -- ,ferrocyanide of -- -- -- #bj potassium ---------------------------------------- ------------------------- ,solutions #a and #b are mixed and ,no4 #c added gradually with constant stirring4 ,the mixture is left twenty-four hours1 and diluted with water to a specific gravity of #aajj4 ,the paper is coated with the solution and used as already directed1 being developed in ferrocyanide of potassium solution and washed with water1 treated with weak hydrochloric acid1 and then finally cleaned from all traces of acid4 ,black ,lines on a ,white ,ground4--,this modification of the ordinary blue print is arrived at with the following formula3-- ,water #ifj parts4 ,gelatine #ae ,perchloride of iron 7in syrupy condition7 #fj ,tartaric acid #fj ,sulphate of iron #ae ,the paper is coated with the solution4 ,after printing1 the image is developed with a solution containing ,gallic acid #a part4 ,alcohol #aj parts4 ,water #ej ,a final washing of the print with water completes the operation4 ,,coated ,,papers4 ,this term should properly include all the varieties of special papers which are coated with extraneous matter for particular purposes1 such as art1 chromo1 tinfoil1 gilt1 emery1 carbon1 photographic1 marble1 and sand papers4 ,in practice however1 the term is almost entirely limited to art papers used for illustration work and half-tone printing4 ,an art paper1 using the definition given above1 consists of an ordinary sheet of paper1 one or both sides of which have been coated by the application of a mixture of a mineral matter1 such as china clay or satin white1 and some adhesive1 like casein or glue4 ,the object of the coating is to impart to the paper a perfectly smooth surface1 rendered necessary because of the conditions under which the printing of the illustrations is carried out4 ,illustration3 ,,fig4 #dd4--;,general arrangement of ,plant for making ,art ,paper4 ,the machine used for coating the paper consists of a large hollow drum about #dj inches diameter and #dh inches wide4 ,the paper is brought over upon the drum in a continuous sheet1 and the coating mixture applied to the surface by means of a revolving brush or an endless felt which rotates in a copper trough containing a coating mixture which is usually maintained at a temperature of #abj ,fahr4 ,the amount of material put on to the surface of the paper is varied by altering the proportion of water in the trough4 ,as the wet coated paper is drawn over the drum it comes into contact with a number of flat brushes which move from side to side and brush the coating well into the paper4 ,illustration3 ,,fig4 #de4--,sectional ,elevation of ,coating ,plant4 ,the last two or three brushes on the drum are made of very fine bristles1 so that when the coated paper leaves the machine the surface is perfectly even and free from brush marks4 ,the wet paper is then drawn up an inclined ladder by an ingenious device1 which causes the paper to fall into festoons or loops1 and these are carried bodily forward by means of travelling chains4 ,the process1 somewhat difficult to describe1 is more easily understood by a study of the illustrations given4 ,the paper is dried by a current of warm air which can be obtained by means of steam pipes placed below the festoons or with a special air blower4 ,the dry paper is then led through guide rolls and wound up in the form of a reel4 ,the paper at this stage has a dull coated surface1 which is somewhat rough and unfinished1 and a high polish is imparted to it by a machine known as a supercalender4 ,the supercalender consists of a number of alternate steel and cotton or paper rolls placed vertically in a stack one above the other4 ,when the coated paper is led through this machine the friction of the alternate steel and cotton rolls produces a high finish on its surface4 ,an art paper coated on both sides is manufactured by passing the paper through the coating machine twice4 ,machines have been devised for coating both sides of the paper at one operation1 but these are not in very general use4 ,tinted art papers are prepared in the same manner1 the desired colour being obtained by the addition of pigments or aniline dyes to the mixture in the trough containing the coating materials4 ,when the two sides of such tinted papers are coloured differently1 they are often described as duplex coated papers4 ,imitation ,art ,papers are prepared by quite a different process1 although they have the appearance1 more or less1 of the coated paper4 ,they are merely esparto papers very heavily loaded1 containing frequently as much as #be to #cj per cent4 of mineral matter prepared as follows3-- ,bleached esparto half-stuff is beaten together with any suitable proportion of chemical wood pulp in an ordinary beating engine1 and a large quantity of china clay is added at the same time4 ,the beating is carried out under conditions which favour the retention of as much china clay as the pulp will hold while being converted into paper on the ,fourdrinier machine4 ,after the paper passes over the drying cylinders of the machine it is passed through the calenders in the usual way1 but the surface of the paper is damped by means of a fine water spray just before it enters the calender rolls4 ,the result is that a water-finish1 so called1 is imparted to the paper1 and a close imitation of the genuine art paper is obtained1 the effect of this peculiar treatment being to compress the fibres and bring the clay up1 as it were1 to the surface4 ,a paper containing such a large proportion of mineral matter intimately mixed with the fibre is naturally very weak4 ,it easily tears1 and if moistened with water goes all to pieces4 ,at the same time it is a cheap substitute for high-class art paper1 being suitable for circulars1 temporary catalogues1 and similar printed matter4 ,in an art paper the nature of the fibrous constituents is too often regarded as a matter of secondary importance1 because in the process of printing the ink does not come into contact at all with the paper1 and an impression is produced merely on a layer of clay which is bound together by the glue4 ,the illustrations are not absolutely permanent1 and it is perfectly easy to remove the whole of the impression and the coating itself by immersing a sheet of the paper in warm water and rubbing the surface gently with the fingers1 or with a camel-hair brush4 ,in fact the amount of coating matter which has been brushed on to a paper can be determined approximately by weighing a piece of the coated paper1 removing the mineral matter and glue from both sides as indicated1 allowing the paper to dry again1 and then re-weighing1 the loss in weight representing the amount of coating4 ,it is not surprising to find that the true paper is merely regarded as a convenient means of producing1 so to speak1 a smooth surface of clay1 and an examination of the material between the two clay surfaces often reveals a paper of very low quality4 ,there are one or two empirical methods for testing the condition of coating on an art paper4 ,if the coating is firm and adherent1 then on pressing the moistened thumb on to the surface none of the coating matter is removed1 but in a badly-made art paper some of the coating adheres to the thumb4 ,another method is to crumple a sheet of paper between the fingers1 and if any of the coating comes away easily the paper is considered of poor quality4 ,the complete examination of an art paper1 apart from the practical test of printing1 involves the determination of the amount of coating matter added to the paper1 the proportion of glue in the coating1 and the usual analysis of the paper itself4 ,,packing ,,papers4 ,this term may be applied to wrappings specially treated with substances which render the paper air and water proof4 ,they are principally used for preserving food1 or such articles as tobacco1 which require to be kept slightly moist4 ,waxed ,paper4--,the paper in the form of a continuous sheet is passed through a bath of melted wax at a high temperature1 any excess being removed by squeezing rolls through which the hot waxed paper is passed4 ,the paper is led over skeleton drums and thoroughly cooled before being cut into sheets4 ,butter ,paper4--,ordinary parchment paper is generally used1 but for special purposes a solution containing albumen and saltpetre is utilised for impregnating paper4 ,hardware ,paper4--,needles and silver goods are frequently wrapped in paper impregnated or mixed with substances which are supposed to prevent deleterious fumes from coming into contact with them4 ,the use of black papers heavily loaded with pigment1 sized with glue and an excess of alum1 is commonly resorted to4 ,for silver ware1 paper dipped in a solution of caustic soda containing zinc oxide is used4 ,a recent patent suggests the impregnation of paper with heavy hydrocarbon oils1 which being slightly volatile cover the goods1 such as needles1 with a thin film4 ,paraffin ,paper4--,large quantities of this paper are consumed for packing food and other articles which need protection from air and moisture4 ,the paper is either passed through a bath of paraffin or passed over a roller which rotates in a trough of paraffin4 ,if the paper is to be coated on both sides it is passed through the bath containing the paraffin in a melted condition1 the excess of which is scraped from the paper as it leaves the bath4 ,the paper is cooled by exposure to air1 and when the paraffin has solidified upon the sheet the paper is wound up on a roller at the end of the machine4 ,if the paper is to be coated on one side only it is passed over a heated roller which revolves in a bath of melted paraffin1 the other operations of drying and finishing being the same as in the case of a paper coated on both sides4 ,tinfoil ,papers1 required for packing tea1 coffee1 and similar foodstuffs1 are prepared by coating cheap paper with a solution of gum and finely powdered tin4 ,the manufacture of the fine powder is accomplished by melting tin at a low temperature and shaking it continually as it cools down1 whereby a mixture of fine powder and large particles is produced1 the latter being separated out by agitation of water4 ,tin in a fine state of division can also be obtained by a chemical process4 ,granulated tin is dissolved in strong hydrochloric acid1 the solution diluted with water1 and a stick of zinc introduced into the solution4 ,the tin is gradually precipitated4 ,the dried powder is coated on to the paper with gum1 and when the paper is dry the necessary degree of brilliancy produced by suitable calendering4 ,transfer ,papers4--,a number of important operations require the use of what are known as transfer papers1 so that a design written or printed upon a specially prepared surface can be transferred to another surface from which duplicate copies may be obtained4 ,the principle upon which all such operations are based is the coating of suitable paper with starch1 flour1 and gum1 singly or mixed1 so as to give a surface firm enough to take the design1 but which readily breaks up when the printed side is pressed against the wood1 stone1 or metal object intended to receive the design4 ,thus a paper may first be dusted over with dry starch1 or coated with starch paste and then dried4 ,a layer of dextrine may then be put over the starch coating1 and the design printed upon the dextrine surface4 ,when the paper is turned face downward on a sticky metal plate the design adheres to the metal1 and the paper is easily pulled off1 owing to the dry starch layer between it and the dextrine being non-adhesive4 ,this principle is utilised in producing designs upon tins used for packing1 metal advertisement plates1 domestic articles of every kind1 stoneware and earthenware goods4 ,it is further applied in the preparation of lithographic stones required for printing4 ,each class of work demands paper of a suitable character1 but the principle of an easily detached surface-coating is the same for all4 ,the main difficulty experienced is the liability of paper to stretch when damped1 and various methods are devised to obviate this1 either by employing paper which stretches very little when damp1 or by making the paper partially waterproof before use4 ,papier-mch4--,this name indicates a preparation of paper or paper pulp mixed with various mineral substances firmly cemented together by animal or vegetable adhesives4 ,the paper pulp used for high-class goods consists of pure wood cellulose1 while for the commoner qualities mechanical wood pulp1 waste papers1 and any similar fibrous material are employed4 ,the mineral substances used are china clay1 chalk1 gypsum1 barytes1 ochre1 sienna1 and other mineral pigments4 ,the adhesive materials are glue1 casein1 gum1 starch1 paste1 dextrine1 ,iceland moss1 or wax4 ,for experimental purposes1 small quantities of papier-mch may be prepared in the following manner3-- ,when old newspapers or brown papers are used as the fibrous basis of the papier-mch1 they are first torn up into small pieces1 moistened with hot water1 tied up in a small cloth bag or sack1 which must only be half filled1 and then immersed in a basin of warm water and thoroughly kneaded by hand1 so that the paper is gradually reduced to the condition of pulp4 ,if the kneading process is carried out thoroughly the paper is entirely reduced to pulp4 ,the excess of water can be removed by pressure and the preparation of the final mixture completed by the incorporation of clay1 pigment1 and adhesive4 ,in the preparation of papier-mch for goods on a large scale a beating engine is used in order to break up the old paper or wood pulp into a fibrous condition4 ,the following formul can be used for making papier-mch3-- ---------------------------------------- -------- 7#a7 7#b7 7#c7 7#d7 ---------------------------------------- -------- ,pulp #bb ,pulp #bb ,pulp #ab ,pulp #cc ,clay #cg ,chalk #cj ,rosin size #bb ,starch #i ,casein #cg ,glue #d ,flour #aa ,clay #i ,water #d ,water #dd ,china clay #aa ,water #di ,water #dd --- --- --- --- #ajj #ajj #ajj #ajj ---------------------------------------- -------- ,plaster ,moulds4--,plaster of ,paris or gypsum is the main article used for moulds and pattern4 ,the preparation of gypsum for casting is made as follows3--,the gypsum is gradually worked up into a creamy paste with water1 the mixing being done quickly yet thoroughly4 ,the pattern of which it is desired to form a mould must be coated with oil4 ,around the pattern placed on a table a wall of wood or pasteboard is fixed1 so that a basin will be formed of suitable depth1 preventing the gypsum from flowing away4 ,patterns of figures or of curved articles have to be made in two or more parts4 ,for that purpose the pattern is usually cut into two pieces4 ,two moulds are now readily obtainable by first oiling the pattern and by pouring the gypsum in a thin state gradually over the surface1 to avoid the forming of air bubbles4 ,the rapid drying of the soaked gypsum is sometimes inconvenient1 but the addition of a saturated solution of borax in water to the gypsum mixture can be resorted to as a check4 ,various means are employed for hardening and strengthening the plaster cast1 such as the addition of coarse paper fibres1 shreds of canvas1 iron filings1 or wire4 ,colouring4--,usually a cheap water colour only is required2 a light coating of a cheap varnish may be sufficient4 ,in other cases a water colour serving as a filler for smoothing the surface may receive a finish of one or more coats of resinous solutions in alcohol or of copal varnish4 ,many goods are coated with asphaltum or ,japan varnish and dried in cold or hot air4 ,some of the articles may be decorated with scrolls or arabesques in oil colours or enamels1 or the lines may be covered with bronze powder1 or with metal1 gold1 or aluminium leaf4 ,varnishing4--,the following varnish recipes are suitable3-- ---------------------------------------- ---------------- 7#a7 7#b7 7#c7 7#d7 ---------------------------------------- ---------------- ,shellac #bj ,shellac #aj ,shellac #f ,sandarac #ae ,alcohol #gj ,rosin #aj ,sandarac #c ,mastic #e ,lamp black #aj ,alcohol #fj ,mastic #ah ,turpentine #e ,lamp black #bj ,alcohol #gc ,alcohol #ge --- --- --- --- #ajj #ajj #ajj #ajj ---------------------------------------- ---------------- ,,chapter ,,viii ,,chemicals ,,used ,,in ,,paper-,,making ,the manufacture of paper is a highly technical industry1 which requires a practical knowledge of mechanical engineering1 as well as an intimate acquaintance with the many important chemical problems connected with the art4 ,the following brief description of the various chemicals used in the manufacture of paper is divided into certain classes1 based upon the order of the operations through which the raw material passes before its final conversion into paper3-- 7#a7 ,the alkaline processes used for treating raw fibre3 soda ash2 caustic soda2 lime2 recovered ash4 7#b7 ,the conversion of wood into sulphite pulp3 sulphur2 limestone4 7#c7 ,the operation of bleaching3 bleaching powder2 antichlors2 acids4 7#d7 ,the sizing and loading of paper3 casein2 gelatine2 rosin size2 alum2 starch2 silicate of soda2 pigments and soluble dyes2 mordants4 ,mineral substances for loading3 clay1 blanc fixe1 etc4 ,carbonate of ,soda4--,this substance1 also known under the trade names of alkali and soda ash1 is used in the paper mill for the manufacture of caustic soda4 ,it is purchased by the paper-maker from the chemical works1 and used together with the recovered ash 7see page #gh7 for the production of caustic soda solution1 which is required in the treatment of raw fibres4 ,it is also used for the preparation of rosin size 7see ,rosin ,size7 and in softening hard waters for steam-raising purposes4 ,,sodium ,,carbonate ,,table4 ,showing percentage by weight and pounds per #ajj gallons in solutions of various densities4 ---------------------------------------- --------------------------- ,percentage by ,weight4 #ajj gallons contain pounds of ,twaddell4------------------------------ -------------------------- ,na#b,o4,na#b;,,co#c4 ,na#b,o4,na#b;,,co#c4 #dh per cent4 ,ash4 ---------------------------------------- ------------------------ #a #jbh #jdg #bgf #dgb #egd #b #jef #jie #efa #ifj #aafh #c #jhd #adb #hdb #adda #agef #d #aaa #aij #aacd #aich #bcfd #e #aci #bch #adbf #bddj #bigc #f #afg #bhe #agaj #bicf #cegg #g #aie #ccc #bjaf #cddf #dbjj #h #bbb #chj #bcab #cieb #dhae #i #bej #dbh #bfag #ddgb #edej #aj #bgh #dgf #biga #ejjj #fjij #aa #cjf #ebc #cbbg #eeah #fgbb #ab #ccd #ega #cecf #fjej #gcgb #ac #cfa #fag #chdc #fegb #hjjg #ad #chh #ffd #daeg #gajf #hfeh #ae #daf #gaj #ddfe #gfcc #icjc #af #ddb #geg #dghj #hagg #iifa #ag #dgj #hjd #eajb #hgbd #ajfca #ah #dig #hea #edbe #ibgd #aacaj #ai #ebd #hig #egde #ihbf #aaigj #bj #eeb #idc #fjfg #ajcgj #abfdb #ba #egi #iij #fcih #ajidj #accde #bb #fjf #ajcg #fgcb #aaeaj #adjab #bc #fcc #ajhc #gjfc #abjha #adgaj #bd #ffa #aacj #gdjj #abffb #aedbj #be #fhh #aagf #ggch #acbcj #afaab #bf #gae #abbc #hjhc #achbj #afhea #bg #gdb #abgj #hdca #addab #agegj #bh #ggj #acaf #hgfg #aejbj #ahbgj #bi #gig #acfc #iabh #aefae #aijad #cj #hbd #adji #idgg #afbjj #aigdj ---------------------------------------- ------------------------ ,analysis4--,the value of soda ash1 carbonate of soda1 and recovered ash depends on the amount of available alkali 7,na#b,o7 present4 ,a weighed quantity 7#aee grammes conveniently7 is dissolved in a measured volume of distilled water 7#ejj c4c471 and titrated with standard normal hydrochloric acid1 methyl orange indicator being used4 ,caustic ,soda4--,raw vegetable fibres may be reduced to the condition of paper pulp by treatment with caustic soda4 ,in practice this process is largely resorted to for the manufacture of pulp from esparto1 straw1 and wood1 the spent caustic soda being recovered and used again4 ,the paper-maker prepares the caustic required for digesting the raw material from recovered ash and carbonate of soda4 ,a convenient volume of clear liquor obtained by lixiviating the recovered ash is boiled with lime in suitable causticising pans1 the reaction being represented as follows3-- ,na#b;,,co#c ,ca,o ,h#b,o #b ,na,o,h ,ca,c,o#c4 ,soda ash ,lime ,water ,caustic soda ,chalk4 ,according to this equation1 #ajj lbs4 of soda ash require #ec lbs4 of quicklime1 but a slight excess is generally added1 #eh or #fj lbs4 being the usual amount actually employed4 ,several precautions should be observed in the process of causticising4 7#a7 ,the liquor from the recovered soda should be bright and clear1 indicating complete incineration of the ash4 7#b7 ,the liquor is best causticised at a density between #ajej and #aajj 7#aj-bj1 ,twaddell74 ,with stronger solutions the reaction is complicated and the yield of caustic soda reduced4 ,lunge has shown that if the density of the solution is #ajbe the proportion of soda causticised is #iie per cent41 whereas at a density of #aaej it is only #ide per cent4 ,in the latter case the caustic soda formed acts upon the chalk produced and is reconverted into carbonate4 7#c7 ,the large quantities of chalk residue resulting from the reaction must be thoroughly and carefully washed4 ,the economy of the whole process depends in no small measure upon this seemingly small detail4 ,,caustic ,,soda ,,tables4 ,showing quantity of liquor obtained from #a cwt4 of caustic soda and the amount of caustic soda in #ajj gallons of liquor 7adapted from ,lunge and others74 ---------------------------------------- ----------------------------- ,gallons obtained per ,pounds of ,caustic ,soda hundredweight per #ajj gallons ,liquor4 of ,caustic4 ,twaddell4-------------------------,twad dell4------------------------ #fj per cent4#gg per cent4 #fj per cent4#gg per cent4 ,caustic4 ,caustic ,caustic4 ,caustic ,pure4 ,pure4 ---------------------------------------- --------------------------- #a #a1ggg #b1ceh #a #fc #dge #b #hif #a1agi #b #abe #ie #c #eif #gfg #c #ahh #adf #d #ddh #egd #d #bej #aie #e #cei #deg #e #cab #bde #f #bih #chd #f #cgf #bib #g #bef #ccj #g #dch #cdj #h #bbc #bhg #h #eja #cij #i #aii #bef #i #efb #dcg #aj #agh #bbi #aj #fbi #dhi #aa #afb #bjh #aa #fia #ecg #ab #adh #aij #ab #geg #ehg #ac #acf #agf #ac #hba #fcg #ad #abf #aff #ad #hhe #fge #ae #aage #aeb #ae #iej #gce #af #aaj #adae #af #ajae #gij #ag #ajce #ace #ag #ajgh #hcj #ah #ih #abee #ah #aadd #hij #ai #ibh #aaie #ai #abjh #ich #bj #hh #aad #bj #abgb #ihj #be #gj #ijc #be #aeie #abdj #cj #efe #gc #cj #aigc #aecj #ce #dh #fae #ce #bcdi #ahbb #dj #da #ec #dj #bgbf #baaf #de #cec #dee #de #cagd #bdfc #ej #ca #dj #ej #cfba #bhaj ---------------------------------------- --------------------------- ,,dilution ,,table ,,for ,,strong ,,liquors4 ,showing number of gallons of water required to reduce the density of #ajj gallons of liquor from a higher density1 ,d1 to a lower density1 d4 7,see page #afc74 ---------------------------------------- ---------------------------- ,higher ,lower ,density1 d4 ,density1 ,d ---------------------------------------- ------- 7,twaddell74 #ad4 #ac4 #ab4 #aa4 #aj4 #i4 #h4 #g4 #f4 #e4 #d4 ---------------------------------------- ------------------ #db #bjj #bbc #bej #bhahcbjcfg #dbeejj #fjj #gdjiej #dj #ahe #bjg #bcccbfcfcjjcddddjjdgadefffgjjijj #ch #aga #aib #baffbdeebhjcbbbcgeddbhecccffjhej #cf #aeg #agg #bjj #bbgcbfjcjj #cejdadcejj #fbjhjj #cd #adc #afaeahccbjiabdjbgggcbechegdfffehjgej #cb #abhfadf #afffaia #bbjbeeecjjcegadcccedjgjj #cj #aadcacjfaej #agbhbjjbcccbgecbhedjj #ejjfej #bh #ajj #aaecacccaedfahjbaaabejcjj #cfffdfjfjj #bf #hegajj #aaffacfdafjahhhbbebgadccccdbjeej #bd #gad #hdfajj #aahbadjafffbjjbdc #cjj #chjejj #bb #ega #fib #hccajj #abjadddagebaddbfffcdjdej #bj #dc #ecf #fff #hahajjabbbaejahegbccccjjdjj #ah #bhf #chd #ej #fcg #hjajj #abeaeg #bjj #bfjcej #af #adc #bc #ccc #dee #fj #gggajjabheafffbbjcjj ---------------------------------------- ------------------ ,lime and ,limestone4--,carbonate of soda and recovered ash are converted into caustic soda by means of lime4 ,about sixty parts of lime are necessary for the conversion of #ajj parts of carbonate of soda4 ,large quantities of insoluble carbonate of lime are produced in this operation1 and great care is necessary to prevent a loss of caustic soda which occurs if the residue is not thoroughly washed4 ,in some cases the residual chalk is drained by vacuum filters in order to remove all traces of soluble alkali4 ,processes have been devised for calcining the residue so as to convert the carbonate into caustic lime to be used over again1 but no economical and practical method has yet been found4 ,the treatment of the residual chalk with sulphuric acid for the production of calcium sulphate appears feasible1 but the substance obtained is very impure1 and therefore has little commercial value4 ,limestone is required in considerable quantity for the preparation of sulphite of lime for the manufacture of wood pulp4 ,recovered ,ash4--,the black liquor obtained during the process of the boiling of straw1 esparto1 and other paper-making fibres contains a large proportion of non-fibrous organic constituents derived from the fibres1 the quantity of which may be gauged from the fact that these fibres generally lose #ej per cent4 of their weight when being boiled4 ,the black liquor on evaporation yields a thick resinous mass1 which is converted into carbonate of soda when burnt4 ,advantage is taken of this fact to carry out a process of incineration on a large scale1 so that heat derived from the burning off of the resinous mass is utilised for evaporation of weaker liquors4 ,the ash is drawn from special furnaces1 put aside1 and allowed to char quietly1 so that the carbonaceous matter is more or less completely burnt away4 ,the ash in this form contains about #dj per cent4 of soda1 its composition being determined by the nature of the fibre which has been treated4 ,in the case of straw1 the amount of silicate is considerable1 as shown by the following typical analysis3-- ,sodium carbonate #gjb ,sodium hydrate #bc ,sodium sulphate #da ,sodium chloride #ge ,silica #ge ,oxides of iron and alumina #jge ,unburnt carbon1 etc4 #gfe ------ #ajjjj ------ ,at the present time there is no process in general use for the recovery of the liquors used in the treatment of wood by the sulphite process4 ,many schemes have been proposed1 the most promising of which is that of ,drewsen4 ,sulphur and ,sulphites4--,the pale yellow brittle substance known as sulphur is too familiar to require any detailed description4 ,it unites with oxygen in various proportions1 and these in contact with water form the various sulphur acids known to commerce4 ,sulphur burned with a limited quantity of air forms sulphurous acid gas1 and this substance is the chief product of oxidation1 which by further treatment can be converted into sulphites4 ,in the manufacture of the sulphur compounds required in the preparation of wood pulp1 the furnace for burning the sulphur consists of a flat-bottomed cast iron retort which is very shallow1 and provided with a curved top1 to which a pipe is fixed1 so that the sulphurous acid may be conveyed away from the furnace4 ,in the most recent form of sulphur oven a small conical-shaped revolving furnace is employed1 which produces a satisfactory gas of constant composition very economically4 ,bisulphite of ,lime4--,this compound is obtained when the sulphurous acid gas is brought into contact with moistened limestone4 ,in the manufacture of bisulphite of lime on a large scale the sulphurous acid gas is drawn or pumped up tall circular towers filled with blocks of limestone1 kept moistened by a carefully regulated stream of water flowing from the top of the tower4 ,in another system known as the acid tank process1 the gas is forced into large circular vats containing milk of lime4 ,in either case a solution is prepared containing bisulphite of lime1 together with a certain proportion of free sulphurous acid1 the object of the pulp manufacturer being to obtain a solution containing as large a proportion of free sulphurous acid as possible4 ,the composition of a solution will vary on this account1 and the following may be quoted as being an example of such a liquor3-- ,free sulphurous acid #cbc per cent4 ,combined sulphurous acid #jgg ---- #djj ---- ,for experimental purposes the bisulphite of lime solution may be prepared by passing sulphurous acid gas into a mixture of water and sulphite of lime4 ,the latter compound is insoluble in water1 but gradually dissolves when the gas is absorbed4 ,a known weight of sulphite of lime is added to a measured volume of water1 and the sulphurous acid gas discharged into the mixture from a siphon of compressed sulphurous acid4 ,the amount of gas absorbed is determined by weighing the siphon before and after use1 the loss of weight representing the gas discharged4 ,the following figures may be quoted as an example3-- ,quantities used4 ,calcium sulphite #ecf grammes4 ,water #gajj c4c4 ,gas absorbed #ecd grammes4 ,density of solution #ah ,twaddell4 ,the composition of the solution prepared is-- ,combined sulphurous acid #cej ,free sulphurous acid #fed ,lime #cjf ,water #hfij ------ #ajjjj ------ ,analysis4--,the examination of sulphite liquors for free and combined sulphurous acid is made by means of standard iodine solution and normal caustic soda solution4 ,a known volume of the sulphite liquor is first titrated with standard iodine solution1 the number of cubic centimetres required being a measure of the total sulphurous acid4 ,each cubic centimetre standard iodine solution #jjcb grammes ,,so#b4 ,the titrated liquor is then treated with standard caustic soda in quantity sufficient to exactly neutralise the acid4 ,the volume of caustic soda solution used minus the number of cubic centimetres of iodine first added is a measure of the free sulphurous acid4 ,bleaching ,powder4--,this substance is prepared on a large scale by allowing chlorine gas to act upon dry slaked lime4 ,the lime absorbs nearly one-half its weight of chlorine and forms a dry white powder1 having a very pungent odour4 ,the best bleaching powder contains about #cg per cent4 of what is termed available chlorine4 ,the substance1 on being treated with water1 gives a greenish-coloured solution known as bleach liquor1 and when raw paper-making material1 after having been digested with caustic soda1 is treated with this solution1 it is gradually bleached to a white colour4 ,the composition of the powder may be represented approximately as follows3-- ,available chlorine 7combined with lime7 #cfjj ,chlorine in the form of chloride #jcb ,chlorine in the form of chlorate #jbf ,lime #ddff ,magnesia #jdc ,silica1 iron oxides1 etc4 #acc ,insoluble matter #agjj ------ #ajjjj ------ ,since the amount of bleach used for wood pulps varies from #h per cent4 to #be per cent4 of powder on the dry wood pulp1 the cost of bleaching in some cases is considerable4 ,the economy of the process depends in some measure upon the care exercised in the purchase of bleaching powder of standard quality1 the storage of same in a dark1 cool place1 and the efficient treatment or exhaustion of the powder when the bleach liquor is prepared4 ,the powder is usually agitated for about an hour with water sufficient to produce a liquor of #ac-ae ,twaddell4 ,the undissolved powder is allowed to settle and the clear solution siphoned off1 after which the sediment is washed once or twice to remove all the soluble matter completely4 ,,bleach ,,liquor ,,table4 ,showing for bleaching powder solutions of known density the quantity of powder necessary to produce #ajj gallons of liquor and the number of gallons obtained from #a cwt4 of powder 7adapted from ,lunge and ,beichofen74 ---------------------------------------- ------------------------------ ,available ,number of ,gallons obtained,pounds of ,powder per #ajj ,chlorine from #aab lbs4 of ,powder4 gallons of ,liquor4 ,twaddell4,pounds ---------------------------------------- --------- per #ajj #cd per cent4#ce per cent4 #cd per cent4#ce per cent4 gallons4 ,powder4 ,powder4 ,powder4 ,powder4 ---------------------------------------- ---------------------------- #jbe #jgj #e1dfd #e1fjj #bje #bjj #jej #adj #b1gbe #b1hjj #daa #djj #a #bga #a1dje #a1dde #gig #ggd #b #eeh #fha #gjb #afda #aeid #c #hdh #ddh #dfb #bdie #bdbc #d #aada #ccd #cdj #ccee #cbfj #e #addg #bfd #bgj #dbeh #dacd #f #agcf #baie #bbe #eajf #difj #g #bjdd #ahf #aia #fjaa #ehdj #h #bcge #afj #afe #fihe #fghe #i #bffb #ada #adg #ghcj #gfeg #aj #bifj #abi #acbe #hgjf #hded #aa #cbfh #aafe #abj #ifaa #iccg #ab #ceha #ajfe #ajie #ajecb #ajbca #ac #ciaj #ih #ajj #aaejj #aaagj #ad #dbca #ij #ibe #abdde #abjij #ae #degj #hd #hf #acdda #acjef #af #dhif #gh #hj #adchj #aciga #ag #ebbg #gce #ge #aecec #adicd #ah #eeah #fi #ga #afbcj #aegfe #ai #ehdj #fee #fg #agajj #affhf #bj #faej #fae #fd #ahjhh #agega ---------------------------------------- ---------------------------- ,the best method for extracting powder is to agitate the material with water for a short period1 and to stop the mixing process directly the maximum density has been obtained1 which usually takes place in #ae minutes4 ,prolonged agitating prevents the powder from settling readily4 ,the maximum quantities of liquor which can be obtained from bleaching powder are shown on page #afb4 ,the following table is useful as showing the amount of water required for diluting strong liquors1 the figures being applicable to any solution independent of the nature of the dissolved substance4 ,,dilution ,,table ,,for ,,weak ,,liquors4 ,showing number of gallons of water required to reduce the density of #ajj gallons of liquor from a higher density1 ,d1 to a lower density1 d4 7,see page #aeg47 ---------------------------------------- ------------------------------- ,higher ,lower ,density1 d4 ,density1 ,d ---------------------------------------- --------- 7,twaddell74 #ab4 #aa4aj4 #i4 #h4 #g4 #f4 #e4 #d4 #c4 #b4 #a4 ---------------------------------------- -------------------- #af #cccded #fjgggajj #abheafffbbjcjjdcccgjja1ejj #ae #bejcfd #ejfff #hgeaadcaej #bjjbgedjj #feja1djj #ad #affbgc #djeee #ge #ajj #acccahjbejcffffjja1cjj #ac #hcahb #cjddd #fbe #hegaaffafjbbecccceeja1bjj #ab #ia #bjccc #ej #gadajj #adjbjjcjj #ejja1ajj #aa #ajbbb #cge #ega #hccabjagebfffdeja1jjj #aj #aaa #be #dbh #fffajjaejbcccdjj #ijj #i #abe #bhe #ej #hjabebjj #cej #hjj #h #adb #ccc #fjajjafffcjj #gjj #g #aff #dj #geacccbej #fjj #f #bj #ejajj #bjj #ejj #e #be #fffaej #djj #d #cccajj #cjj ---------------------------------------- -------------------- ,antichlors4--,the residues of chlorine which may be left in pulp after bleaching are frequently neutralised by the use of substances termed antichlors1 which react with the calcium hypochlorite1 converting it into chlorides4 ,the sodium hyposulphite is the most frequently used antichlor1 the reaction between this and hypochlorite resulting in the formation of calcium sulphate and sodium chloride2 #ajj lbs4 of commercial bleaching powder will require #cj lbs4 of crystallised sodium hyposulphite4 ,the sulphites of soda and lime also act as antichlors1 reducing the hypochlorite of calcium into sulphate of lime or soda4 ,the chief advantage of the use of sulphites is to be found in the fact that the substances obtained by the reaction are neutral4 ,the best practice in bleaching is to avoid the necessity for using any forms of antichlors by careful regulation of the bleaching process4 ,it has already been suggested in previous references to bleaching that the desired results are obtained when the pulp and bleach are left in contact with one another in tanks or drainers until the bleach is completely exhausted1 the residual salts in solution being removed by thorough washing4 ,gelatine4--,for animal-sized or tub-sized papers gelatine is used4 ,it can be prepared by the paper-maker from hide clippings1 sheep skins1 bone1 etc41 or can be purchased ready made4 ,beadle gives the following interesting details as to the amount of gelatine which can be obtained from wet hide pieces3-- ,,weight ,,of ,,wet ,,hide ,,pieces1 #b1abh ,,lbs4 ---------------------------------------- -- ,per cent4 ,weight of ,draught4 ,gallons4,gelatine in,gelatine4 ,solution4 ,lbs4 ---------------------------------------- -- #a #abfdh #fgge #hefd #b #abhif #fjeb #ghjd #c and #d mixed #acebj #iddf #abgfc -------- ---------- ,total #cijfd #biaca ---------------------------------------- -- ,percentage of gelatine on weight of wet skins #acfi4 ,a similar trial on the same class of wet hide pieces gave a yield of #acbc per cent4 ,two trials1 of a somewhat different class of wet hide pieces1 gave respectively #acaa and #abh per cent4 ,the temperature of the draught water should be approximately as follows3-- ------------------------------- ,draught4,at ,beginning4 ,at ,end4 ------------------------------- #a #abj ,f4 #aej ,f4 #b #acj ,f4 #afj ,f4 #c and #d #adj ,f4 #ahj ,f4 ------------------------------- ,in the final draught it is often necessary to use live steam at the finish1 but this should be avoided if possible4 ,the water contained in wet hide pieces varies from #gg to #ij per cent4 in the different pieces1 but in the bulk the average may be taken at #he per cent4 ,casein4--,casein is the nitrogenous principle of milk1 and belongs to the class of proteids which are definite compounds of oxygen1 hydrogen1 carbon1 and nitrogen1 forming the basis of the most important constituents of all animal fibres1 albumen1 casein1 and gluten4 ,a very pure form of casein is cheese made from skimmed milk4 ,casein belongs to that class of albumens which are soluble in water1 e4g41 egg albumen1 blood albumen or serum1 and lactalbumen1 or milk albumen2 these are mostly precipitated from solution by saturation with sodium chloride 7common salt7 or magnesium sulphate2 but they are all coagulated by heat4 ,by the action of rennet on milk the proteid or albumen principle is converted into a curd 7casein74 ,this curd1 when freed from fats1 is insoluble in water1 but is soluble in dilute acids1 or alkalies1 or alkaline carbonates1 from which substances1 however1 it is reprecipitated by acidulation4 ,instead of the above method1 casein may be precipitated from milk by saturation with sulphate of magnesia1 and washing the precipitate with a solution of that salt until the washings contain no albumen1 and then redissolving the prepared casein by adding water4 ,the salt still adhering to the precipitate enables it to dissolve4 ,on a large scale the casein is usually prepared by treating the milk with acid4 ,casein is readily dissolved by alkalies and alkaline carbonates1 borax1 boracic acid solution1 caustic soda1 and bicarbonate of soda4 ,starch4--,this substance is used in many classes of paper for improving the surface and finish4 ,it is added to the pulp in the beating engine in the dry form as powder1 or in the form of starch paste1 produced by boiling the starch in water4 ,the viscosity of the starch paste is somewhat increased by the addition of a small quantity of alkali1 but due care must be exercised in boiling1 which should only be carried out sufficiently to cause the starch granules to burst1 as any excessive boiling causes the starch paste to lose some of its viscosity4 ,the presence of starch in paper is detected by the blue coloration produced when the paper is dipped into a weak solution of iodine4 ,the determination of the exact percentage of starch in a paper is a matter of some difficulty4 ,silicate of ,soda4--,the precipitation of gelatinous silica upon the pulp in the beating engine is generally regarded as favourable to the production of a sheet of paper having what is known as a harder finish4 ,the precipitation is effected by adding a solution of silicate of soda to the beating engine1 with the subsequent addition of sufficient sulphate of alumina to react with the silicate of soda4 ,,analysis ,,of ,,commercial ,,alums4 7,griffin and ,little47 ---------------------------------------- ----------------- 7#a7 7#b7 7#c7 7#d7 ---------------------------------------- ----------------- ,insoluble in water #jje #ajfa #jaa #jef ,alumina 7,al#b,o#c7 #aedg #adif #aafd #afeh ,iron protoxide 7,fe,o7 #jjb #jac #jjf -- ,iron sesquioxide 7,fe#b,o#c7 #jjj #ajh #aag #jjd ,zinc oxide 7,zn,o7 -- -- -- -- ,soda 7,na#b,o7 #agb #jeg #dge #jef ,magnesia 7,mg,o7 -- -- #jde -- ,sulphuric acid 7,,so#c7 combined #cgbf #cgcf #ceih #ciag ,sulphuric acid 7,,so#c7 free -- #ajh #eac -- ,water by difference #dedh #cdba #djga #dcji ---------------------------------------- ----------------- #ajjjjajjjjajjjjajjjj ------------------------------- ------------------------- ,sizing test 7parts of dry neutral rosin size precipitated by one part of the alum7 #ccb #cdg #cai #cga ------------------------------- ------------------------- ,,table ,,showing ,,value ,,of ,,solutions ,,of ,,aluminium ,,sulphate4 ---------------------------------------- ----------- ,pounds per #ajj gallons4 ---------------------------------------- -- ,twaddell4,al#b,o#c4 ,,so#c4 ,sulphate of ,alumina containing #ae per cent4 ,al#b,o#c4 ---------------------------------------- --------- #a #ad #cc #ij #b #bh #fe #aij #c #db #ih #bhj #d #ef #acj #cgj #e #gj #afc #dgj #f #hd #aif #efj #g #ih #bbh #fej #h #aab #bfa #gej #i #abf #bid #hdj #aj #adj #cbf #icj #aa #aed #cei #ajcj #ab #afh #cia #aabj #ad #bjc #dgc #acej #af #bca #ech #aeej #ah #bfb #fjc #agbj #bj #bid #fhe #aifj #be #cga #hfe #bdgj #cj #ddh #ajdd #biij #ce #ecb #abdj #ceej #dj #fji #adbj #djej #de #fhf #aeii #defj #ej #ggg #ahaj #eghj #ee #hfa #bjjf #egej #fj #ieb #bbah #fcej ---------------------------------------- --------- ,alum4--,alum is one of the most important substances required in the manufacture of paper1 its chief function relating to the sizing of paper4 ,various forms are utilised for this purpose1 the purest being sulphate of alumina1 required for high grade papers1 and the cheaper form known as alum cake1 for news and common printing4 ,the alum is manufactured on a large scale by heating china clay or bauxite with sulphuric acid4 ,this reaction gives sulphate of alumina together with silica4 ,if the mass is heated to dryness1 it is sold under the name of alum cake4 ,if the mass is extracted with hot water and the insoluble silica filtered off1 the solution can be evaporated down for the production of sulphate of alumina1 which is sold in the form of large cakes or in the form of crystals4 ,by careful selection of raw material a sulphate of alumina can be prepared almost entirely free from iron4 ,the presence of the latter is undesirable1 since on exposure to air the sulphate of iron produced during the manufacture of the alum is slowly oxidised and turns brown4 ,ultimately this affects the colour of the finished paper4 ,alum is added to solutions of animal size or gelatine in order to thicken the solution and render it more viscous4 ,it also acts as a preservative1 and is used for regulating the absorption of the gelatine by the paper1 the penetration effects being materially varied by the extent to which the alum is utilised4 ,in the process of engine sizing1 a term applied to the application of rosin size on account of the fact that the process is completed in the beating engine1 alum plays an important part4 ,the mere addition of the prepared rosin soap to the mixture of pulp and water in the beating engine does not size the paper1 but the alum precipitates the rosin from its solution1 producing a complex mixture said to consist of resinate of alumina and free rosin particles1 and subsequently the heat of the paper machine drying cylinders renders the paper more or less impermeable to moisture4 ,the appearance and tone of paper1 more particularly of coloured papers1 are brightened by the use of an excess of alum over and above that necessary to precipitate the rosin soap4 ,rosin ,size4--,this substance is used chiefly for the sizing of news and cheap printing papers1 and is also employed together with gelatine for the commoner writing papers4 ,it is prepared by boiling rosin with carbonate of soda under various conditions4 ,rosin1 sometimes called colophony1 is obtained from the sap of certain firs and pine trees4 ,this on distillation yields spirits of turpentine1 leaving behind as a residue the mixture of substances to which is given the name rosin4 ,it behaves as an acid1 and therefore will combine with certain alkaline oxides1 producing soluble resinates4 ,the nature of the rosin soap used in the paper mill varies according to the conditions under which the size is prepared4 ,if a large proportion of rosin is used1 then the size obtained consists of a mixture of resinate of soda together with free rosin dissolved in the solution4 ,if the proportion of rosin is small compared with the amount of carbonate of soda1 the composition of the final mixture is quite different4 ,the difference in treatment results in the formation of-- 7,a7 ,neutral ,size1 prepared by boiling a known weight of rosin with sufficient alkali to combine with it and form a neutral resinate of soda4 ,theoretically this may be obtained by using #fcj parts of rosin to #ajj parts of soda ash4 ,it is doubtful how far the reaction is completed so as to produce an exactly neutral solution containing only resinate of soda4 7,b7 ,acid ,size4--,when the proportion of rosin is largely increased the soda becomes converted into the alkaline resinate1 and the excess of rosin is gradually dissolved in the resinate formed4 ,the practical operations necessary for the preparation of the size are comparatively simple4 ,in the case of size containing relatively small percentages of free rosin1 the boiling is conducted in open vessels1 but for the manufacture of rosin size containing large proportions of free rosin boiling under pressure in closed vessels must be resorted to4 ,with the open pan process a steam jacketed pan is used1 and the required quantity of alkali1 dissolved in water1 is placed therein and heated to boiling point4 ,the rosin well powdered is added in small quantities from time to time1 this being effected cautiously in order that the carbonic acid gas set free during the process may readily escape4 ,the rosin is generally completely saponified after four or five hours' boiling4 ,it is then passed through strainers into store tanks1 from which it is drawn into the beating engines as required4 ,in the case of rosin boiled under pressure a cylindrical vessel provided with a manhole at the top is used4 ,the correct amounts of alkali and water are put into the digester1 and also the rosin in a powdered form1 the digester being fitted with a perforated plate placed about two feet above the bottom of the vessel in order to prevent the rosin forming into a hard mass at the bottom of the digester4 ,it is possible in this way to manufacture a thick size containing #cj or #dj per cent4 of free rosin and a comparatively small proportion of water4 ,many paper mill firms prefer to purchase such size ready made4 ,the most recent modification of the ordinary rosin size is a compound prepared by treating rosin with silicate of soda4 ,this alkali dissolves rosin readily1 and the soap obtained when suitably diluted with water decomposes in the beating engine on the addition of aluminium sulphate1 with the precipitation of a gelatinous silica which assists in hardening the paper4 ,bacon has patented a process in which powdered rosin is melted down with dry crystalline silicate of soda4 ,the resultant product is ground to a fine powder1 which is then ready for use4 ,it dissolves easily in water1 and when decomposed with the proper proportion of alum gives a gelatinous viscous mass said to have excellent sizing properties4 ,the advantages of a dry powdered rosin size readily soluble in water are obvious4 ,loading4--,the term loading is applied to the various substances which are employed for the purpose1 as it is commonly supposed1 of making paper heavy4 ,but china clay and similar materials are not added simply in order to give weight to the paper1 since they serve to produce opacity and to improve the surface of papers which could not be satisfactorily made unless such materials were used4 ,examination of ,paper for ,loading4--,if a piece of paper is crumpled up1 placed in a small crucible1 and then ignited until all the carbonaceous matter has been burnt off1 a residue is left in the crucible which may be white or coloured4 ,this is usually termed the ash of the paper4 ,the amount of ash present is determined by taking a weighed quantity of paper and weighing the residue obtained4 ,special appliances can be obtained for making rapid determinations of the ash in paper1 but for occasional analyses they are not required4 ,china ,clay4--,this is the best known and most commonly used loading4 ,the purest form of this material is kaolin1 a natural substance formed by the gradual decomposition of felspathic rocks arising from exposure to the long-continued action of air and water4 ,the clay occurs in great abundance in ,dorset1 ,cornwall1 and ,devon1 the southern counties in ,england1 where the most famous deposits are found4 ,the natural mineral is levigated with water1 and the mixture allowed to flow through a series of settling ponds1 so that the clay gradually settles in the form of a fine deposit4 ,the clay is dried and packed in bags4 ,its value is controlled largely by the purity of its colour and its freedom from grit and sand4 ,it is essentially a silicate of alumina1 having the approximate composition-- ,silica 7,si,o#b7 #dcjj ,alumina 7,al#b,o#c7 #cejj ,combined water #ajjj ,moisture and impurities #abjj ------ #ajjjj ,the specific gravity of the dry substance is #bej4 ,it is utilised as a loading in all kinds of paper1 and forms also the main ingredient in the coating found on ordinary art and chromo papers4 ,ash containing ,china ,clay4--,in news1 cheap printings1 and common art papers the ash almost invariably contains china clay4 ,this substance is insoluble in dilute acids1 but is acted upon by concentrated sulphuric acid when digested for some time4 ,a simple test for the presence of china clay in ash is the blue coloration which is obtained when the ash after being ignited is gradually heated with a few drops of solution of cobalt nitrate4 ,china clay can be decomposed by fusion with carbonate of soda in a crucible4 ,by this means silicate of alumina is decomposed1 and the alumina goes into solution1 the silica remaining as an insoluble residue4 ,the filtered solution is boiled with an excess of ammonia which gives a gelatinous precipitate of aluminium hydrate4 ,sulphate of ,lime4--,this compound is valued chiefly for its brilliancy of colour1 being used in high-class papers4 ,it is slightly soluble in water1 to the extent of about #bc lbs4 in #a1jjj gallons1 and this fact must be taken into account when the material is added to the pulp in the beating engine4 ,it occurs naturally in a variety of forms1 such as gypsum1 alabaster1 selenite1 the first of which when finely powdered is sold to the paper-maker as gypsum1 powdered plaster1 and under other fancy names4 ,it can be prepared artificially by adding sulphuric acid to solutions of calcium salts2 and the precipitated product so obtained is sold as terra alba1 pearl hardening1 satinite1 mineral white1 etc4 ,the tests for sulphate of lime in paper ash are based upon the following reactions3-- ,calcium sulphate is soluble in dilute hydrochloric acid4 ,the addition of a few drops of barium chloride to the solution produces a dense heavy precipitate1 indicating the sulphate4 ,a small quantity of ammonium oxalate solution added to another portion of the dissolved calcium salt previously neutralised with ammonia produces a precipitate and indicates calcium4 ,a microscopic test of paper for the presence of sulphate of lime is based upon the slight solubility of the salt in water4 ,the paper is boiled with some distilled water4 ,the water is evaporated to a small bulk and transferred to a glass slip1 and the gradual formation of characteristic sulphate of lime crystals can be seen by means of the microscope as the water cools down4 ,french ,chalk4--,this material is prepared by grinding talc into a fine powder1 and possesses a good colour and a somewhat soapy feel4 ,it is a silicate of magnesia1 having the approximate composition-- ,silica 7,si,o#b7 #fbjj ,magnesia 7,mg,o7 #ccjj ,water #dcj ,traces of oxides1 etc4 #jgj ------ #ajjjj ,other silicates of magnesia used for paper-making are agalite and asbestine1 the latter being a finely ground asbestos4 ,the composition of asbestos is approximately-- ---------------------------------------- -------- -- ,italian4 ,canadian4 ---------------------------------------- -------- ,lime and magnesia #chj #ccj ,silica #dbj #daj ,oxides of iron and alumina #ej #abj ,total water #acj #abj ,traces of soda1 etc #bj #cj --------------------- #ajjjj #ajjjj ---------------------------------------- -------- ,,chapter ,,ix ,,the ,,process ,,of ,,beating ,introduction4--,the process of beating has for its object the complete breaking down of the bleached pulp to the condition of single fibres1 and the further reduction of the fibres1 when necessary1 into smaller pieces4 ,the disintegration of the material is essential for the production of a close even sheet of paper1 and the amount of beating required varies greatly according to the nature of the raw material1 and the class of paper to be produced4 ,the textile trade1 on the other hand1 depends on a raw material composed of strong fibres1 or of filaments characterised by great length1 and any processes of treatment which tend to reduce the length of such fibres are carefully avoided1 and it is therefore obvious that fibres which are of no value for textile purposes can be appropriated for paper-making4 ,condition of ,fibres4--,the great differences in the physical characteristics and structure of the fibres employed for paper-making suggest that the possible variations in the final product obtained by beating are very numerous4 ,this is a well-known fact1 and it is further to be noted that this mechanical operation brings about not merely alterations of a physical order1 but introduces some interesting and important chemical changes4 ,of the better-known materials linen1 with an average fibre length of #bh mm41 the structure of which lends itself to considerable alteration by beating1 is in marked contrast to esparto1 the fibre length of which is only #ae mm4 ,if the process of beating a linen rag merely resulted in the cutting of all the fibres of #bh mm4 long into short fragments of #ae mm41 there would be nothing remarkable in it1 but the changes which occur in reducing the long linen fibre to #ae or #bj mm4 are of a far more important character than this4 ,early ,methods4--,in the early days of paper-making the disintegration of the half-stuff was effected by a true beating process1 the rags being subjected to the action of heavy stampers1 which broke up the mass of tangled fibre into a uniform pulp4 ,the fibres for the most part retained their maximum length in this operation1 which was exceedingly slow and tedious1 though at the same time giving a sheet of paper of remarkable strength4 ,the nearest imitation of these old-time rag papers is to be seen in the well-known ,japanese papers1 which are extraordinarily strong4 ,some of these the writer has examined in order to determine the length of the fibre4 ,the sheets when held up to the light appear cloudy and wild owing to the presence of the long fibres1 which have only been separated or teased out by the primitive methods of beating used1 and not completely disintegrated4 ,conditions of ,beating4--,about ,a4,d4 #agjj there began a great epoch in the history of paper-making4 ,with the invention of the ,hollander engine about ,a4,d4 #afgj1 the process of disintegration was greatly hastened1 because it was possible to reduce the half-stuff much more readily4 ,the substitution of the idea of plain beating by a principle which combined the gradual isolation of the individual fibres with a splitting up of those fibres lengthwise and crosswise was not only an advantage in point of economy of time and cost1 but also a material advance in the possibilities of greater variations in the finished paper4 ,the conditions of the process of beating carried out with a ,hollander permit of considerable alteration1 so that these changes in the fibre are not surprising when properly understood4 ,in fact1 it is now conceded that a close study of the theory and practice of beating is likely to bring about still more remarkable improvements in this important department of the paper-maker's work4 ,the quality and character of the paper made may be varied with-- 7#a7 ,the origin of the raw material1 e4g41 rags1 esparto1 or wood2 7#b7 ,the condition of the material1 e4g41 old or new rags1 green or mature esparto1 mechanical or chemical wood pulp2 7#c7 ,the time occupied in beating1 e4g41 four hours for an ordinary rag printing and twelve hours for a rag parchment2 7#d7 ,the state of the beater knives1 e4g41 sharp tackle for blottings and dull tackle for cartridge papers2 7#e7 ,the speed of the beater roll1 also its weight2 7#f7 ,the rate at which the beater roll is lowered on to the bedplate2 7#g7 ,the temperature of the contents of the engine4 ,the ,beater ,roll4--,if the beater roll is fitted with sharp knives1 and this is put down close to the bedplate quickly1 the fibres are cut up short1 and they do not assimilate the water4 ,if the roll is fitted with dull knives1 or tackle1 as it is sometimes called1 and it is lowered gradually1 the fibres are drawn and bruised out without being greatly shortened4 ,in this condition the stuff becomes very wet1 or greasy1 as it is termed4 ,the cellulose enters into association with water when beaten for many hours1 and the pulp in the beating engine changes into a curious greasy-like mass of a semi-transparent character4 ,rag pulp beaten for a long time produces a hard1 translucent1 dense sheet of paper4 ,flax thread beaten #dh to #fj hours is used in practice for the manufacture of gramophone horns and similar purposes4 ,soft porous papers like blottings1 filtering papers1 heavy chromos1 litho papers1 antiques1 light printings1 are made from pulps which are beaten quickly with the roll put down close to the bedplate soon after the stuff has been filled in4 ,with strong1 dense1 hard papers1 such as parchments1 banks1 greaseproofs and the like1 the pulp is beaten slowly and the roll lowered gradually4 ,the nature of the pulp and the time occupied in beating are also important factors in producing these different papers1 three to four hours being ample for an ordinary wood pulp printing1 whereas a wood pulp parchment requires seven to eight hours4 ,beating ,pulps ,separately4--,the use of esparto and wood pulp in conjunction with one another1 or blended with rag1 has introduced new problems into the question of beating4 ,perhaps the most important of these is the advisability of beating the pulps separately and eventually passing them through a mixer of some kind before discharging into a stuff chest4 ,the necessity for differentiating the amount of beating is already partly recognised when very dissimilar pulps1 such as strong rag and esparto1 are blended1 but the whole subject ought to be carefully studied by the paper-maker and investigated on its merits from the standpoint of beating effects1 apart from questions of cost and expediency4 ,the former fully understood and exhaustively examined by practical tests would of course only be developed if proved to be advantageous4 ,the field of research in this direction has not yet been seriously explored4 ,with the enormous consumption of wood pulps of varying quality made from many different species of wood by several processes1 there is ample room for interesting and profitable enquiry1 particularly as the types of beating engine are so numerous4 ,the effects produced by the ,hollander1 the refiner1 the edge runner1 the stone beater roll1 and other mechanisms1 are all of varying kinds4 ,,effect ,,of ,,prolonged ,,beating4 ,the importance of a knowledge of the precise effects produced by the beating of pulp cannot be emphasised too much1 and any contributions to the subject along the lines of special research will be welcomed by all students of cellulose4 ,illustration3 ,,fig4 #df4--;,cotton ,pulp beaten #h hours4 ,some experiments were conducted by the writer in #aijf with cotton rags1 in order to determine the results obtained by beating the pulp for a prolonged period under exact and specific conditions4 ,illustration3 ,,fig4 #dg4--;,cotton ,pulp beaten #cg hours4 ,the cotton rags1 of good quality1 were boiled with caustic soda in the usual way for six or seven hours1 at a pressure of #ae to #bj lbs41 washed and partially broken down in the rag breaker1 and finally bleached1 made into half-stuff1 and then transferred to a ,hollander beating engine4 ,the particular conditions specified for the beating operation were that the beaterman should manipulate the pulp according to his usual routine for the manufacture of the paper which he was accustomed to make from these rags4 ,in this case the routine process meant beating for eight hours1 by which time the pulp was ready for the paper machine4 ,in the ordinary course the pulp would be discharged into the stuff chest1 and converted into a strong1 thin1 bank paper4 ,during the prolonged beating the pulp became very soft and greasy1 and when made up into sheets the paper as it dried exhibited remarkable differences in shrinkage1 the dry sheets obtained from pulp beaten thirty-seven hours being much smaller than those obtained from pulp beaten only four or six hours4 ,the actual shrinkage is shown in the following table3-- ---------------------------------------- --------------------- ,relative ,hours4 ,area of ,sheet4 ,loss of ,area4 ,areas4 ,shrinkage ,sq4 mm4 ,sq4 mm4 ,deckle #ajj per cent4 ---------------------------------------- --------------------- #j #bf1chdj -- #ajjj -- #d #bf1jgfj #cjhj #ihi #aa #f #be1ebja #hfci #ifg #cc #h #be1afjj #a1bbdj #ied #df #aj #bd1gidh #a1ehib #ici #fa #ac #bd1dfgd #a1iaff #ibh #gb #ae #bd1baeb #b1afhh #iah #hb #ag #bd1jbdj #b1cfjj #iji #ia #ai #bc1fafb #b1gfgh #hif #ajd #ba #bc1fafj #b1gfhj #hif #ajd #bc #bc1eceg #b1hdhc #hic #ajg #be #bc1cbii #c1jeda #hhe #aae #bg #bb1ibje #c1dfce #hfi #aca #bi #bb1hcab #c1eebh #hfe #ace #ca #bb1dibi #c1hiaa #hec #adg #cc #ba1iagb #d1dffh #hca #afi #ce #ba1bbfa #e1aegi #hje #aie #cg #bj1gghh #e1fjeb #ghh #bab ---------------------------------------- --------------------- ,if these results are plotted in the form of a curve the relation between the period of beating and the shrinkage in area is clearly shown4 ,for the first twenty hours the shrinkage is proportional to the period of beating1 after which the curve assumes an irregular shape1 showing a tendency for shrinkage to proceed at a faster rate4 ,weight and ,substance of the ,paper4--,the shrinkage of the paper after prolonged beating indicates a closer and denser sheet1 so that for papers of equal thickness the weight per unit area was much greater in the case of the pulp beaten for the full period4 ,the results obtained are very interesting1 and the following summary for a few of the readings obtained will serve to show the alteration effected4 ---------------------------------------- ------------------------- ,weight of ,thickness of ,grams per ,lbs4 per ream ,hours4 #bj1jjj sq4 mm4 ,sheet4 sq4 metre4 #dhj sheets1 ,grams4 mm4 #bj #cj4 ---------------------------------------- ------------------------- ,class ,a #h-aj hrs4 #ahge #ahc #icge #chbc ,class ,b #ai-ba hrs4 #bjdc #ahi #ajbae #dafe ,class ,c #cc-ce hrs4 #bbjc #ahi #aajae #ddic ---------------------------------------- ------------------------ ,sizing and ,glazing ,effects4--,the behaviour of the waterleaf paper after sizing and glazing gave some interesting results4 ,in the first place1 the effect of the altered density of the paper is strikingly shown by the amount of the size absorbed4 ,certain selected sheets were passed through a solution of ordinary gelatine in the usual way1 and subsequently dried4 ,the amount of gelatine absorbed differs in a remarkable degree1 as shown in table4 ,tensile ,strength of the ,paper4--,it is interesting to note that the tensile strength of the waterleaf papers appears to remain fairly constant throughout the whole period of beating4 ,but this uniformity is greatly altered by the operations of sizing and glazing4 ,,percentage ,,of ,,air-,,dry ,,gelatine ,,absorbed ,,by ,,the ,,waterleaf ,,sheets4 ---------------------------------------- -------------- ,percentage of ,size absorbed4 ,hours4 --------------------------------- ,mean4 #ast ,trial4 #bnd ,trial4 #crd ,trial4 ---------------------------------------- ------------ #h #ee #fj #fb #ei #aj #ed #fh #fe #fb #ai #ch #ej #de #dd #ba #dh #ci #df #dd #cc #bg #ag #bd #bc #ce #bd #ai #ag #bj ---------------------------------------- ------------ ,these results are rather remarkable4 ,the prolonged beating does not seem to have affected the tensile strength of the waterleaf1 and the practical loss of strength which actually occurs in the more completely finished paper does not manifest itself until after the sizing process4 ,the importance of the gelatine as a factor in the ultimate strength is thus clearly and strikingly demonstrated4 ,,tests ,,for ,,strength ,,on ,,original ,,waterleaf ,,paper4 ---------------------------------------- -- ,mean result of,mean ,strength ,hours4 ,readings4 of the ,paper4 ,lbs4 ,lbs4 ---------------------------------------- -- #h a #ada #aba b #aja #aj a #aed #acb b #aji #ai a #afe #adj b #aad #ba a #aeb #adj b #abh #cc a #acd #abd b #aad #ce a #ade #acf b #abg ---------------------------------------- -- ,,tests ,,for ,,strength ,,on ,,papers1 ,,sized ,,only4 ---------------------------------------- -- ,mean result of,mean ,strength ,hours4 ,readings4 of the ,paper4 ,lbs4 ,lbs4 ---------------------------------------- -- #h a #bbg #bjj b #agc #aj a #bhe #bcb b #ahj #ai a #bbe #baj b #aie #ba a #bfj #bag b #age #cc a #aej #aej b #aej #ce a #adb #aec b #afe ---------------------------------------- -- ,,tests ,,for ,,strength ,,on ,,paper ,,sized ,,and ,,glazed4 ---------------------------------------- -- ,mean result of,mean ,strength ,hours4 ,readings4 of the ,paper4 ,lbs4 ,lbs4 ---------------------------------------- -- #h a #beh #bcf b #bad #aj a #bhd #bcf b #ahi #ai a #bgj #bbi b #ahi #ba a #bdi #bbg b #bjf #cc a #afa #aeb b #add #ce a #age #afb b #aej ---------------------------------------- -- ,it may also be noticed that the strength of the finished paper after twenty hours' beating1 as in class ,b1 is equal to that of the paper after nine hours' beating1 as in class ,a4 ,this is curious1 especially in view of the fact that the percentage of gelatine in the papers of class ,b4 is only #dd per cent4 as against #fj per cent4 in class ,a4 ,the relation of the percentage of gelatine to the period of beating thus becomes a matter of interest1 and well worth investigation4 ,the figures are suggestive of further experimental research along definite lines4 ,illustration3 ,,fig4 #dh4--,plan and ,sectional ,elevation of a ,hollander4 ,developments in ,beating ,engines4--,since the introduction of the ,hollander beating engine1 about ,a4,d4 #afgj1 other types of beater almost too numerous to mention have been devised to supersede it1 but the fact remains that the principle of the original ,hollander and its general design are still adhered to in the engines used by paper-makers for high-class work4 ,the alterations and improvements which have taken place during the last fifty years relate chiefly to the modifications naturally arising from the introduction of fibres not requiring such drastic treatment as rags4 ,the machines now in use for reducing half-stuff to beaten pulp ready for the paper machine may be classified as follows3-- 7#a7 ,beaters of the ,hollander type1 in which the circulation of the pulp in the engine and the actual beating process are both effected by the beater roll4 7#b7 ,beaters of the circulator type1 in which the movement of the pulp is maintained by a special contrivance1 and the beater roll used only for beating4 7#c7 ,beaters of the stone roll type in which the roll and bedplate are either or both composed of stone1 granite1 or similar non-metallic substance4 7#d7 ,refiners1 containing conical shaped beater rolls working in a conical shell fitted with stationary knives4 ,illustration3 ,,fig4 #di4--;,beating ,engine with ,four ,beater ,rolls4 ,the ,hollander4--,this beating engine in its simplest form consists of an oval shaped trough1 divided into two channels by a midfeather1 which does not1 however1 reach completely from one end to the other4 ,in one of the channels the bed of the trough slopes up slightly to the place where the bedplate is fixed4 ,the bedplate consists of a number of stout metal bars or knives firmly fastened into an iron frame1 which lies across this channel4 ,the beater roll1 a heavy cast-iron roll provided with projecting knives or blades arranged in clumps of three around the circumference1 and supported on bearings at each side of the engine1 revolves above the bedplate with the knives adjusted to any required distance from it1 the raising or lowering of the beater roll for this purpose being effected by the use of adjustable bearings4 ,the bed of the trough behind the beater roll rises sharply up from the bedplate and then falls away suddenly1 as shown in the diagram1 forming the backfall4 ,when the engine is in operation the mixture of water and pulp is drawn between the knives and circulated round the trough4 ,the material is disintegrated into fibres of the required condition1 discharged over the backfall1 and kept in a state of continual circulation1 and the beating maintained until the stuff has been sufficiently treated4 ,the dimensions of the engine vary according to the capacity1 which is usually expressed in terms of the amount of dry pulp the beater will hold1 and the following figures may be taken as giving the average sizes3-- ---------------------------------------- --------- -- #b cwt4 ,engine4 #e cwt4 ,engine4 ---------------------------------------- --------- ,length #aa ft4 #j in4 #af ft4 #j in4 ,width #e ft4 #f in4 #h ft4 #j in4 ,depth 7average7 #b ft4 #c in4 #b ft4 #i in4 ,diameter of roll #c ft4 #f in4 #c ft4 #f in4 ---------------------------------------- --------- ,sundry modifications in the form and arrangement of the beater have been tried from time to time4 ,in #ahfi ,granville patented the substitution of a second beater roll in place of the stationary bedplate for the purpose of hastening the operation4 ,repeated attempts have been made to construct a beating engine with two or more rolls1 but it is evident that such a device could hardly succeed1 since it would be impossible to ensure proper adjustment of the rolls1 and in that case one roll might be doing all the work4 ,the first machine of this type was patented in #ahgb by ,salt4 ,similar beaters were devised by ,forbes in #ahhj1 ,macfarlane in #ahhf1 ,pickles in #ahid1 who proposed to use three rolls1 and ,partington in #aija4 ,hoffman describes a beating engine which was working in ,america containing four rolls1 as shown in the diagram4 ,the ,umpherston4--,a notable modification of the ,hollander1 having an arrangement by which the two channels of the engines are placed under one another1 and one which is largely used for fibres1 is the ,umpherston4 ,several engines differing in detail1 but embodying the same principle1 have been built in imitation of this one4 ,illustration3 ,,fig4 #ej4--,umpherston ,beater4 ,bedplates of large working surface were first tried in ,england by ,cooke and ,hibbert1 in #ahgh1 but in practice it has been found that no serious deviations from the narrow type of plate are of much value4 ,as a matter of fact it is held by some paper-makers that one or two knives would be sufficient if they could be relied on to keep true and in proper adjustment4 ,the ,circulating ,type of ,beater4--,the addition of some device for keeping the pulp in circulation apart from the action of the roll has received considerable attention4 ,the early experiments in this direction with the ,hollander led ultimately to the construction of the engine of the circulator type mentioned in class #b4 ,illustration3 ,,fig4 #ea4--,section of ,umpherston ,beating ,engine4 ,thus1 in #ahgb1 ,nugent patented a special paddle to be used in the ,hollander1 by which the pulp in the trough of the beater was impelled towards the roll4 ,many other plans were tried for this purpose1 and details can be seen in the ,list of ,patents 7see page #aib74 ,the introduction of the beaters with special means of circulating the pulp was found to be of the greatest service in the treatment of stuff like esparto and wood pulp1 since these materials did not require the drastic measures necessary with rag pulp4 ,in #ahij several engines of this class were being adopted1 amongst which may be mentioned ,hemmer's1 ,reed's and ,taylor's4 ,the pulp discharged from the beater roll was drawn through an independent pipe or channel by means of an ,archimedean screw1 or a centrifugal pump4 ,stone ,beater ,rolls4--,the substitution of stone for metal in the roll and bedplate of the engine brings about some remarkable changes in the nature of the beaten stuff4 ,the fibre is submitted to the action of rough surfaces rather than that due to the contact of sharp edges1 with the result that the disintegration is much more rapid1 and produces a wet working pulp suitable for imitation parchments and similar papers4 ,the latest materials used for this purpose are basalt lava stone in ,germany1 and carborundum in ,america4 ,illustration3 ,,fig4 #eb4--,nugent's ,beating ,engine with ,paddles for ,circulating the ,pulp4 ,care is necessary in the manipulation of these beaters to prevent fracture of the stone parts4 ,in the ,wagg ,jordan engine this danger is materially reduced by the construction of the working parts4 ,refiners4--,in these engines the beater roll is a conical shaped drum carrying the knives1 which revolve inside a conical shell completely lined with fixed knives4 ,the fibres are thus cut up to the desired length1 but before discharge from the engine they pass between two circular discs1 one stationary and the other revolving in a vertical position4 ,the effect of the discs is to tear or bruise the fibres rather than to cut them4 ,the refiner is best employed to clear or brush out the mass of pulp after a certain amount of preliminary treatment in the beater1 as the refiner cannot produce the effects obtained by actual beating as in the ,hollander4 ,illustration3 ,,fig4 #ec4--;,a ,tower ,beating ,engine with ,centrifugal ,pump for ,circulating ,pulp4 ,power ,consumption4--,the long treatment required to thoroughly pulp a strong material demands a great amount of power4 ,engines differ considerably in their power consumption1 and comparisons are frequently made in terms of the power required to beat a given weight of pulp4 ,but this is not always a true criterion of efficient work4 ,some types of beater are suitable for producing certain results1 and the mere substitution of a beater consuming less power is worse than useless unless it can be shown that the same effects are being obtained4 ,the efficiency of the ,hollander for the beating of rag pulp1 in spite of the high power consumption1 is a case in point4 ,illustration3 ,,fig4 #ed4--,working ,parts of a ,modern ,refining ,engine4 ,with this factor properly considered1 the power required for beating becomes an interesting study4 ,many detailed experiments have been published from time to time1 the most recent being those described by ,beadle4 ,,patents ,,taken ,,out ,,in ,,connection ,,with ,,beating ,,engines4 #ahee4 ,,park 7#aagj74--;,a small steam engine was attached to the shaft of the beater roll1 so that it could be driven direct4 #ahef4 ,,kingsland 7#bhbh74--;,a form of refiner in which the pulp was beaten by a vertical disc rotating in an enclosed case4 #ahfj4 ,,jordan 7#gib74--;,a machine devised for mixing size with pulp1 made like a conical refining engine1 the rubbing surface being provided with teeth or cutters4 #ahfj4 ,,jordan 7#bjai74--;,an engine of the refiner type1 constructed with a conical drum rotating in a conical casing4 ,the knives at the larger end of the drum are placed closer together than those on the smaller end4 #ahfc4 ,,park 7#aach74--,two beaters placed side by side are driven by one steam engine placed between them1 the operations being so timed that one rag engine is used for breaking while the other is finishing4 #ahfd4 ,,ibotson 7#biac74--,the pulp is passed continuously from one engine roll to another1 or from one part of a beater roll to another part of the same roll through slotted plates4 #ahff4 ,,roeckner 7#adj74--;,a beating engine of the refiner type with conical drum and casing4 #ahff4 ,,berham 7#cbii74--;,a beating engine of the conical type with the beater roll rotating vertically instead of horizontally4 #ahfg4 ,,crompton 7#dhb74--;,device for raising the bars in the beater roll as the edge of the plate wears away4 #ahfg4 ,,wood 7#iad74--,modification in the form of the beater bars 7of little importance74 #ahfg4 ,,edge 7#cfgc74--,the knives of the beater roll distributed at equal distances apart all round the roll1 alternated with strips of wood4 #ahfi4 ,,granville 7#ajda74--,substitution of a second beater roll for the stationary bed-plate1 the knives being set spirally round the roller4 #ahfi4 ,,newell 7#bije74--,weight of the beater roll counterpoised to allow of the exact regulation of the pressure on the stuff in the beating engine4 #ahgj4 ,,rose 7#iig74--;,an intercepting plate fixed to the cover of the beating engine which causes that part of the stuff which was usually carried right round by the roll to fall back behind the backfall4 #ahgj4 ,,bentley ,,and ,,jackson 7#afcc74--;,a beater roll having the same width as the engine1 and provided with a cover fitted with a pipe which conducted the material back to the front of the roll4 #ahga4 ,,patton 7#accf74--;,bottom of beating engine curved in order to prevent the stuff settling or accumulating at any portion of the machine4 #ahgb4 ,,salt 7#aija74--;,a beating engine of usual type1 but having two beater rolls and two drum washers1 one pair in each of the two channels4 #ahgc4 ,,gould 7#gfi74--;,a curious engine with horizontal shaft having a circular disc at the lower end1 fitted with knives on the under-surface1 which are in contact with fixed knives lying at the bottom of the vessel4 ,the circulation of the pulp is effected by the centrifugal force generated4 #ahgc4 ,,martin 7#cgea74--;,a beating engine with two rolls in the same trough1 the first roll working in conjunction with a smooth surfaced beating roll1 the other being in contact with a bedplate of the usual type1 the object of the first roll being to partially disintegrate the material without danger of choking4 #ahgd4 ,,johnstone 7#cgjh74--;,a pulping engine in which the rubbing action of two grindstones one upon the other is utilised as a means of beating4 #ahgf4 ,,gardner 7#cjg74--;,a beating engine in which the beater roll is conical in shape1 working vertically in contact with the bottom of the beating engine1 which is also conical in shape1 the engine itself being circular4 #ahgh4 ,,cooke ,,and ,,hibbert 7#djfh74--,the bedplate constructed in the form of a circular segment with a much larger face than usual1 and capable of adjustment1 the beater roll itself being fixed in the bearings4 #ahhj4 ,,forbes 7#fib74--;,a long oval shaped beating engine divided into three channels instead of two4 ,in the two outer channels are placed beater rolls and drum washers4 ,the stuff discharged over the backfalls from the two beating engines flows down the central channel and is circulated by a special paddle constructed in such a manner as to deliver the pulp in two equal streams into the outer channels to each of the beater rolls4 #ahhj4 ,,umpherston 7#aaej74--;,an engine constructed with a passage below the backfall so that the stuff circulates in a trough underneath the beater roll1 the object being to ensure more effective treatment and to save floor space4 #ahhc4 ,,aitchison 7#echa74--;,a beating engine of usual form1 but with the beater roll made conical in shape with the larger circumference outwards1 and the bedplate placed on an incline parallel with the knives on the beater roll4 #ahhd4 ,,mayfield 7#bjbh74--,the backfall of the beating engine is of entirely different construction to the ordinary machine1 for the purpose of improving the circulation4 #ahhd4 ,,hoyt 7#aaagg74--;,an engine resembling the ,umpherston1 but with a larger roll1 the diameter of which is equal to the full depth of the engine1 the backfall being in a line with the axis of the beater roll4 #ahhe4 ,,jordan 7#gaef74--;,additions to the ,jordan engine for admitting water and steam to the engine as required4 #ahhe4 ,,korschilgen 7#idcc74--,the beater roll made of stone or of metal with a stone casing furnished with ribs or knives placed close together4 #ahhf4 ,,hibbert 7#dbcg74--;,a beating engine fitted with an ordinary beater roll1 and having in addition a heavy disc rotating vertically1 the disc being fitted with knives on one surface which rotate in contact with knives fixed on a stationary disc4 #ahhf4 ,,kron 7#ihhe74--;,a device for securing better circulation of the pulp1 the stuff leaving the beater roll being divided into two streams which are brought together again in front of the roll4 #ahhf4 ,,horne 7#ajbcg74--;,a long rectangular vessel with a large beater roll at one end1 contrived so as to force the pulp leaving the beater roll to pass down a partition separating it from the pulp going towards the beater roll4 #ahhf4 ,,macfarlane 7#aajhd74--;,an engine fitted with two beater rolls which rotate in opposite directions1 the stuff being mixed between them4 #ahhg4 ,,nacke 7#gdf74--;,a centrifugal circulating wheel rotating horizontally in the centre of the beating engine is used in combination with a parallel cutting disc4 #ahhg4 ,,marshall 7#ahjh74--;,a conical refiner having in addition at its large end a pair of grinding discs fitted with knives and rotating vertically4 #ahhg4 ,,voith 7#fagd74--;,an alteration to the covers of the beater rolls which prevent stuff from being carried round the cylinder1 and cause it to pass over the backfall freely4 #ahij4 ,,hemmer 7#agdhc74--;,a beating engine provided with a separate return channel for the pulp1 the circulation through the channel being effected by a small centrifugal pump4 #ahij4 ,a4 ,e4 ,,reed 7#aiajg74--;,a beating engine in which the pulp discharged over the backfall is delivered to the front of the beater roll by a screw propeller4 #ahia4 ,,karger 7#aaefd74--;,a beater similar to the ,umpherston1 but provided with a circulating roll fitted with radial projections which delivers the stuff to the front of the beater roll4 #ahib4 ,,taylor 7#gcig74--;,a beating engine in which the beater roll operates in a closed chamber above the vat full of pulp1 the stuff being continually circulated by a centrifugal pump which draws the stock from the bottom of the vat and delivers it to the beater roll4 #ahib4 ,,annandale 7#iagc74--;,a conical-shaped beating engine with the beater roll rotating in a vertical position2 the larger end of the cone being downwards4 #ahib4 ,,umpherston 7#aegff74--;,an addition to the beating engine arranged so that two fixed bedplates are used instead of one4 #ahib4 ,,miller 7#aeidg74--;,a machine in which two fixed bedplates are used1 one below the beater roll and one above1 the engine being fitted with suitable baffle plates to ensure proper circulation4 #ahic4 ,,pearson ,,and ,,bertram 7#aaief74--;,a special form of refining engine in which the pulp is subjected to the action of discs rotating vertically1 the knives being arranged radially on the disc4 #ahic4 ,,caldwell 7#aeccb74--;,a rotary beating engine in which the beating surfaces admit of accurate adjustment4 #ahid4 ,,cornett 7#ide74--;,an outlet is fixed to the beater roll casing close to the discharge from the bedplate1 so that the roll is not impeded by the weight of the pulp1 which is subsequently pumped to the front of the beater roll4 #ahid4 ,,shand ,,and ,,bertram 7#dacf74--;,a beating engine similar to the ,umpherston beater in which the beater roll is raised up out of the pulp and the circulation effected by means of a worm which delivers the pulp to the front of the beater roll4 #ahid4 ,,pickles 7#bjbee74--;,a beating engine somewhat similar to an ,umpherston1 but fitted with three beater rolls and bedplates4 #ahid4 ,,hibbert 7#bejdj74--;,a beating engine in which the pulp is beaten between two discs rotating vertically1 the pulp being brought between the discs through the hollow shaft of one of the discs4 #ahie4 ,,brown 7#afae74--;,an engine in which the beater roll and bedplate both revolve1 but in opposite directions1 and at different speeds in order to draw out the fibres4 #ahie4 ,,schmidt 7#bdgcj74--;,a device by means of which the pulp discharged from the beater roll is diverted into supplementary channels on either side which come together again in front of the beater roll4 #aijj4 ,,hadfield 7#bdfh74--;,an adjustable baffle board passing through the cover of the beater roll which prevents the pulp being carried round by the roll1 more or less4 #aijj4 ,,masson ,,and ,,scott 7#ecfg74--;,an improved form of ,taylor beating engine in which the chest of the engine is vertical instead of horizontal4 #aija4 ,,partington 7#bdfed74--;,a continuous elliptical trough provided with two beater rolls4 #aijb4 ,,picard 7#aifce74--;,improvements in the form of the propellers used for circulating the material4 #aijb4 ,,pope ,,and ,,mullen 7#bbjhi74--;,improvements in propellers for circulating the pulp4 #aijc4 ,,annandale 7#bfjab74--;,a new form of beating engine somewhat on the principle of a steam turbine4 #aije4 ,,bertram 7#agbg74--;,a beater similar to ,masson's tower beater1 but in which a pair of reciprocating wheels fitted with projecting knives are used instead of a centrifugal pump4 #aijg4 ,,wagg',s ,,jordan ,,engine 7#fghh74--;,a conical refiner fitted with specially arranged metal or stone knives4 ,,chapter ,x ,,the ,,dyeing ,,and ,,colouring ,,of ,,paper ,,pulp ,nearly all papers1 even those commonly regarded as white1 are dyed with some proportion of colouring matter4 ,with the ordinary writing and printing papers the process is usually confined to the addition of small quantities of pigments or soluble colours sufficient to tone the pulp and correct the yellow tint which the raw material possesses even after bleaching4 ,in the case of cover papers1 tissues1 and similar coloured papers1 the process is one of dyeing as it is generally understood4 ,the colouring matters which have been employed by the paper-maker are-- ,,pigments4 7,a7 ,added to the pulp in the form of mineral in a finely divided state4 ,yellow4--,this colour is obtained by the use of ochres1 which are natural earth colours of varying shades1 from bright yellow to brown4 ,red4--,ordinary red lead4 ,various oxides of iron1 such as ,indian red1 ,venetian red1 red ochre1 rouge4 ,blue4--,smalts--,an expensive pigment prepared by grinding cobalt glass4 ,ultramarine--,a substance of complex composition prepared by heating a mixture of china clay1 carbonate of soda1 sulphate of soda1 sulphur1 charcoal1 and sometimes quartz1 rosin and infusorial earth4 ,prussian ,blue--,a compound prepared by adding potassium ferrocyanide to a solution of ferrous sulphate4 ,brown4--,natural earth colours1 such as sienna1 umber1 ,vandyke brown4 ,black4--,lamp-black1 bone-black1 ,frankfort black4 7,b7 ,produced by the reaction of soluble salts upon one another when added to the pulp in the beating engine4 ,yellow4--,chrome ,yellow--,the paper pulp is first impregnated with acetate of lead1 and potassium or sodium bichromate added4 ,this precipitates the chromate of lead as a yellow pigment4 ,chrome ,orange--,the addition of caustic alkali to the bichromate solution converts the chrome yellow into an orange4 ,blue4--,prussian ,blue--,the paper pulp impregnated with iron salts is treated with potassium ferrocyanide4 ,the blue colour is at once obtained4 ,brown4--,iron ,buff--,a light yellow-brown colour due to the precipitation of ferrous sulphate by means of an alkali4 ,bronze4--,manganese chloride followed by caustic soda4 ,,soluble ,,colours4 7,a7 ,natural ,dyes4 ,these colouring matters are now seldom used4 ,yellow and ,brown4--,the vegetable extracts1 such as fustic1 quercitron1 cutch1 turmeric1 have practically all been replaced by aniline colours4 ,red4--,madder 7,turkey red71 ,brazilwood1 cochineal 7a dye obtained from dried cochineal insects74 ,safflower4 ,black4--,logwood1 used in conjunction with an iron salt4 ,cutch1 used with an iron salt4 7,b7 ,coal ,tar ,dyes4 ,the dyeing and colouring of paper pulp by means of the artificial organic substances has become a matter of daily routine1 the expensive natural dyes and the ordinary pigments having been almost completely superseded4 ,the numerous colouring matters available may be classified either by reference to their chemical constitution or simply on general lines1 having regard to certain broad distinctions4 ,if the latter classification is taken1 then the dyes familiar to the paper-maker may be divided into-- 7a7 ,acid dyes1 so called because the full effect of the colouring matter is best obtained in a bath showing an acid reaction4 7b7 ,basic dyes1 so called because the colour is best developed in an alkaline solution1 without any excess of mordant4 7c7 ,substantive dyes1 which do not require the use of a mordant1 as the colour is fixed by the fibre without such reagents4 ,some of the most frequently used colouring matters are shown in the accompanying table on page #bjb4 ,the distinction between acid and basic dye-stuffs is largely due to certain characteristics possessed by many of them4 ,thus magenta1 which is the salt of the base known as ,rosaniline1 belonging to the basic colouring matters1 a group of dyes which do not possess the fastness of colour peculiar to acid dyes1 has a limited application4 ,but by treatment with sulphuric acid magenta is converted into an acid magenta1 and this dye has wider application than the basic salt4 ,similarly the basic dye called aniline blue is insoluble in water1 and therefore has only a limited use1 but by treatment with sulphuric acid it is converted into alkali blue1 soluble blue and so on1 which dissolve readily in water and are good fast colours4 ,the acid dyes generally have a weaker colouring power than the basic dyes1 but they produce very even shades4 ---------------------------------------- -------------------- ,colour4 ,acid4 ,basic4 ,substantive4 ---------------------------------------- -------------------- ,yellow ,metanil yellow4 ,auramine4 ,cotton yellow4 and ,paper yellow4 ,chrysoidine4 ,chrysophenine4 ,orange4 ,orange ,,ii4 ,naphthol yellow ,s4 ,quinoline yellow4 ,red4 ,fast red ,a4 ,rhodamine4 ,congo red4 ,cotton scarlet4 ,paper scarlet4 ,benzopurpurin4 ,erythrine4 ,safranine4 ,oxamine red4 ,ponceau4 ,magenta4 ,blue ,water blue #a ,n4 ,methylene blue4 ,azo blue4 and ,fast blue4 ,victoria blue4 ,violet4 ,acid violet4 ,new blue4 ,indoine blue4 ,methyl violet4 ,crystal violet4 ,brown ,naphthylamine ,bismarck brown4 brown4 ,vesuvine4 ,black ,nigrosine4 ,coal ,black ,b4 ,brilliant black ,b4 ,green ,diamond green4 ,malachite green4 ---------------------------------------- -------------------- ,the difference in the composition of the basic and acid dyes is taken advantage of in the dyeing of paper pulp to secure a complete distribution of the colouring matter upon the pulp1 with the result that the intensity of colour is increased1 its fastness strengthened1 and the process of dyeing generally rendered more economical4 ,this is effected by the judicious addition of a suitable acid dye to the pulp already coloured with the basic dye4 ,the direct colouring matters have but a very limited application for paper dyeing owing to their sensitiveness to acids and alkalies4 ,in the colouring of paper pulp1 attention is given to many important details1 such as3-- ,fading of ,colour4--,some loss of colour almost invariably occurs even with dyes generally looked upon as fast to light4 ,the shade or tint of the paper is affected not only by exposure to light1 but by contact of the coloured paper with common boards on which it is often pasted4 ,the alkalinity of straw boards1 for example1 is frequently one source of serious alteration of colour1 and the acidity of badly made pastes and adhesives another4 ,in all such cases1 the dyes must be carefully selected in order to obtain a coloured paper which will show a minimum alteration in tint by exposure to light or by contact with chemical substances4 ,this is particularly necessary in coloured wrapping paper used for soap1 tea1 cotton yarn1 and similar goods4 ,unevenness of ,colour4--,the different affinity of the various paper-making fibres for dyes is apt to produce an uneven colour in the finished paper4 ,this is very noticeable in mixtures of chemical wood pulp or cellulose and mechanical wood pulp4 ,the ligno-cellulose of the latter has a great affinity for basic dyes1 and if the required amount of dye is added to a beater containing the mixed pulps in an insufficiently diluted form1 the mechanical wood pulp becomes more deeply coloured than the cellulose4 ,if the former is a finely ground pulp1 the effect is not very noticeable1 but if it is coarse1 containing a large number of coarse fibres1 then the paper appears mottled4 ,the defect is still further aggravated when the paper is calendered1 especially if calendered in a damp condition4 ,in that case the strongly coloured fibres of mechanical wood are very prominent4 ,when dyes have been carelessly dissolved and added to the beating engine without being properly strained1 unevenness of colour may often be traced to the presence of undissolved particles of dye4 ,irregular ,colour of the two ,sides4--,many papers exhibit a marked difference in the colour of the two sides4 ,when heavy pigments are employed as the colouring medium1 the under side of the sheet1 that is1 the side of the paper in contact with the machine wire1 is often darker than the top side4 ,the suction of the vacuum boxes is the main cause of this defect1 though the amount of water flowing on to the wire1 the shake of the wire1 and the extent to which the paper is sized are all contributory causes4 ,by careful regulation of these varying conditions the trouble is considerably minimised4 ,the under surface of the paper is not invariably darker than the top surface4 ,with pigments of less specific gravity the reverse is found to be the case4 ,this is probably to be explained by the fact that some of the colouring matter from the under side is drawn away from the paper by the suction boxes1 and the pigment on the top side is not drawn away to any serious extent1 because the layer of pulp below it acts as a filter and promotes a retention of colour on the top side4 ,it is interesting to notice that this irregularity sometimes occurs with soluble dyes1 as for example in the case of auramine4 ,the decomposition of this dye when heated to the temperature of boiling water is well known1 and the contact of a damp sheet of paper coloured by auramine with the surfaces of steam-heated cylinders at a high temperature brings about a partial decomposition of the dye on one side of the paper4 ,generally speaking1 acid dyes are more sensitive to heat than basic dyes4 ,the presence of china clay in a coloured paper is also an explanation of this irregular appearance of the two sides4 ,china clay readily forms an insoluble lake with basic dyes1 and when the suction boxes on the machine are worked with a high vacuum the paper is apt to be more deeply coloured one side than another4 ,the ,machine ,backwater4--,economy in the use of dyes to avoid a loss of the colouring matter in the backwater1 or waste water from the paper machine1 is only obtained by careful attention to details of manufacture on the one hand and by a knowledge of the chemistry of dyeing on the other4 ,the loss is partly avoided by regulating the amount of water used on the machine1 so that very little actually goes to waste1 and further reduced by ensuring as complete a precipitation of the soluble dye as possible4 ,the acid dyes generally do not give a colourless backwater1 and all pulps require to be heavily sized when acid dyes are used4 ,the basic dyes are more readily precipitated than the acid dyes1 particularly if a suitable mordant is used1 even with heavily coloured papers4 ,the addition of an acid dye to pulp first coloured with a basic dye is frequently resorted to as a means of more complete precipitation4 ,dyeing to ,sample4--,the matching of colours has been greatly simplified through the publication of pattern books by the firms who manufacture dyes1 in which books full details as to the composition of the paper1 the proportion of colour and the conditions for maximum effects are fully set out4 ,the precise results obtained by treating paper pulp with definite proportions of a certain dye1 or a mixture of several dyes1 is determined by experimental trials4 ,a definite quantity of moist partially beaten and sized pulp1 containing a known weight of air-dry fibre1 is mixed with a suitable volume of water at a temperature of #hj to #ij ,f4 and the dye-stuff added from a burette in the form of a #a per cent4 solution4 ,if preferred a measured volume of a #a per cent4 solution of the dye can be placed in a mortar1 and the moist pulp1 previously squeezed out by hand1 added gradually and well triturated with the pestle4 ,the dyed mixture is then suitably diluted with water1 made up into small sheets of paper on a hand mould or a siphon mould1 and dried4 ,the effect of small additions of colour to the contents of a beating engine is frequently examined in a rough and ready way by the beaterman1 who pours a small quantity of the diluted pulp on the edge of the machine wire while the machine is running4 ,this gives a little rough sheet of paper very quickly4 ,the comparison of the colour of a beaterfull of pulp with the sample paper which it is desired to match is also effected by reducing a portion of the paper to the condition of pulp1 so that a handful of the latter can be compared with a quantity of pulp from the engine4 ,this is not always a reliable process1 especially with papers coloured by dyes which are sensitive to the heat of the paper machine drying cylinders4 ,detection of ,colours in ,papers4--,the examination of coloured papers for the purpose of determining what dyes have been employed is a difficult task4 ,with white papers which have been merely toned the proportion of dye is exceedingly small1 and a large bulk of paper has to be treated with suitable solvents in order to obtain an extract containing sufficient dye for investigation4 ,with coloured papers dyed by means of pigments1 the colour of the ash left on ignition is some guide to the substance used1 a red ash indicating iron oxide1 a yellow ash chromate of lead1 and so on4 ,with papers dyed by means of coal tar colours the nature of the colouring matter may be determined by the methods of analysis employed for the examination of textile fibres4 ,the following hints given by ,kollmann will be found useful3-- ,tear up small about #ajj grammes of paper1 and boil it in alcohol1 in a flask or a reflux condenser4 ,this must be done before the stripping with water1 so as to extract the size which would otherwise protect the dye from the water4 ,of course the alcohol treatment is omitted with unsized paper4 ,the paper is now boiled with from three to five lots of water1 taking each time only just enough to cover the paper4 ,this is done in the same flask after pouring off any alcohol that may have been used1 and also with the reflux condenser4 ,the watery extract is mixed with the alcohol extract 7if any74 ,three cases may occur3--7#a7 ,the dye is entirely stripped1 or very nearly so4 7#b7 ,the dye is partly stripped1 what remains on the fibres showing the same colour as at first or not4 7#c7 ,the dye is not stripped4 ,to make sure of this the solution is filtered1 as the presence in it of minute fragments of fibre deceive the eye as to the stripping action4 ,in the first two cases the mixed solutions are evaporated down to one half on the water bath1 filtered1 evaporated further1 and then precipitated by saturating it with common salt4 ,the dye is thrown out at once1 or after a time4 ,it may precipitate slowly without any salt4 ,the precipitated dye is filtered off and dried4 ,to see whether it is a single dye or a mixture1 make a not too dark solution of a little of it in water1 and hang up a strip of filter paper so that it is partly immersed in the solution4 ,if the latter contains more than one dye they will usually be absorbed to different heights1 so that the strip will show bands of different colours crossing it4 ,if it is found that there is only one dye1 dissolve some of it in as little water as possible1 and mix it with tannin-reagent1 which is made by dissolving equal weights of tannin and sodium acetate in ten times the weight of either of water4 ,if there is a precipitate there is a basic dye1 if not1 an acid dye4 ,in the former case mix the strong solution of the dye with concentrated hydrochloric acid and zinc dust1 and boil till the colour is destroyed4 ,then neutralise exactly with caustic soda1 filter1 and put a drop of the filtrate on to white filter paper4 ,if the original colour soon reappears on drying1 we draw the following conclusions3-- 7a7 ,the colour is red2 the dye is an oxazine1 thiazine1 azine1 or acridine dye1 e4g41 safranine4 7b7 ,it is orange or yellow2 the dye is as in 7a71 e4g41 phosphine4 7c7 ,it is green2 the dye is as in 7a71 e4g41 azine green4 7d7 ,it is blue2 the dye is as in 7a71 e4g41 ,nile blue1 new blue1 fast blue1 or methylene blue4 7e7 ,it is violet2 the dye is as in 7a71 e4g41 mauveine4 ,if the original colour does not reappear on drying1 but does so if padded with a #a per cent4 solution of chromic acid1 we draw the following conclusions3-- 7a7 ,the colour is red2 the dye is rhodamine or fuchsine1 or one of their allies4 7b7 ,it is green2 the dye is malachite green1 brilliant green1 or one of their allies4 7c7 ,it is blue2 the dye is night blue1 ,victoria blue1 or one of their allies4 7d7 ,it is violet2 the dye is methyl violet1 crystal violet1 or one of their allies4 ,if the original colour does not reappear even with chromic acid1 it was in most cases a yellow or a brown1 referable to auramine1 chrysoidine1 ,bismarck brown1 thioflavine1 or one of their allies4 ,if the tannin reagent produces no precipitate1 reduce with hydrochloric acid and zinc1 or ammonia and zinc1 and neutralise and filter as in the case of a basic dye4 ,the solution when dropped on to white filter paper may be bleached 7a71 may have become a brownish red 7b71 may have been imperfectly and slowly bleached 7c71 or may have undergone no change 7d74 7a7 ,if the colour quickly returns the dye is azurine1 indigo-carmine1 nigrosine1 or one of their allies4 ,if it returns only on padding with a #a per cent4 solution of chromic acid1 warming1 and holding over ammonia1 some of the dye is dissolved in water mixed with concentrated hydrochloric acid1 and shaken up with ether4 ,if the ether takes up the dye1 we have aurine1 eosine1 erythrine1 phloxine1 erythrosine1 or one of their allies4 ,if it does not1 we have acid fuchsine1 acid green1 fast green1 water blue1 patent blue1 or one of their allies4 ,if the colour never returns1 heat some of the dye on platinum foil4 ,if it deflagrates with coloured fumes1 the dye is aurantia1 naphthol yellow ,s41 brilliant yellow1 or one of their allies4 ,if it does not deflagrate1 or very slightly1 dissolve a little of the dye in one hundred times its weight of water1 and dye a cotton skein in it at the boil for about fifteen minutes4 ,then rinse and soap the skein vigorously4 ,if the dyeing is fast with this treatment we have a substantive cotton yellow or thiazine red2 if it is not1 we have an ordinary azo dye4 7b7 ,the dye is an oxyketone1 such as alizarine4 7c7 ,the dye is thiazol yellow1 or one of its allies4 7d7 ,the dye is thioflavine ,s41 quinoline yellow1 or one of their allies4 ,if the dye is not stripped by alcohol and water1 it is either inorganic or an adjective dye1 such as logwood black1 cutch1 fustic1 etc42 and we proceed according to the colour as follows3-- ,if it is red or brown1 the dyed fibre is dried and divided into two parts4 ,one is boiled with bleaching powder4 ,if it is bleached entirely or to a large extent1 the dye is cutch4 ,if the bleach has no action1 incinerate some of the dyed fibre in an iron crucible and heat the ash on charcoal before the blowpipe4 ,if a globule of lead is formed1 we have saturn red4 ,the second portion is boiled with concentrated hydrochloric acid4 ,if there is no action1 we have ,cologne umber2 if there is partial action1 we have real umber2 if the dye dissolves completely to a yellow solution1 we have an ochre2 if the solution is colourless instead of yellow1 and chlorine is evolved during solution1 we have manganese brown4 ,if the colour is yellow or orange1 boil with concentrated hydrochloric acid4 ,if we get a green solution and a white residue1 we infer chrome yellow or orange4 ,if we get a yellow solution1 we boil it with a drop or two of nitric acid and then add some ammonium sulphocyanide4 ,a red colour shows an ochre or ,sienna earth4 ,if the colour is green1 boil with caustic soda lye4 ,if the fibre turns brown1 we have chrome green4 ,if no change takes place1 boil with concentrated hydrochloric acid4 ,a yellow solution shows green earth2 a red colour logwood plus fustic4 ,if the colour is blue or violet1 boil with caustic soda lye4 ,if the fibre turns brown1 we have ,prussian blue4 ,if no change takes place1 boil with concentrated hydrochloric acid4 ,a yellow solution shows smalts4 ,if the colour is destroyed1 and the smell of rotten eggs is developed1 we have ultramarine4 ,if the colour is black1 warm with concentrated hydrochloric acid containing a little tin salt4 ,if the black is unchanged1 we have a black pigment4 ,if we get a pink to deep red solution we have logwood black4 ,by means of the tests above detailed at length the group to which the dye belongs is discovered1 and often the actual dye itself4 ,once the group is known it is generally easy1 by means of the special reactions given in many books1 e4g41 in ,schultz and ,julius's ,tabellarische bersicht1 to identify the particular dye4 ,when one has to deal with a single dye and simply desires to determine its group1 the following table1 due to ,j4 ,herzfeld1 will suffice4 ,originally intended for textiles1 it will serve1 with some modifications here made in it1 for the rapid testing of paper4 #a4--,,red ,,and ,,reddish ,,brown ,,dyes4 ,boil the paper with a mixture of alcohol and sulphate of alumina4 ,if no dye is extracted or a fluorescent solution is formed1 we have an inorganic pigment1 or eosine1 phloxine1 rhodamine1 safranine1 or one of their allies4 ,add bleaching powder solution1 and heat4 ,if the paper is bleached1 add concentrated hydrochloric acid4 ,a violet colour shows safranine or an analogue4 ,if there is no colour1 but the fluorescence disappears1 we have eosine1 phloxine1 rhodamine1 or one of their allies4 ,if the paper is not bleached test for inorganic colouring matters4 ,cutch brown is partly but not entirely bleached4 ,if the alumina solution gives a red or yellow solution without fluorescence1 add to it concentrated sodium bisulphite4 ,if bleaching takes place1 heat a piece of the paper with dilute spirit4 ,a red extract shows sandal wood1 fuchsine1 etc4 ,if there is little or no extract1 we have acid fuchsine or one of its allies4 ,if the bisulphite causes no bleaching1 boil a piece of the paper with very dilute hydrochloric acid4 ,if the colour is unchanged1 heat another piece of the paper with dilute acetate of lead4 ,if no change takes place1 we have an azo dye4 ,if the colour turns to a dark brownish red1 we have cochineal or the like4 ,if the boiling with very dilute hydrochloric acid darkens the colour we have a substantive cotton dye4 #b4--,,yellow ,,and ,,orange ,,dyes4 ,heat some of the paper with a not too dilute solution of tin salt in hydrochloric acid4 ,if the colour is unchanged1 with a colourless or yellow solution1 boil some more paper with milk of lime4 ,a change to reddish or brown shows turmeric or a congener4 ,absence of change shows phosphine1 quinoline yellow1 or a natural dye-stuff4 ,if the acid tin solution turns the paper red1 and then quickly bleaches it to a pale yellow1 we have fast yellow1 orange ,,iv41 metanil yellow1 brilliant yellow1 or the like4 ,if the tin turns the paper greyish1 heat another portion with ammonium sulphide4 ,a blackening shows a lead or iron yellow4 ,if there is no change1 we have naphthol yellow1 auramine1 azoflavine1 orange ,,ii41 chrysoidine1 or one of their allies4 #c4--;,,green ,,dyes4 ,heat a sample of the paper in dilute spirit4 ,if the spirit acquires no colour1 warm for a short time with dilute sulphuric acid4 ,if both paper and solution become brownish red1 we have logwood plus fustic4 ,if this fails1 boil with concentrated hydrochloric acid4 ,a yellow solution shows green earth4 ,if this fails1 boil with concentrated caustic soda4 ,browning shows chrome green4 ,if the spirit becomes blue1 it is a case of paper which has been topped with blue on a yellow1 brown1 or green ground4 ,the solution and the insoluble part are separately tested4 ,the case is probably one of an aniline blue dyed over a mineral pigment4 ,if the spirit becomes green1 heat with dilute hydrochloric acid4 ,if the fibre is completely or nearly bleached1 and the acid turns yellow1 the dye is brilliant green1 malachite green1 or one of their allies4 #d4--;,,blue ,,and ,,violet ,,dyes4 ,heat some of the paper with dilute spirit4 ,if the alcohol remains colourless1 we have ,prussian blue or ultramarine4 ,if it becomes blue or violet1 shake some of the paper with concentrated sulphuric acid4 ,a dirty olive green shows methylene blue1 and a brownish colour shows spirit blue1 water blue1 ,victoria blue1 methyl violet1 etc4 ,if the spirit turns yellow1 and the colour of the paper changes1 we have wood blue or wood violet4 ,,chapter ,,xi ,,paper ,,mill ,,machinery ,in the case of common printings and writings1 which form the great bulk of the paper made1 the possibility of one mill competing against another1 apart from the important factor of the cost of freight1 coal1 and labour1 is almost entirely determined by the economy resulting from the introduction of modern machinery4 ,the equipment of an up-to-date paper mill1 therefore1 comprises all the latest devices for the efficient handling of large quantities of raw material1 the economical production of steam1 and the minimum consumption of coal1 matters which are of course common to most industrial operations1 together with the special machinery peculiar to the manufacture of paper4 ,the amount of material to be handled may be seen from the table on page #bae1 which gives the approximate quantities for the weekly output of a common news and a good printing paper4 ,economy in ,coal ,consumption4--,the reduction to a minimum of the amount of coal required for a ton of paper has been brought about by the use of appliances for the better and more regular combustion of the coal1 such as mechanical stokers1 forced and induced draught1 the introduction of methods for utilising waste heat in flue gases by economisers1 and the waste heat in exhaust steam and condensed water by feed-water heaters1 the adoption of machines for securing the whole energy of the live steam by means of superheaters1 adequate insulation of steam mains and pipes1 high pressure boilers1 and engines of most recent design4 ,the firing of steam boilers is now conducted on scientific principles1 the coal being submitted regularly to proper analysis for calorific value1 the evaporative power of the boilers being determined at intervals by adequate trials1 the condition of the waste flue gases being automatically ,,table ,,showing ,,the ,,materials ,,required ,,for ,,news ,,and ,,printings4 ---------------------------------------- --------------------- -- ,common ,news4 ,good ,printings4 ---------------------------------------- --------------------- ,weekly output of paper1 say #fjj tons #bej tons ,mechanical wood pulp1 moist1 #ej per cent4 dry #hjj ,nil4 ,chemical wood pulp1 dry #bjj #aej tons ,esparto ,nil4 #bjj ,soda ash ,nil4 #af ,coal #fjj tons #hjj ,lime ,nil4 #de ,china clay #fj tons #be ,bleach ,nil4 #cj ,alum1 rosin1 and chemicals #bj tons #bj ,water1 per ton paper #h1jjj gallons #dj1jjj gallons ---------------------------------------- --------------------- ,the ,sarco ,combustion ,recorder4--,this instrument is a device which automatically records the percentage of carbonic acid gas in the waste gases from boiler furnaces4 ,the flue gases are analysed at frequent and regular intervals1 and the results of the analysis can be seen on a chart immediately1 so that it is possible to determine the effect of an alteration in the firing of the boilers within two minutes of its taking place4 ,the apparatus is rather complicated1 but the principle upon which it is based is simple4 ,measured quantities of the flue gases are drawn into graduated glass tubes and brought into contact with strong caustic soda solution1 which absorbs all the carbonic acid gas4 ,the remaining gases not absorbed by the caustic soda are automatically measured and the percentage of carbonic acid gas registered on the chart4 ,the use of suitable boiler feed-water is also an important factor in modern steam-raising plant4 ,the hot condensed water from the paper machine drying cylinders1 and exhaust steam from the engines and steam-pipes1 is returned to the stoke-hole to be utilised in heating up the cold water which has been previously softened by chemical treatment4 ,illustration3 ,,fig4 #ee4--;,conventional ,diagram of a ,water ,softening ,plant4 ,a4 ,water supply4 ,b4 ,regulating tank4 ,c4 ,lime mixer4 ,d4 ,soda tank4 ,e4 ,settling tank and filter4 ,f4 ,outlet for softened water4 ,water ,softening4--,the water softeners available on the market are numerous1 and as each possesses special advantages of its own1 it would be almost invidious to select any one for particular notice4 ,they are based upon the principle of mixing chemicals with the water to be treated1 so as to precipitate the matters in solution and give a boiler feed-water free from carbonates and sulphates of lime and magnesia4 ,the chemicals are added in the form of solutions of carefully regulated strength to the water1 which flow in a continuous stream into a tank4 ,the flow of the water and chemical reagent is adjusted by previous analysis4 ,the various machines differ in details of construction1 and in the methods by which the mixing of the water and reagents is effected4 ,the object to be achieved is the complete precipitation of the dissolved salts and the production of a clear water1 free from sediment1 in an apparatus that will treat a maximum quantity of water at a cheap rate per #a1jjj gallons4 ,the process needs proper attention4 ,the addition of reagents in wrong proportions will do more harm than good1 and possibly result in hardening the water instead of softening it4 ,the following may be quoted as an example3-- ---------------------------------------- ---------------- ,composition of ,water4 ,before ,after ,change4 ,treatment4 ,treatment4 ---------------------------------------- ---------------- ,calcium carbonate #achfc #chibj #bejeg gain ,calcium oxide 7lime7 #jj #adcjj #adcjj ,calcium silicate #bjfb #ceia #aebi ,calcium sulphate #afbe #baba #jdif ,magnesia #jj #jbff #jbff ,ferric oxide1 etc4 #jddg #jihg #jedj ---------------------------------- ,scale forming mineral #agiig #fjahe #dbahh gain ---------------------------------- ,calcium chloride #acca #baad #jghc gain ,magnesium chloride #jfgb #jj #jfgb loss ,sodium chloride #jdgh #jdgf #jjjc ---------------------------------- ,soluble salts #bdhb #beij #jajh gain ---------------------------------- ,total mineral matter #bjdgi #fbggf #dbbig gain ---------------------------------- ,carbonic acid gas #iga #jj #iga loss ,oxygen gas #jff #jff #jj ---------------------------------------- ---------------- ,treatment required3 #ah lbs4 of lime1 #jb lbs4 soda ash per #a1jjj gallons4 ,apparently #ee lbs4 of lime were being used and no soda 7,stromeyer74 ,superheated ,steam4--,the effective application of the energy of the high pressure steam is probably one of the most important problems in paper mill economy4 ,the use of superheated steam is being extended in every direction1 and1 in addition to the advantages obtained in the steam engine itself1 its wider possibilities for the boiling of esparto1 wood1 and fibres generally have been noted4 ,the following case may be quoted as the result of a trial at a paper mill1 showing for stated conditions the advantages of superheated steam3-- ---------------------------------------- --------- -- ,superheated ,ordinary ,steam4 ,steam4 ---------------------------------------- --------- ,duration of test hours #bf #cd ,coal consumed 7lbs47-- ,per hour #faje #ffae ,per #a h4-p4 hour #ahc #bjh ,water evaporated 7lbs47-- ,per hour #d1hcb #e1fgi ,per #a h4-p4 hour #adee #agh ,from and at #bab ,f4 #hg #hid ,steam1 temperature ,f4 #dfd #ccd ,pressure #ijc #ijh ,steam engine-- #a h4-p4 total #ccae #cbcb ,temperature ,f4 #chah #ccch ,coal used per #a h4-p4-- ,per hour at boiler #ahc #bjh ---------------------------------------- --------- ,this appears to show a saving of #ab per cent4 ,gas ,producers4--,the substitution of gas for steam in the paper mill has not yet proved a success4 ,the fact that heat is required for the drying cylinders of a paper machine1 and that the heat is most cheaply and readily obtained in the form of exhaust steam from the engines driving the paper machine1 militates considerably against economies which might otherwise be possible4 ,the difficulties of heating such cylinders1 or rather of properly controlling and regulating the temperature by any other means than steam1 may easily be surmised4 ,gas engines of over #bjj h4-p4 seem to give considerable trouble at present1 but no doubt in course of time the required improvements will be effected4 ,it is generally supposed that gas producers can only be economical when utilised for the production of gas on a large scale1 and for distribution to engines of smaller capacity than the main steam engine required in a paper mill4 ,the peculiar conditions of the manufacture of paper do not appear to be favourable to the adoption of the gas producer system in its present form4 ,motive ,power4--,the paper-maker has taken advantage of every modern improvement in steam engines for the purpose of reducing the cost of motive power4 ,amongst other alterations in this direction the use of a high speed enclosed engine and the employment of the modern steam turbine may be noted4 ,in the enclosed engine the working parts are boxed in by a casing fitted with oil-tight doors4 ,the cranks and connecting rods splash into the oil1 which is thus thrown about in all directions1 so as to ensure sufficient lubrication4 ,another feature of this engine is the variable speed1 and it is possible to run the paper machine at speeds varying from #ajj to #ejj ft4 per minute without the use of change wheels4 ,electrical ,driving4--,the application of electricity for motive power has made steady advances in the paper mill4 ,at first it was limited to the driving of machinery in which variations of speed or load were not required to any large extent1 but of recent years beating engines1 calenders1 and paper machines have all been fitted with electrical drives4 ,illustration3 ,,fig4 #ef4--;,an enclosed ,steam ,engine4 ,the following details relate to the installation at the ,linwood ,paper ,mills3-- ,the installation consists of #bej-,k4,w4 steam dynamos4 ,the engines are ,willan's high speed triple expansion1 working with a boiler pressure of #bej lbs4 per square inch at the stop valve1 the steam being superheated to give a temperature of #ejj ,fahr4 at the engine4 ,by means of jet condensers a vacuum of #be to #be inches is obtained on the engines4 ,the two boilers are of the ,babcock type1 and have #c1ehj square feet of heating surface each4 ,the furnaces have chain grate stokers1 and the boilers are arranged with their own superheaters4 ,the motor equipment consists of eight #hj1 two #ej1 and ten #be ,b4,h4,p4 motors4 ,six of the #hj ,b4,h4,p4 drive the beating engines1 and it has been found that the motors readily respond to an overload of #ej per cent4 without beating or other trouble4 ,to remedy the excessive and sudden variation a belt drive was adopted4 ,an #hj motor drives the pulp refining engine4 ,the two paper-making machines have each two motors1 one a #be and a #ej and the other two #be ,b4,h4,p4 motors4 ,the speed can be regulated with exactitude4 ,the auxiliary plant of the paper-making machine1 pumps1 agitators1 etc41 is worked from lines of shafting driven by motors4 ,calender motors are of the variable speed type1 being designed to run from #ajj revolutions per minute to #fjj revolutions per minute4 ,variations from #cjj to #fjj revolutions per minute can be regulated by the shunts1 the loss being negligible4 ,several of the motors are geared up to the various machines1 as is the case with the calender4 ,as regards cost1 the capital outlay on the #ejj-,k4,w4 generating plant1 including engines1 dynamos1 boilers1 condensers1 steam pipes1 filters1 etc41 and all engine room accessories1 was #i1ejj4 ,illustration3 ,,fig4 #eg4--;,an ,electrically ,driven ,paper ,machine4 ,in addition to the above1 the plant also contains a ,parson's steam turbine of #a1jjj ,k4,w41 driving two continuous current dynamos4 ,illustration3 ,,fig4 #eh4--;,diagram of the ,eibel ,process4 ,the ,eibel ,patent4--,one of the most important improvements in connection with the manufacture of newspaper is the ,eibel process1 designed to increase the speed of the machine and to reduce the amount of suction at the vacuum box4 ,in the ordinary machine the wire has usually been arranged to move in a horizontal plane4 ,in some machines means have been provided for adjusting the breast-roll end of the wire to different elevations to provide for dealing with different grades of stock1 but the wire has never hitherto been so inclined as to cause the paper stock to travel at a speed1 under the action of gravity1 to equal or approximate the speed of the wire4 ,in all previous methods of working1 the wire has for a considerable portion of its length1 starting from the breast-roll1 drawn the stock along in consequence of the wire moving much faster than the stock1 and the stock has waved1 or rippled1 badly near the breast-roll end of the wire4 ,this has gradually diminished until an equilibrium has been established and an even surface obtained1 but not until the waving or rippling has ceased at some considerable distance from the breast-roll have the fibres become laid uniformly1 and the machines have therefore necessarily been run slowly to give ample time for the water to escape and for the fibres to lie down so as to make them a uniform sheet4 ,in many cases the breast-roll has been raised #ad or #ae inches1 and the stock rushes1 as it were1 downhill4 ,as1 during the formation of the paper1 the stock and the wire practically do not move relatively to each other1 there is no drag of the stock upon the wire2 consequently there is a more rapid and uniform drainage of the water from the stock1 the full influence of the shake is made effective to secure uniformity in the distribution and interlocking of the fibres1 and the regularity of the formation of the paper is not disturbed by waves or currents1 which would otherwise be caused by pull of the wire upon the stock4 ,this ingenious device is now working successfully in many paper mills4 ,machinery4--,in setting out the plant necessary for a paper mill which is designed to produce a given quantity of finished paper1 the manufacturer takes into consideration the class of paper to be made and the raw material to be employed4 ,the following schedule has been prepared on such a basis3-- ,,plant ,,and ,,machinery ,,for ,,high-,,class ,,printings4 ,paper4 ,high-class printings made of wood pulp and esparto1 used alone or blended in varying proportions as required4 ,quantity1 #bej tons weekly4 ,raw ,material4 ,esparto2 chemical wood pulp4 ,quantity3 esparto1 about #bjj tons2 wood pulp1 #aej to #afj4 ,china clay and usual chemicals4 ,in the estimation of materials required for the production of about #bej tons of paper1 it is assumed that the #bjj tons of esparto fibre will yield #ij tons bleached esparto fibre1 and that the mechanical losses which take place during manufacture are counterbalanced by the weight of china clay added to the pulp4 ,these conditions naturally vary in different mills1 but such variations do not affect the schedule of machinery4 ,unloading ,sheds4 #b steam or electric cranes for handling fibre1 clay1 alum1 bleach1 rosin1 coal1 and finished paper4 #a #c-ton weighbridge4 #a #e-;cwt4 platform scales4 ,steam ,plant4 #f #h-;ft4 by #cj-;ft4 ,lancashire boilers4 ,fuel economiser4 ,feed-water pump and tank4 ,water softening apparatus4 #a #ejj-;h4-p4 main steam engine1 for fibre departments and beater floor4 ,chemical ,department4 ,hoist for clay1 alum1 bleach1 lime1 c4 #d causticising pans1 #i ft4 diameter1 #i ft4 deep4 #b storage tanks4 #b chalk sludge filter presses4 #b clay-mixing vats1 #f ft4 diameter1 #f ft4 deep4 #a starch mixer1 #f ft4 diameter1 #f ft4 deep4 #a size boiler1 #h ft4 diameter1 #h ft4 deep4 #c size storage tanks1 #a1jjj gallons each4 #c bleach-mixing vats4 #c bleach liquor settling tanks4 #b clear bleach liquor storage tanks4 #a alum dissolving tank4 ,recovery ,department3-- ,soda4 #a multiple effect evaporating plant4 #a rotary furnace4 #d lixiviating tanks1 #b1jjj gallons each4 #b storage tanks for clear liquor from lixiviating tanks1 #bj1jjj gallons capacity4 ,fibre4 #b tanks for receiving machine backwater4 #b ,fullner's stuff catchers1 or some other system of treating backwater4 #b filter presses4 ,esparto ,department4 #a esparto duster4 ,travelling conveyer for cleaned esparto4 #f ,sinclair vomiting boilers1 each of #c tons capacity4 #b measuring tanks for caustic liquor4 #d washing engines1 #ae cwt4 capacity4 #f ,tower bleaching engines4 #a presse-pte4 #aj galvanised iron trucks4 ,wood ,pulp ,department4 #d pulp disintegrators and pumps4 #d ,tower bleaching engines4 #d washing tanks or drainers4 #f galvanised iron trucks4 ,beater ,floor4 #h #a1bjj-lbs4 beating engines4 #b ,marshall refiners4 #f galvanised iron trucks4 ,paper ,machine ,room4 #b paper machines1 #ajf in4 wide1 with stuff chests1 strainers1 and engines complete4 #a paper machine1 #abj in4 wide1 with stuff chests1 strainers1 and engines complete4 ,patent dampers for each machine4 ,calendering ,room4 #b #aaj-;in4 supercalenders4 #b #ajj-;in4 supercalenders4 #b #f-reel cutters4 #a #bjj-;h4-p4 main steam engine4 ,finishing ,room4 ,sorting tables4 ,packing press4 ,weighing machine4 ,repairs ,department4 ,usual repair outfit1 such as lathes1 planing machine1 drilling tools1 etc4 ,blacksmith's shop outfit4 ,carpenter's shop outfit4 ,calender roll grinder4 ,water ,supply4 ,main storage tank1 #ej1jjj gallons capacity4 ,water pumps4 ,piping and connections to various departments4 ,bell's patent filters 7if necessary74 ,,chapter ,,xii ,,the ,,deterioration ,,of ,,paper ,recent complaints about the quality of paper and the rapid decay of manuscripts and papers have resulted in arousing some interest in the subject of the durability of paper used for books and legal documents1 and in the equally important question of the ink employed4 ,the ,society of ,arts and the ,library ,association in ,england and the ,imperial ,paper ,testing ,institute in ,germany have already appointed special committees of inquiry1 and from this it is evident that the subject is one of urgent importance4 ,it is sometimes argued that the lack of durability is due to the want of care on the part of manufacturers in preserving the knowledge of paper-making as handed down by the early pioneers1 but such an argument is superficial and utterly erroneous4 ,the quality of paper1 in common with the quality of many other articles of commerce1 has suffered because the demand for a really good high-class material is so small4 ,the general public has become accustomed to ask for something cheap1 and since the reduction in price is only rendered possible by the use of cheap raw material and less expensive methods of manufacture1 the paper of the present day1 with certain exceptions1 is inferior to that of fifty years ago4 ,the causes which favour the deterioration of paper are best understood by an inquiry into the nature of the fibres and other materials used and the methods of manufacture employed4 ,the ,fibres ,used4--,cotton and linen rags stand preeminent amongst vegetable fibres as being the most suitable for the production of high-class paper capable of withstanding the ravages of time4 ,this arises from the fact that cotton and linen require the least amount of chemical treatment to convert them into paper pulp1 since they are almost pure cellulose1 cotton containing #ihg per cent4 of air-dry cellulose1 and flax #ijf per cent4 ,the processes through which the raw cotton and flax are passed for the manufacture of textile goods are of the simplest character1 and the rags themselves can be converted into paper without chemical treatment if necessary4 ,as a matter of fact certain papers1 such as the ,o4 ,w4 ,s4 and other drawing papers1 are manufactured from rags without the aid of caustic soda1 bleach1 or chemicals4 ,the rags are carefully selected1 boiled for a long time in plain water1 broken up and beaten into pulp1 and made up into sheets by purely mechanical methods4 ,the liability of papers to decay1 in respect of the fibrous composition1 is almost in direct proportion to the severity of the chemical treatment necessary to convert the raw material into cellulose1 and the extent of the deviation of the fibre from pure cellulose is a measure of the degradation which is to be expected4 ,the behaviour of the fibres towards caustic soda or any similar hydrolytic agent serves to distinguish the fibres of maximum durability from those of lesser resistance4 ,it may be noted that in the former the raw materials1 viz41 cotton1 linen1 hemp1 ramie1 etc41 contain a high percentage of pure cellulose1 while in the latter the percentage of cellulose is very much lower1 such fibres as esparto1 straw1 wood1 bamboo1 etc41 giving only #dj-ej per cent4 of cellulose4 ,the two extremes are represented by pure cotton rag and mechanical wood pulp4 ,other things being equal1 the decay which may take place in papers containing the fibre only1 without the admixture of size or chemicals1 may be considered as one of oxidation1 which takes place slowly in cotton1 and much more rapidly with mechanical wood pulp4 ,experimental evidence of this oxidation is afforded when thin sheets of paper made from these materials are exposed to a temperature of #ajj to #aaj ,c4 in an air oven4 ,the cotton paper is but little affected1 while the mechanical wood pulp paper soon falls to pieces4 ,the order of durability of various papers in relation to the fibrous constituents may be expressed thus3 7#a7 rag cellulose2 7#b7 chemical wood cellulose2 7#c7 esparto1 straw1 and bamboo celluloses2 7#d7 mechanical wood pulp4 ,the rate and extent of oxidation is approximately shown by the effect of heat as described4 ,the differences between the celluloses are also shown by heating strips of various papers in a weak solution of aniline sulphate1 which has no effect on wood or rag cellulose1 dyes esparto and straw a pinkish colour1 and imparts a strong yellow colour to mechanical wood pulp and jute4 ,physical ,qualities4--,the permanence of a paper depends not only upon the purity of the fibrous constituents and the freedom from chemicals likely to bring about deterioration1 but also upon the general physical properties of the paper itself4 ,other things being equal1 the more resistant a paper is to rough usage the longer will it last4 ,the reason why rag papers are so permanent is that not only is the chemical condition of the cellulose of the highest order1 but the physical structure of the fibre is such that the strength of the finished paper is also a maximum4 ,the methods of manufacture may be modified to almost any extent1 giving on the one hand a paper of extraordinary toughness1 or on the other hand a paper which falls to pieces after a very short time4 ,thus a strong bank-note paper may be crumpled up between the fingers three or four hundred times without tearing1 while an imitation art paper is broken up when crumpled three or four times4 ,a thorough study of the physical qualities of a paper is therefore necessary to an appreciation of the conditions for durability4 ,the physical structure of the fibre1 the modifications produced in it by beating1 the effect of drying1 sizing1 and glazing upon the strength and elasticity of the finished paper1 are some of the factors which need to be considered4 ,strength4--,the strength of a paper as measured by the tensile strain required to fracture a strip of given width1 and the percentage of elongation which the paper undergoes when submitted to tension1 are properties of the utmost importance4 ,the elasticity1 that is1 the amount of stretch under tension1 has not received the attention from paper-makers that it deserves4 ,if two papers of equal tensile strength differ in elasticity1 it may be taken for granted that the paper showing a greater percentage of elongation under tension is the better of the two4 ,the strength of a paper1 as already indicated1 is greatly influenced by the conditions of manufacture4 ,this has been explained in the chapter devoted to the subject of beating1 and other examples are briefly given in the following paragraphs4 ,bulk4--,the manufacture during recent years of light bulky papers for book production has accentuated the problem in a marked degree1 and the factor of bulk as one of the causes of deterioration is therefore a comparatively new one4 ,it is interesting to notice that the rapid destruction of such books by frequent use is in no way related to the chemical purity of the cellulose of which it is composed1 or to the influence of any chemical substance associated with the fibre4 ,it is purely a mechanical question1 to be explained by reference to the process of manufacture4 ,this paper is made from esparto entirely1 or from a mixture of esparto and wood pulp4 ,the pulp is beaten quickly1 and for as short a time as possible1 little or no china clay being added1 and only a very small percentage of rosin size4 ,the wet sheet of paper is submitted to very light pressure at the press rolls1 and the bulky nature is preserved by omitting the ordinary methods of calendering4 ,the paper thus produced consists of fibres which are but little felted together4 ,the physical condition and structure of the paper are readily noticeable to the eye1 and when these peculiarities are reduced to numerical terms the effect of the conditions of manufacture is strikingly displayed4 ,the effect of this special treatment is best seen by contrasting the bulky esparto featherweight paper with the normal magazine paper made from esparto4 ,in the latter case a smoother1 heavier1 stronger sheet of paper is made from identically the same raw material4 ,but the pulp is beaten for a longer period1 while mineral matter and size are added in suitable proportions4 ,the press rolls and calenders are used to the fullest extent4 ,the difference between these two papers1 both consisting1 as they do1 of pure esparto with a small proportion of ash may be emphasised by comparing the analysis by weight with analysis by volume4 ,the two papers in question when analysed by weight proved to have the following composition3-- ---------------------------------------- ---- ,parts by ,weight4 ---------------------------- -- ,featherweight4 ,ordinary4 ---------------------------------------- -- ,esparto fibre #ifj #ied ,ash1 etc #dj #df ----- ----- #ajjj #ajjj ---------------------------------------- -- ,but if the papers are compared in terms of the composition by volume1 it will be found that the featherweight contains a large amount of air space4 ---------------------------------------- --- ,composition by ,volume4 ---------------------------- -- ,featherweight4 ,ordinary4 ---------------------------------------- -- ,esparto fibre #bhj #fee ,ash1 etc #jg #ah ,air space #gac #cbg ----- ----- #ajjj #ajjj ---------------------------------------- -- ,in other words1 the conditions of manufacture for the bulky paper are such that the fibres are as far apart from one another as possible1 and the cohesion of fibre to fibre is reduced to a minimum4 ,while paper of this description is agreeable to the printer1 and probably to the general reading public1 yet its strength and physical qualities1 from the point of view of resistance to wear and tear1 are of the lowest order4 ,it is very difficult to rebind books made from it1 which is not altogether to be wondered at1 seeing that the bookbinder's stitches can hardly be expected to hold together sheets containing #fj to #gj per cent4 of air space4 ,this concrete case emphasises the necessity for including in a schedule of standards of quality a classification of papers according to strength and bulk4 ,surface4--,the introduction of new methods of printing has brought about some changes in the process of glazing and finishing paper which are not altogether favourable to the manufacture of a sheet having maximum qualities of strength and elasticity1 two conditions which are essential to permanence4 ,in other words1 the very high finish and surface imparted to paper by plate-glazing1 supercalendering1 water finish1 and other devices of a similar character is carried to excess4 ,all papers are improved in strength by glazing up to a certain point1 but over-glazing crushes the paper1 renders it brittle and liable to crack4 ,unfortunately1 the maximum strength of a paper is generally reached before the maximum of finish1 with the result that the former is frequently sacrificed to the latter4 ,the usual result of glazing is found in an increase of #h to #aj per cent4 in the tensile strength1 but a diminution of elasticity to the extent of #h to #aj per cent4 ,with supercalendered magazine papers1 the high surface is imparted for the sake of the illustrations which are produced by methods requiring it4 ,the addition of considerable quantities of clay or mineral substances improves the finish1 so that the question of the relation of glazing to strength1 surface1 and loading is one which affects the subject of deterioration of paper very materially4 ,with writing paper the false standard of an attractive appearance is almost universally accepted by the public as the basis of purchase without any reference to actual quality4 ,mineral ,substances4--,china clay1 sulphate of lime1 agalite and other inert mineral substances are important factors in lowering the quality of paper1 not so much in promoting the actual deterioration of paper by any chemical reaction with the fibres1 as in making the paper less capable of resistance to the influence of atmospheric conditions and ordinary usage4 ,clay in small1 well-defined quantities serves a useful purpose1 if added to some papers1 because it favours the production of a smooth surface1 but when the combination of mineral substances is carried to an extreme1 then the result from the point of view of permanence is disastrous4 ,this is well recognised by all paper-makers1 and in ,germany the limits of the amount of clay or loading in high-grade paper have been rigidly fixed4 ,in the case of imitation art paper1 which contains #be to #cj per cent4 of its weight of clay1 the strength and resistance of the sheet is reduced to a minimum4 ,the paper falls to pieces if slightly damped1 the felting power of the fibres being rendered of no effect owing to the weakening influence of excessive mineral matter4 ,this paper is used chiefly for catalogues1 programmes1 circulars1 and printed matter of a temporary and evanescent character1 and so long as it is confined to such objects it serves a useful purpose1 being cheap1 and suitable for the production of illustrations by means of the half-tone process2 but its lasting qualities are of the lowest order4 ,the addition of #aj per cent4 of any mineral substance must be regarded as the maximum allowance for papers intended for permanent and frequent use4 ,coating ,material4--,the ingenious method for producing an absolutely even surface on paper by the use of a mixture of clay or other mineral substance and an adhesive like glue or casein brushed on to the surface of the paper1 is responsible for many of the complaints about the papers of the present day4 ,the sole merit of this substance is the facility with which half-tone process blocks can be utilised for the purpose of picture production4 ,beyond this1 nothing can be said4 ,the paper is brittle1 susceptible to the least suspicion of dampness1 with a high polish which in artificial light produces fatigue of the reader's eye very quickly1 heavy to handle1 and liable to fall to pieces when bound up in book form4 ,as the fibrous material is completely covered by mineral substances1 it is frequently considered of secondary importance1 with the result that the value of the paper is judged entirely by the surface coating1 with little regard to the nature of the body paper4 ,in such cases1 with an inferior body paper1 the pages of a book very quickly discolour1 and the letterpress becomes blurred4 ,,analysis ,,of ,a ,,typical ,,art ,,paper4 ---------------------------------------- --- ,per ,cent4 ,volume -- by -- ,composition ,weight4 per ,cent4 ---------------------------------------- --- ,fibre #gge ,fibre #fhc ,ash1 etc4 #bbe ,ash #abj ,air space #aig ----- ----- #ajjj #ajjj ---------------------------------------- --- ,rosin4--,the presence of an excess of rosin is a well-known factor in the disintegration of the paper1 even when the fibrous composition is of the highest order4 ,the decomposition is largely due to the action of light1 many experiments having been made by ,herzberg and others to determine the nature of the reactions taking place4 ,one of the chief alterations is the change brought about in the ink-resisting qualities of the paper4 ,the actual character of the chemical reactions as far as the effect on the fibre is concerned is not accurately known4 ,the degradation of a hard-sized rosin paper by exposure to strong sunlight1 for example1 is probably due to the alteration in the rosin size1 and not to any material change in the cellulose4 ,it is hardly conceivable that in a pure rag paper sized with rosin and yielding readily to ink penetration1 after about one year's exposure to light1 the cellulose itself had undergone any chemical changes capable of detection4 ,gelatine4--,papers properly sized with gelatine are preferable to those sized with rosin for the majority of books and documents preserved under normal circumstances4 ,but the nature of a tub-sized paper may be1 and often is1 greatly altered by unusual climatic conditions4 ,in hot1 damp countries papers are quickly ruined1 and high-class drawing papers sized with gelatine often rendered useless4 ,the change is scarcely visible on the clean paper1 and is only observed when the paper is used for water-colour work1 the colour appearing blotchy in various parts of the sheet where the gelatine has been decomposed by the united action of heat and damp4 ,the artist is frequently compelled in such cases to put a layer of heavy white colour on the sheet of paper before proceeding to paint the picture4 ,the storage of books under favourable conditions has a great deal to do with the permanence of the paper1 and the degradation of a paper in relation to the tub-sizing qualities is much hastened by the presence of moisture in the air4 ,starch4--,the same is true of starch1 which is largely employed as a binding or sizing material in paper4 ,the degradation of gelatine1 starch1 and similar nitrogenous substances is due to the action of organisms1 and the following experiments1 suggested by ,cross1 are interesting in this connection4 ,if strips of paper are put into stoppered bottles with a small quantity of warm water and kept at a temperature of about #hj ,f41 fungus growths will be noticed on some of them after the lapse of fourteen days4 ,rag papers sized with gelatine will show micro-organisms of all kinds4 ,a pure cellulose paper1 like filter paper1 will not produce any such effects4 ,the result in the first case is due to the nitrogenous substance1 viz41 the gelatine used in sizing1 since the two papers are identical as far as the cellulose fibres are concerned4 ,high-class wood pulp papers1 unless sized with gelatine1 would not show similar results4 ,the action of the organisms upon the nitrogenous material by a process of hydrolysis is in the direction of the production of soluble compounds allied to the starch sugars capable of being assimilated by organisms4 ,the cellulose of esparto and straw are readily attacked1 and it is on this account that the tissues of the various straws are digested more or less when eaten by animals4 ,it is for this reason that the celluloses from straw and esparto are inferior to the cotton cellulose in producing a paper likely to be permanent4 ,chemical ,residues4--,the necessity for manufacturing a pure cellulose half-stuff is fully recognised by paper-makers4 ,this was not the case in the early days of the manufacture of wood pulp1 for it is a matter of common experience that many of the books printed on wood pulp paper between #ahgj and #ahhj are in a hopeless condition1 and it is quite easy to find books and periodicals of that date the pages of which crumble to dust when handled4 ,this serious defect has been proved to be due to the presence of traces of chemicals used in manufacture which have not been thoroughly removed from the pulp4 ,the precautions necessary in bleaching pulp by means of chloride of lime1 in order to prevent 7#a7 any action between the fibre and the calcium hypochlorite1 7#b7 the presence of residual chlorine or soluble compounds derived from it1 and 7#c7 the presence of by-products arising from the use of an antichlor1 are also well known to paper-makers4 ,the subject has been closely studied by chemists1 who have shown that the deterioration of many modern papers may be ascribed to carelessness in bleaching4 ,the questions relating to the chemical residues of paper can only be adequately dealt with by a discussion of actual cases which arise from time to time4 ,there are certain conditions in manufacture1 common to all papers1 which may give rise to the presence of chemical residues1 of which two have already been mentioned4 ,the acidity of papers is frequently quoted as an instance4 ,it is true that the presence of free acid in a paper is most undesirable1 as it seriously attacks the cellulose1 converting it into an oxidised form4 ,this in course of time renders the paper so brittle as to destroy its fibrous character4 ,the change is brought about by the acid1 which itself suffers no material alteration1 so that the process of deterioration is continued almost indefinitely until the cellulose is completely oxidised4 ,most papers1 however1 show an acid reaction when tested with litmus1 the usual reagent employed by those not familiar with the proper methods of testing paper4 ,all papers which have been treated with an excess of alum for sizing purposes would show an acid reaction with litmus without necessarily containing any free acid4 ,the presence of iron is undesirable1 particularly in photographic papers1 and since cellulose has a remarkable affinity for iron1 the conditions of manufacture which tend to leave iron in the pulp have to be taken into consideration4 ,the presence of minute quantities of iron in the form of impurities must not be confused with the presence of iron in large quantities derived from the toning and colouring of paper by means of iron salts4 ,the fading of colour is frequently observed when coloured papers are tested on boxboards1 particularly those made of straw4 ,this fading may often be traced to the presence of alkali in the straw board which has not been completely removed in the process of manufacture4 ,the blurring of letterpress is a defect which often occurs with printing papers made of chemical wood pulp4 ,the oil in the ink seems to separate out on either side of the letter1 producing a discoloration4 ,in such cases the paper itself frequently exhibits an unpleasant smell4 ,these defects are usually determined by the presence of traces of sulphur compounds in the paper resulting from incomplete washing of the pulp in manufacture4 ,the presence of sulphur compounds sometimes associates itself with papers which have been coloured by means of ultramarine1 which in presence of alum is slightly decomposed by the heat of the drying cylinders4 ,some knowledge of the effect of chemical residues in paper is important1 not only in regard to the deterioration which takes place in the fibre itself1 but also in relation to the fading of the ink which is used4 ,the subject of the ink has received much attention from chemists on account of the serious difficulties which have been experienced by ,state departments in various countries4 ,the ,united ,states ,department of ,agriculture have devised certain methods for ascertaining the suitability of stamping ink used by the ,government and suggest the qualities desirable in such an ink4 ,the ink1 first of all1 must produce an indelible cancellation2 that is1 it must be relatively indelible as compared with the ink used for printing the postage stamps4 ,the post-mark made with the ink must dry quickly in order that the mail matter may be handled immediately without any blurring or smearing of the post-mark4 ,both this property and the property of the indelibility involve the question of the rate at which the ink penetrates or is absorbed by the fibre of the paper4 ,a satisfactory ink does not harden or form a crust on the ink-pad on exposure to air4 ,there must be no deposition of solid matter on the bottom of the vessel in which the ink is stored1 and the pigments on which the indelibility of the ink depends1 if insoluble1 must not settle out in such a way as to make it possible to pour off from the top of the container a portion of the ink which contains little or none of the insoluble pigment or pigments4 ,colour4--,if the subject of deterioration of paper is to be considered in its broadest sense as including changes of any kind1 the fading of colour must be taken into account4 ,the use of aniline dyes which are not fast to light results in a loss of colour in paper just as with textiles1 and the fading may be regarded as a function of the dye and not as arising from its combination with the paper4 ,the gradual fading of some dyes1 however1 and of many water-colour pigments may be traced to the presence of residual chemicals in the paper and to the presence of moisture in an atmosphere impregnated with gaseous or suspended impurities4 ,in fact the latter is a greater enemy to permanence of colour than light1 since it has been proved by experiment that most colours do not fade when exposed to light in a vacuum4 ,the oxygen of the air in combination with the moisture present is the principal agent in bringing about such changes4 ,the dulling of bronze1 or imitation gold leaf1 on cover papers is a practical illustration of this1 though this can hardly be quoted as an instance of actual deterioration of the paper4 ,the maintenance of the original colour can only be assured by the careful selection of pure fibrous material1 the use of fast dyes1 and the preservation of the book or painting from the conditions which favour the fading as described above4 ,for common papers such precautions become impossible1 but for water-colour drawings and valuable papers they are essential4 ,the demand for an abnormally white paper is indirectly the cause of deterioration in colour1 but in this case the ultimate effect is not a fading but a discoloration of white to a more or less distinct yellow or brown colour1 due to changes in the fibre which may often be traced to excessive bleaching4 ,in this case the fading of colour is directly due to deterioration of the paper itself1 and may occur in celluloses of the best type4 ,with lower-grade papers containing mechanical wood pulp the degradation of colour and fibre is inevitable4 ,air and ,moisture4--,the exact effects produced on paper freely exposed1 or in books as ordinarily stored1 depend upon the condition of the atmosphere4 ,pure air has little or no action upon paper1 cellulose being a remarkably inert substance1 and even in impure mechanical wood pulp1 if merely exposed to pure dry air1 the signs of decay would be delayed considerably4 ,the combined action of air and moisture is of a more vigorous character in promoting oxidation changes in the fibres1 or a dissociation of the sizing and other chemical ingredients of the paper4 ,the presence of moisture is1 indeed1 absolutely essential for the reaction of some substances upon one another1 and it is easy to show that certain chemical compounds can be left in ultimate contact1 if absolutely dry1 for a lengthened period without reacting1 but the addition of a little moisture at once produces chemical union4 ,this may be shown by a simple experiment4 ,thus a piece of coloured paper which may be bleached immediately if suspended in an atmosphere of ordinary chlorine gas will remain unbleached for several hours if first thoroughly dried in an oven and exposed to dry gas4 ,in the case of books and papers1 these conditions which promote slow disintegration are aggravated by the presence of impurities in the air1 such as the vapours of burning gas1 the traces of acidity in the atmosphere of large manufacturing towns1 the excessive dampness and perhaps heat of a climate favouring the growth of organisms4 ,all these factors are of varying degrees in different places1 so that the deterioration of papers does not proceed in the same measure and at the same rate everywhere4 ,moisture4--,it may not be out of place to discuss some important relations between moisture and the physical qualities of a sheet of paper4 ,a paper in its normal condition always contains a certain proportion of water as one of its ingredients1 and the presence of this moisture has much to do with the strength1 elasticity1 and use of the paper1 the absence of moisture giving rise to defects and troubles in the use of the paper which to a certain extent lower its commercial value and deteriorate it1 though not perhaps in the sense of permanent degradation of quality4 ,one trouble frequently experienced by stationers and others is that known as wavy edges4 ,the edges of a stack containing sheets of paper piled upon one another frequently twist and curl1 producing what are known as wavy edges4 ,this arises from the fact that the paper when manufactured was deficient in natural moisture1 and that when stacked it has gradually absorbed moisture1 which is taken up first by the edges exposed to the air4 ,this causes unequal expansion of the fibres with the production of the so-called wavy edges4 ,the only remedy in such cases is the free exposure of the sheets before printing1 so that the moisture is absorbed equally all over the sheet4 ,the cracked edges of envelopes may be explained by reference to the same conditions4 ,the paper is worked up into envelopes in an over-dry condition1 and the fibres1 being somewhat brittle1 readily break apart from one another4 ,if the paper is kept in stock for some time before use this defect can be very largely remedied4 ,with supercalendered papers it is only possible to obtain the best results by allowing the paper to stand for several days after making before it is glazed4 ,it is evident from these few examples that many of the troubles experienced by printers are due to the fact that orders for paper are frequently accompanied by an instruction for immediate delivery1 under which circumstances it is impossible to obtain the best results4 ,the expansion of papers used for lithography1 and the bad register frequently seen in colour work1 may be explained by reference to the behaviour of the individual fibres towards moisture4 ,the expansion is usually greater in one direction of the paper than in the direction at right angles to it1 and this is due to the fact that fibres have a greater ratio of expansion in the diameter than in the length4 ,the behaviour of papers when damped is a peculiarity well known to paper-makers and printers4 ,for certain purposes it is desirable that paper should not show any material alteration when damped1 since any expansion of the sheet is liable to throw the printing out of register4 ,the liability of papers to such stretch or expansion is largely minimised by careful manipulation of the pulp during the process of beating1 and also by a proper regulation of the web of paper as it passes from the wet end of the paper machine over the drying cylinders to the calenders4 ,the paper which fulfils the necessary qualifications as to a minimum stretch is prepared from pulp which has not been beaten for too long a period1 so that the pulp obtained is fairly light and bulky4 ,by this means the expansion of the fibres takes place in the sheet itself without making any material alteration in its size4 ,that is to say1 as the sheet of paper is fairly open1 there is sufficient room for expansion1 which thus takes place with the least alteration of the total area of the sheet4 ,the paper which is allowed to shrink on the machine during the process of drying1 without undue tension1 usually exhibits a minimum amount of expansion subsequently in printing4 ,it is important to notice that the expansion of paper is different for the two directions1 that is for the machine and cross directions4 ,this arises from the fact that in the machine-made paper the greater proportion of the fibres point in the direction of the machine while the paper is being made4 ,in consequence of this the expansion of the paper is greatest in what is known as the cross direction of the paper1 that is1 in the direction at right angles to the flow of the pulp along the machine wire4 ,this is to be explained by reference to the behaviour of fibres when damped or brought into contact with an excess of water4 ,the question of the exact changes in the dimensions of a fibre due to absorption of water has been dealt with in an interesting manner by ,hohnel4 ,he points out that the well-known peculiarity of the shrinkage of ropes which have been lying in the water can be explained by an examination of the behaviour of the single fibres4 ,he relates in detail the experiment which can be carried out for the exact observation of the fibres when in contact with water4 ,a dry fibre when soaked in water appears to become #bj to #cj per cent4 greater in diameter1 whereas in length it is usually only increased by one-tenth per cent4 ,the method adopted by ,hohnel was to place a fibre of convenient length on a glass slip down the centre of which was a fine narrow groove capable of holding water1 so that the fibre could be wetted4 ,over the fibre was a cover glass with a small scale marked on it4 ,the loose end of the fibres passed over a small roller and was stretched by a light weight4 ,the movements of the fibre were measured by means of an eye-piece micrometer4 ,in this way it is possible to determine alterations in length to within #jjje per cent41 and this variation can be directly seen under the microscope4 ,hohnel observes in his account of the experiments that all fibres become thicker when wetted1 that vegetable fibres are more susceptible than animal fibres4 ,animal fibres expand about #aj to #ad per cent4 in diameter1 but vegetable fibres as much as #bj per cent41 as shown in the following table3-- ---------------------------------------- ----------- ,animal ,fibre4 ,per ,cent4 ,vegetable ,fibre4 ,per ,cent4 ---------------------------------------- ----------- ,human hair #ajfg ,new ,zealand flax #bjj ,angora wool #ajb ,aloe hemp #beh ,alpaca wool #acg ,hemp #bbg ,tussah silk #aaj ,cotton #bge ---------------------------------------- ----------- ,the reverse is the case when the expansion of the fibres in regard to length is considered1 since animal fibres expand #jej to #ajj per cent4 of their length1 and vegetable fibres only #jje to #jaj per cent4 ,the maximum amount of expansion in the case of the vegetable fibres is obtained by gently breathing upon them rather than by the use of an excess of water4 ,these figures are important as explaining many of the peculiar characteristics of vegetable and animal fibres4 ,advantage is taken of the greater expansion of the latter in the manufacture of instruments for the measurement of moisture1 such as the hair hygrometer1 in which the elongation of a stretched hair registers the variation in the moisture of the atmosphere4 ,quality of ,book ,papers4--,the ,committee of the ,society of ,arts in dealing with the evidence as to the permanence of finished papers suggest the following classification as indicating the desired standards of quality3-- 7,a7 ,,classification ,,as ,,to ,,fibres4 ,a4 ,cotton1 flax1 and hemp4 ,b4 ,wood celluloses1 7a7 sulphite process1 and 7b7 soda and sulphate process4 ,c4 ,esparto and straw celluloses4 ,d4 ,mechanical wood pulp4 ,the ,committee find little fault with the ,principles which govern the trade in the manufacture of high-class papers1 and limit the result of their investigation to the suggestion of a normal standard of quality for book papers required in documents of importance according to the following schedule3-- ,fibres4--,not less than #gj per cent4 of fibres of ,class ,a4 ,sizing4--,not more than #b per cent4 rosin1 and finished with the normal acidity of pure alum4 ,loading4--,not more than #aj per cent4 total mineral matter 7ash74 ,with regard to written documents1 it must be evident that the proper materials are those of ,class ,a1 and that the paper should be pure1 sized with gelatine and not with rosin4 ,all imitations of high-class writing papers1 which are in fact merely disguised printing papers1 should be carefully avoided4 ,these recommendations are good as far as they go1 but in order to establish the proper standards of quality some specifications must be laid down with regard to the strength of the paper and its physical properties1 together with a reference to the use for which the paper is intended4 ,the physical condition of the paper itself apart from the nature of the fibre has much to do with its resistance to wear and tear1 and this is easily proved by comparing modern book papers made from esparto with book papers of an earlier date made from the same material4 ,the only official schedule of requirements in relation to public documents is that issued by the ,stationery ,office4 ,the details set out relate chiefly to questions of weight and strength1 the limits being expressed in definite form and not allowing much margin for variation in respect of strength or fibrous constituents4 ,mechanical wood pulp is excluded in all papers except common material as stated in the schedule4 ,the papers required for stock are divided into twelve classes4 ,in each class the trade names of various sized papers are given1 the size of the sheet and the weight of the ream1 and1 where required1 any special characteristics are set out4 ,the schedule is as follows3-- ,class #a4 ,hand-made or ,mould-made4 ,general ,specification4--,hand-made or mould-made4 ,animal tub-sized4 7,hand-made or ,mould-made to be marked on the wrapper47 ,where special water-marking is required mould will be supplied by the ,stationery ,office for those papers made by hand4 ,class #b4 ,writings1 ,air-dried4 ,general ,specification4--,plate rolled4 ,machine made4 ,animal tub-sized4 ,air-dried4 7,must bear ink after erasure47 ,note4--,the mean breaking strain and mean stretch required are given for each paper4 ,the figures represent the mean of the results obtained for both directions of the sheet1 and are calculated on a strip of paper five-eighths of an inch wide and having a free length of seven inches between the clips4 ,class #c4 ,writings1 ,ordinary4 ,general ,specification4--,rolled4 ,machine-made4 ,animal tub-sized4 ,class #d4 ,writings1 ,coloured4 ,specification4--,highly rolled4 ,machine-made4 ,animal tub-sized4 ,class #e4 ,blotting ,papers4 ,specification4--,all rag4 ,machine-made4 ,free from loading4 ,class #f4 ,printing and ,lithographic ,papers4 ,general ,specification4--,rolled4 ,machine-made4 ,engine-sized4 ,loading not to exceed #ae per cent4 ,class #g4 ,coloured ,printings4 ,general ,specification4--,rolled4 ,machine-made4 ,engine-sized4 ,class #h4 ,copying and ,tissue ,papers4 ,specification4--,machine-made4 ,free from loading4 7,copying papers are required to give three good copies47 ,class #i4 ,brown ,papers1 ,air-dried4 ,specification4--,air-dried4 ,machine-made4 ,note4--,the mean breaking strain and mean stretch required are given for each paper4 ,the figures represent the mean of the results obtained for both directions of the sheet1 and are calculated on a strip of paper two inches wide and having a free length of seven inches between the clips4 ,in the case of papers indicating a larger breaking strain than the minimum required1 a proportional increase in the stretch must also be shown4 ,class #aj4 ,brown ,paper1 ,cylinder-dried4 ,general ,specification4--,machine-made4 ,note4--,the mean breaking strain required is given for each paper4 ,the figures represent the mean of the results obtained for both directions of the sheet1 and are calculated on a strip of paper two inches wide and having a free length of seven inches between the clips4 ,class #aa4 ,smallhands4 ,general ,specification4--,machine-made4 ,engine-sized4 ,class #ab4 ,buff ,papers4 ,specification4--,highly finished both sides4 ,machine-made4 ,hard engine-sized4 ,mechanical wood pulp must not be used in the manufacture of any papers1 with the exception of engine-sized coloured printings1 and buff papers1 where an addition up to #be per cent4 will be allowed4 ,all animal tub-sized papers are required to be as far as possible free from earthy matter2 and1 except where specially stated1 the amount of loading added to other papers must not exceed #f per cent4 ,when sulphite or soda pulps are used1 either separately or conjointly1 in the manufacture of printing papers1 the quantity of neither material shall separately exceed #ej per cent4 ,the most complete specification as to the requirements for standard papers is that published by the ,paper ,testing ,institute in ,germany1 and used as the basis of most contracts1 at least for public and official documents4 ,standards of ,quality in ,germany4--,the classification of papers according to the raw materials used and the nature of the finished paper is very complete4 ,the classification is made under three headings3 7,a7 ,raw ,material2 7,b7 ,strength2 7,c7 ,uses4 7,a7 ,classification according to ,material4 7#a7 ,paper made from rags only 7linen1 hemp1 and cotton74 7#b7 ,paper made from rags with a maximum of #be per cent4 of cellulose from wood1 straw1 esparto1 manila1 etc41 but free from mechanical wood pulp4 7#c7 ,paper made from any fibrous material1 but free from mechanical wood pulp4 7#d7 ,paper of any fibrous material4 7,b7 ,classification according to ,strength4 ---------------------------------------- ----------------------- ,class #a4 #b4 #c4 #d4 #e4 #f4 ---------------------------------------- ----------------------- ,mean tearing length in metres #f1jjj #e1jjj #d1jjj #c1jjj #b1jjj #a1jjj ,elasticity per cent4 #d #ce #c #be #b #ae ,resistance to folding 7,schoppers' method1 number of foldings7 #aij #aij #hj #dj #bj #c ---------------------------------------- ----------------------- ,the tests for tearing length1 resistance to folding1 elasticity1 etc41 are made in air showing relative humidity of #fe per cent4 ,the calculations for tearing length are made on strips of paper dried at #ajj ,c4 7,c7 ,classification according to ,use4 ---------------------------------------- --------------------------- ,weight of ,fibre4 ,strength4 ,size of -------------- ,class4 ,uses4 ,class4 ,class4 ,sheets4 #a1jjj #a ,sq4 ,cm4 ,sheets4 ,metre4 ,kg4 ,grms4 ---------------------------------------- ------------------------- #a ,writing papers for important documents #a #a #cc #db #ae -- ,paper for ,state documents #a #a #bfe #db #ab -- #b ,paper for registers1 account books1 and ledgers-- 7a7 ,first quality #a #b #cc #db #ad -- 7b7 ,second quality #a #c #cc #db #ac -- #c ,documents intended to be preserved longer than ten years-- 7a7 ,foolscap paper #b #c #cc #db #ac -- ,letter paper 7quarto size7 #b #c #bfe #db #ajd -- ,letter paper 7octavo size7 #b #c #bfe #ba #eb -- ,duplicating paper #b #c #cc #db #g -- 7b7 ,official writing paper #b #d #cc #db #ac -- #d ,paper for documents of lesser importance-- 7a7 ,foolscap paper #c -- #cc #db #ab -- ,letter paper 7quarto size7 #c -- #bfe #db #if -- ,letter paper 7octavo size7 #c -- #bfe #ba #dh -- 7b7 ,official writing paper #c #d #cc #db #ab -- #e ,envelopes and wrappers-- 7a7 ,first quality -- #c -- -- -- 7b7 ,second quality -- #e -- -- -- #f ,writing paper of medium quality -- #e-f -- -- -- #g ,covers for documents-- 7a7 ,that required for frequent use #a ,tearing #cf #dg #hab #dhj length #b1ejj ,elasticity #ce 7b7 ,for other purposes #c ,tearing #cf #dg #dbc #bej length #b1ejj ,elasticity #be #h ,printing paper-- 7a7 ,for important printed matter #a #d -- -- -- 7b7 ,for less important printed matter #c #d -- -- -- 7c7 ,for common use -- #e-f -- -- -- ---------------------------------------- -------------------------- ,,chapter ,,xiii ,,bibliography ,,analysis1 ,,technology1 ,,etc4 ,,abel1 ,,dr4 ,e4 ,hypochlorite und electrische ,bleiche4 ,halle1 #aije4 ,,arabol ,,manufacturing ,,co4--,theory and ,practice of the ,sizing of ,paper4 ,new ,york1 #ho1 #ahie4 ,,behrens1 ,h4--,anleitung zur mikrochemischen ,analyse der wichtigsten ,verbindungen4 ,heft #b4 ,die wichtigsten ,faserstoffe4 ,hamburg und ,leipzig1 #ahif4 ,,beveridge1 ,j4--,paper-makers' ,pocket ,book4 ,london1 sm4 #ho1 #aija4 ,,bourdillat1 ,e4 ,die ,entfrbung und das ,bleichen der ,hadern4 ,weimar1 #ahfg4 ,,corput1 ,e4 ,,van ,,den4--,de la fabrication du papier au point de vue de la technologie chimique4 #b;e d4 ,paris1 #ho1 #ahfa4 ,,cross1 ,c4 ,f4 ,,and ,,bevan1 ,e4 ,j4--,a ,text-book of ,paper-making4 ,london1 sm4 #ho1 #ahhh4 ,ditto1 #bnd edition4 #aijj4 ,ditto1 #crd edition4 #aijg4 ,,cross ,,and ,,bevan4--,manuel de la fabrication du papier4 ,traduit de la #b;e dition ,anglaise4 ,par ,l4 ,desmarest4 #aijb4 ,,cross1 ,,bevan1 ,,beadle ,,and ,,sindall4--,the ,c4,b4,s4 ,units3 a ,book on ,paper ,testing4 #aijd4 ,,deterioration ,,of ,,paper4--,society of ,arts ,report4 #ahih4 ,,engelhardt1 ,b4 ,hypochlorite und electrische ,bleiche 7,technisch-,constructiver ,teil74 ,halle1 #aijd4 ,,engels1 ,j4 ,a4--,ueber ,papier und einige andere ,gegenstnde der ,technologie und ,industrie4 ,duisburg1 sm4 #ho1 #ahjh4 ,,engl,,nder4--,technologie der ,papierfabrikation4 ,lehrbuch fr ,spezialkurse an ,handelsfachschulen u4 fachlich4 ,fortbildungsschulen sowie ,lehrbehelf zum ,selbststudium4 #aijf4 ,,erfurt1 ,j4 ,frben des ,papierstoffs4 ,mit #ade ,proben in ,stoffgefrbten ,papiere1 #bte ,aufl4 ,berlin1 #ho1 #aijj4 ,,erfurt1 ,j4 ,the ,dyeing of ,paper ,pulp2 from the #bnd ,german edition1 by ,j4 ,hbner4 ,london1 #ho1 #aija4 ,,finkener4--,ueber die quantitative ,bestimmung des ,holzschliffes in ,papier nach ,goddefroy und ,coulon4 #ahib4 ,,flatters4--,microscopical ,research4 #aijf4 ,,griffin1 ,r4 ,b4 ,,and ,,little1 ,a4 ,d4--,the ,chemistry of ,paper-making1 with ,principles of ,general ,chemistry4 ,new ,york1 #ho1 #ahid4 ,,hassak4--,wandtafeln fr ,warenkunde u4 ,mikroskopie4 #aijd4 ,,haywood1 ,j4 ,k4--,arsenic in ,papers and ,fabrics4 #aijd4 7,u4,s4,a4 ,department of ,agriculture47 ,,herzberg1 ,w4--,mikrosk4 ,untersuchung des ,papiers4 #ahhg4 ,,herzberg1 ,w4--,papierprfung4 ,leitf4 bei d4 ,unters4 v4 ,papier4 #ahhh4 ,ditto1 #bnd edition4 #aijb4 ,ditto1 #crd edition4 #aijg4 ,,herzberg1 ,w4--,paper ,testing as carried out in the ,government ,laboratory at ,charlottenburg4 ,from the ,german1 by ,p4 ,n4 ,evans1 ,london1 #ho1 #ahib4 ,,herzberg1 ,w4--,mitteilungen aus den ,knigl4 technischen ,versuchsanstalten zu ,berlin4 #ahhg1 et seq4 ,h,,hnel1 ,f4 ,v4--,die ,mikroskopie der technisch verwendeten ,faserstoffe4 #aije4 ,h,,lbling1 ,v4--,die ,fabrikation der ,bleichmaterialien4 ,berlin4 ,,hoyer1 ,e4--,le papier2 tude sur sa composition1 analyses et essais4 ,de l',allemand4 ,paris1 #ho1 #ahhd4 ,,hoyer-,,kraft4--,die ,spinnerei1 ,weberei und ,papierfabrikation1 #d ,aufl4 #aijd4 ,,jagenberg1 ,f4--,die thierische ,leimung fr endloses ,papier4 ,berlin1 #ho1 #ahgh4 ,,johannsen4--,mitteilungen ber ,mikrophotographie von ,faserstoffen im durchfallenden und auffallenden ,licht4 #aijf4 ,,klemm1 ,p4--,papier ,industrie ,kalender4 #ahih1 et seq4 ,,lauboeck4--ber die ,saugfhigkeit der ,lschpapiere4 ,mitteilungen des k4k4 ,technologischen ,gewerbe-,museums4 ,wien1 #ahig4 ,,leach1 ,c4 ,e4--,on the ,shrinkage of ,paper 7excerpt74 ,newcastle1 #ho1 #ahhd4 ,,martens1 ,a4--,mitteilungen aus den ,knigl4 ,technischen ,versuchsanstalten 7jhrlich74 ,erscheinen seit #ahhc4 ,die ,jahrgnge #ahhd bis #aijc enthalten aus der ,abteilung fr ,papierprfung die im ,jahrgang #aije1 dieses ,kalenders verzeichneten ,arbeiten4 ,,martens1 ,a4--,apparaten zur ,untersuchung der ,festigkeitseigenschaften von ,papier4 ,knigl4 ,techn4 ,versuchsanstalten4 ,mitteilungen4 ,ergnzungsheft4 ,no4 #c4 #ho1 #ahhg4 ,,martens1 ,a4--,ueber ,druckpapier der ,gegenwart4 ,knigl4 ,techn4 ,versuchsanstalten4 ,mittheilungen4 ,ergnzungsheft4 ,no4 #d4 #ho1 #ahhg4 ,,martens1 ,a4--,untersuchung ,japanischer ,papiere4 ,knigl4 ,techn4 ,versuchsanstalten4 ,mittheilungen4 ,ergnzungsheft4 ,no4 #d4 #ho1 #ahhh4 ,,martens ,,und ,,guth4--,das knigliche ,materialprfungsamt der technischen ,hochschule ,berlin auf dem ,gelnde der ,domne ,dahlem beim ,bahnhof ,gross-,lichterfelde ,west4 ,berlin1 #aijd4 ,,melnikoff1 ,n4--,prfung von ,papier und ,pappe nebst ,adressbuch der russischen ,papierfabriken4 ,petersburg1 #aijf4 ,m,,ller1 ,l4--,die ,fabrikation d4 ,papiers in ,sonderheit d4 a4 d4 ,maschine gefertigten4 #b ,aufl4 #ahee4 ,m,,ller ,,und ,a4 ,,haussner4--,die ,herstellung u4 ,prfung des ,papiers4 #aije4 ,m,,ller1 ,a4--,qualitative und quantitative ,bestimmung des ,holzschliffes im ,papier4 #ahhg4 ,,muth4 ,die ,leimung der ,papierfaser im ,hollnder und die ,anfertigung fester ,papiere4 #ahij4 ,,naylor1 ,w4--,trades ,waste4 ,london1 #aijb4 ,,normalpapier4--,sammlung der ,vorschriften fr amtliche ,papier- und ,tintenprfung4 ,berlin1 #ahib4 ,,piette1 ,l4--,trait de la coloration des ptes papier4 ,prcd d'un aperu sur l'tat actuel de la fabrication du papier4 ,avec chantillons de papiers colors4 ,paris1 #ho1 #ahfc4 ,,rejt1 ,a4--,anleitung fr ,private zur ,durchfhrung der ,papierprfung4 ,budapest1 #ahic4 ,,rossel4--,papiere und ,papierprfung mit ,bercksichtigung der in der ,schweiz verwendeten ,schreib- und ,druckpapiere4 ,biel1 #ahie4 ,,schumann1 ,,dr4 ,g4--,welche ,ursachen bedingen die ,papierqualitt4 ,biberach1 #aija4 ,,sindall1 ,r4 ,w4--,paper ,technology4 ,london1 #aijf4 ,,stevens1 ,h4 ,p4--,the ,paper ,mill ,chemist4 ,london1 #aijg4 ,,wiesner1 ,j4--,mikroskopische ,untersuchung des ,papiers mit besonderer ,bercksichtigung der ltesten orientalischen und europischen ,papiere4 ,wien1 #ahhg4 ,,wiesner1 ,j4--,mikroskopische ,untersuchung alter ostturkestanischer und anderer asiatischer ,papiere nebst histologischen ,beitrgen zur mikroskopischen ,papieruntersuchung4 ,wien1 #aijb4 ,,winkler1 ,o4--,die ,trockengehalts-,bestimmung d4 ,papierstoffe4 #aijb4 ,,winkler1 ,o41 ,,und ,,karstens1 ,h4--,papieruntersuchung4 #aijc4 ,,wurster4--,le collage et la nature du papier4 ,paris1 #aija4 ,,wurster1 ,,dr4 ,c4--,die neuen ,reagentien auf ,holzschliff und verholzte ,pflanzenteile zur ,bestimmung des ,holzschliffs im ,papier4 ,berlin4 ,,zirm1 ,a4--,der ,papierfrber4 ,tilsit1 #aijd4 ,,cellulose1 ,,etc4 ,,beadle1 ,c4--,viscose and ,viscoid4 ,franklin ,institute reprint4 #ahif4 ,,bersch1 ,j4--,cellulose1 ,celluloseprodukte u4 ,kautschuksurrogate4 #aijc4 ,,bockmann1 ,f4--,das ,celluloid1 sein ,rohmaterial1 ,fabrikation1 ,eigenschaften u4 technische ,verwendung4 #ahhj4 #bte ,aufl4 #ahid4 ,,bornemann1 ,,gr4--,ueber ,cellulose and neuere ,umwandlungsprodukte derselben4 ,biberach1 #aija4 ,,bottler1 ,m4--,die vegetabilischen ,faserstoffe--,hartleben's chemisch-technische ,bibliothek4 #aijj4 ,,butschli1 ,o4--,untersuchgn4 an ,gerinnungsschaumen1 ,sphrokystallen u4 d4 ,struktur v4 ,cellulose4 #ahid4 ,,cross1 ,c4 ,f41 ,,and ,,bevan1 ,e4 ,j4--,cellulose4 ,london1 #ahhe4 #bnd edition4 #ahie4 ,,cross ,,and ,,bevan4--,researches on ,cellulose4 #ahie-aijj4 ,ditto1 #aijj-aije4 ,,margosches1 ,,dr4 ,b4--,die ,viskose1 ihre ,herstellung1 ,eigenschaften und ,anwendung4 ,leipzig1 #aijf4 ,,schlesinger4--,knstliche ,seide 7,zellstoff-,seide74 ,mechanisch-technologische ,untersuchung der aus nitriertem ,zellstoffs hergestellten ,seide4 #ahie4 ,,fibres1 ,,etc4 ,,and,s1 ,l4 ,e4--,die ,verarbeitung des ,strohes4 ,wien1 #ahih4 ,,bagshaw4--,photomicrography4 ,elementary4 ,,bengal ,,government4--,jute in ,bengal1 and on ,indian ,fibres available for the ,manufacture of ,paper4 ,report by ,h4 ,kerr4 ,calcutta1 fol41 #ahgd4 ,,bleekrode1 ,s4--,grondstoffen voor ,papierbereiding1 bijzonder in ,neerlandsch-,indi 7excerpt74 #ho1 #ahei4 ,,bottler1 ,m4--,die animalischen ,faserstoffe4 #aija4 ,,carter4--,spinning of ,fibres4 #aijd4 ,,cobbett4--,a ,treatise on ,cobbett's ,corn4 #ahbh4 7,printed on paper made of corn husks47 ,,christy4--,commercial ,plants and ,drugs4 #ahhb4 ,,cross ,,and ,,bevan4--,report on ,indian ,fibres4 #ahhg4 ,,cross1 ,c4 ,f4--,report on ,miscellaneous ,fibres4 #ahhf4 ,,cross1 ,c4 ,f4--,bast ,fibres4 ,manchester1 #ahhj4 ,,dalen1 ,g4--,jute4 ,manila1 ,adansonia4 #aijb4 ,d,,pierre1 ,j4--,trait des apprts et spcialement des tissus de coton1 blancs1 teints et imprims4 ,,dodge1 ,c4 ,r4--,leaf ,fibres of the ,united ,states4 #aijc4 ,,gar,,on1 ,,jules4--,bibliographie de la technologie chimique des fibres textiles4 ,paris1 #ahic4 ,,gelder ,,zonen1 ,,van4--,een woord over nieuwe ,grondstoffen voor ,papier1 met monsters van ded proeven1 etc4 ,amsterdam1 sm4 #do1 #ahff4 ,,georgievics1 ,g4 ,v4--,lehrbuch der chemischen ,technologie der ,gespinnstfasern4 #ahie-ih4 ,,georgievics1 ,g4 ,v4--,lehrbuch d4 chemischen ,technologie d4 ,gespinnstfasern4 #bte ,tle4 #ahih-aijb4 ,,georgievics1 ,g4 ,v4--,technology of ,textile ,fibres2 from the ,german4 #aijb4 ,,grothe1 ,h4--,die ,technologie der ,gespinnstfasern4 #ahgf-hb4 ,,goodale4--,physiological ,botany4 #ahij4 ,,hammarsten1 ,o4--,untersuchungen ber d4 ,faserstoffgewinnung1 #ahge4 ,,hannan1 ,w4 ,i4--,textile ,fibres of ,commerce4 #aijb4 ,,hoyer1 ,e4 ,,von4--,die ,verarbeitung der ,faserstoffe4 7,spinnerei1 ,papierfabrikation47 #cte ,aufl4 #aijj4 ,,johnstone4--,esparto4 7,society of ,arts ,lecture47 #ahgj4 ,,kew ,,bulletin4--,vegetable ,fibres4 #aija4 ,,lecomte1 ,h4--,les textiles vgtaux2 leur examen microchimique4 ,paris1 #ahia4 ,,liotard4--,materials in ,india suitable for ,paper-making4 ,calcutta1 #ahhj4 ,,morris1 ,,dr4--,commercial ,fibres4 7,cantor ,lectures47 #ahie4 ,m,,ller1 ,,hugo4--,pflanzenfaser4 ,leipzig1 #ahgc4 ,,payen1 ,a4--,succdans des chiffons4 ,paris ,universal ,exhibition4 ,rapports du ,jury ,international1 ,classe #g1 sect4 ii4 #ho1 #ahfg4 ,,pfuhl1 ,e4--,papierstoffgarne1 ihre ,herstellung1 ,eigenschaften u4 ,verwendbarkeit4 #aijd4 ,,posselt1 ,e4 ,a4--,the ,structure of ,fibres1 ,yarns1 and ,fabrics1 being a ,practical ,treatise for the use of all persons employed in the ,manufacture of ,textile ,fibres4 #b vols41 #aijb4 ,,rostaing ,,and ,,others4--,prcis historique1 descriptif1 analytique et photomicrographique1 des vgtaux propres la fabrication de la cellulose et du papier4 ,paris1 #ho1 #aijj4 ,,routledge1 ,t4--,bamboo considered as a ,paper-making ,material1 with ,remarks upon its ,cultivation and ,treatment4 ,london1 #ho1 #ahge4 ,,routledge1 ,t4--,bamboo and its ,treatment4 #ahgi4 ,,silbermann1 ,h4--,fortschritte auf dem ,gebiete der chemischen ,technologie d4 ,gespinnstfasern1 #ahhe-aijj4 #bte ,tle41 #aijb-jc4 ,,trabut4--tude sur l'alfa4 #ahhi4 ,,urbain1 ,v4--,les succdans du chiffon en papeterie4 ,paris1 #afo1 #ahig4 ,v,,tillart4--tudes sur les ,fibres ,vgtales4 ,paris1 #ahgf4 ,,wieck1 ,f4 ,g4--,bilder aus ,gewerbskunst 7aus ,tomlinson's ,objects in ,art ,manufacture71 i4 ,papier4 ,leipzig1 sm4 #ho1 #ahee4 ,,witt1 ,o4 ,n4--,chemische ,technologie der ,gespinnstfasern1 ihre ,geschichte1 ,gewinnung1 ,verarbeitg4 u4 ,veredlung4 #ahhh-aijb4 ,,zetzsche4--,die ,wichtigsten ,faserstoffe der europischen ,industrie4 ,anleitung zur ,erkennung und ,unterscheidung4 #aije4 ,,zimmermann1 ,a4--,morphologie und ,physiologie der ,pflanzenzelle4 ,,historical4 ,,blanchet1 ,,augustin4--,essai sur l'histoire du papier et de sa fabrication4 ,paris1 #aijj4 ,,breitkoff1 ,j4 ,g4 ,j4--,ursprung der ,spielkarten1 die ,einfhrung des ,leinenpapieres1 etc41 in ,europa4 7,completed by ,j4 ,g4 ,f4 ,roch47 ,leipzig1 #b vols41 #do1 #aghd-ahja4 ,,briquet1 ,c4 ,m4--,bemerkungen ber das ,sammeln von ,wasserzeichen oder ,papiermarken1 berreicht bei der ,ausstellung der alten ,papiermarkerkunst zu ,paris4 #aijj4 ,,briquet1 ,c4 ,m4--,papiers et filigranes des archives de ,gnes #aaed-agjj4 ,geneva1 #ahhh4 ,,briquet1 ,c4 ,m4--,geschichte der ,papierzeichen von ihrem ,erscheinen gegen #abhb bis #afjj4 ,mit ,beigabe von #aeejj4 #aijf4 ,,butler ,,paper ,,co4--,the ,story of ,paper-making4 ,chicago1 sm4 #ho1 #aija4 ,,collett1 ,c4 ,d4--,history of ,taxes on ,knowledge4 ,london1 #ahii4 ,,congress4--,international congress de fabricants de papier et carton1 ,antwerp4 ,comptes rendu des sances4 ,bruxelles1 #ho1 #ahid4 ,,dropisch1 ,b4--,die ,papiermaschine1 ihre geschichtliche ,entwicklung u4 ,construction4 #ahgh4 ,,egger1 ,e4--,le papier dans l'antiquit et dans les temps modernes4 ,paris1 #afo1 #ahff4 ,,evans1 ,l4--,the ,firm of ,john ,dickinson ,co41 with an ,appendix on ,ancient ,paper-making4 ,london1 sm4 #ho1 #ahif4 ,,gamble1 ,j4--,collection of ,documents 7,specifications1 ,official ,reports1 etc47 respecting the ,claims of ,l4 ,robert as the ,original ,inventor1 and of ,j4 ,gamble as the ,first ,introducer of the ,french ,paper-machine4 ,fol41 #ahja--eh4 ,,hoernle1 ,a4 ,f4--,who was the ,inventor of ,rag ,paper8 #aijc4 ,h,,ssle1 ,f4 ,,von4--,geschichte der alten ,papiermhlen in ehemaligen ,stift ,kempten und in der ,reichsstadt ,kempten4 #aija1 #do1 #aijj4 ,,hunter1 ,j4--,specimen of ,marks used by ,early ,manufacturers of ,paper 7,excerpt74 ,london1 #do1 #aheh4 ,,imberdis1 ,j4--,le papier ou l'art de fabriquer de papier4 ,traduction au ,franais de 7papyrus sive ars conficiend papyri1 #afic71 par ,a4 ,blanchet4 ,avec le texte latin4 #ahii4 ,,jackson1 ,j4 ,b4--,an ,essay on the ,invention of ,engraving and ,printing in ,chiaro ,oscuro1 as practised by ,durer1 etc41 and its ,application to the ,making of ,paperhangings4 ,london1 sm4 #do1 #aged4 ,,jansen1 ,h4--,essai sur l'origine de la gravure1 etc4 ,paris1 #b vols41 #ho1 #ahjh4 ,,jenkins1 ,r4--,paper-making in ,england1 #adie1 etc41 from the ,library ,association ,record1 ,september1 #aijj-;,april1 #aijb4 ,london1 #ho4 ,,karabacek1 ,j4--,das arabische ,papier4 ,wien1 #ahhg4 ,,kent ,,co4--,paper and ,paper-making ,chronology4 ,london1 #ho1 #ahge4 ,,kirchner1 ,e4--,die ,papiere des ,,xiv4 ,jahrhunderts im ,stadtarchive zu ,frankfurt a4 ,m4 #ahic4 ,,kirchner1 ,e4--,das ,papier4 ,die ,geschichte d4 ,papierindustrie2 die ,rohstofflehre d4 ,papierindustrie4 #c ,bde41 #ahig-ii4 ,,kirchner1 ,e4--,das ,papier4 ,historisch-technologische ,skizzen4 ,jahresbericht der ,techn4 ,lehranstalten in ,chemnitz4 #aijc4 ,,klein1 ,a4--,entwicklung und ,aufgaben der ,papierindustrie4 ,biberach1 #aijf4 ,,klemm1 ,p4--,papier-warenzeichen 444 vom #a ,okt41 #ahid1 bis ,ende #aijb1 fr ,klasse #bg1 umfassend ,papier1 etc41 eingetragenen ,wort- und ,bildzeichen4 ,leipzig1 sm4 #ho1 #aijc4 ,,koops1 ,m4--,historical ,account of ,paper1 and of ,substances used prior to its ,invention 7printed on paper made from straw and wood74 ,london1 #ho1 #ahjj4 ,ditto1 #bnd edition1 #ahja4 ,,lacroix1 ,a4--,historique de la papeterie d',angoulme suivi d'observations sur le commerce de chiffons en ,france4 ,paris1 #ho1 #ahfc4 ,,lalande1 ,j4 ,j4 ,,le ,f4 ,,de4--,l'art de faire le papier4 ,acad4 ,roy4 des sciences4 ,description des ,arts et ,mtiers1 vol4 #a4 ,fol41 #agfa4 ,,lettre sur les dcouvertes de ,m4 ,didot an dans les arts de 444 la papeterie 7l'invention du papier-vlin74 ,paris1 #abo1 #aghc4 ,,leuchs1 ,j4 ,c4--,beschreibung der in den letzten acht ,jahren in der ,papierfabrikation gemachten ,verbesserungen4 ,nachtrag4 ,nrnberg1 #ho1 #ahbh4 ,,marabini4--,bayrische ,papiergeschichte4 #a ,teil4 ,die ,papiermhlen im ,gebiete der weiland freien ,reichsstadt ,nrnberg4 ,nrnberg1 #ahid4 ,,maurel1 ,f4--,le papier japonais4 ,histoire et fabrication d'aprs les documents ,anglais et indignes 7excerpt74 ,paris1 #do1 #ahga4 ,,meerman1 ,g41 ,,and ,,others4--,epistol1 etc41 de chart vulgaris line origine4 ,ed4 ,j4 ,van ,vassen1 ,hag ,com4 ,sm4 #ho1 #agfg4 ,,midoux1 ,e41 ,,and ,,matton1 ,a4--tude sur les filigranes des papiers employs en ,france aux #ad;e et #ae;e sicles4 ,paris1 #ho1 #ahfh4 ,,millar1 ,o4--,papier-,industrie4 ,schweizerische ,landesausstellung1 #ahhc4 ,berichte1 ,gruppe #h1 #ahhd4 ,,murray1 ,j4--,practical ,remarks on ,modern ,paper1 etc41 with an ,introductory ,account of its ,former ,substitute4 ,edinburgh1 #ho1 #ahbi4 ,,parlatore1 ,p4--,mmoire sur le papyrus des ,anciens et sur le papyrus de ,sicile1 ,acad4 des ,sciences4 ,paris4 ,mm4 par divers ,savans4444 #b;e ,serie1 ,tome #ab4 #do1 #ahed4 ,,peignot1 ,e4 ,g4--,essai sur l'histoire du parchemin et du vlin4 ,paris1 #ho1 #ahab4 ,,penig4--7,patentpapierfabrik zu ,penig47 ,ein ,beitrag z4 ,geschichte d4 ,papiers1 #ahig4 ,,robert1 ,n4 ,l4--,le centenaire de la machine a papier continu4 ,son invention par ,n4 ,l4 ,robert en #agii4 ,biographie de l'inventeur1 par ,j4 ,breville4 ,historique des divers perfectionnements 444 par ,didot ,saint-,leger1 #ahjj-ahah4 ,paris1 #ho1 #aija4 ,,robertson4--,fifty ,years' ,experience in ,paper-making4 ,leith4 ,,schaeffer1 ,j4 ,c4--,proefnemingen en ,monster-,bladen om ,papier te maaken zonder ,lumpen of met een gering ,byvoegzel derzelven4 ,uit het ,hoogduits vertaald4 ,deel #a-b4 ,amsterdam1 #b vols41 sm4 #do1 #aggj4 ,,schaeffer1 ,j4 ,c4--,smtliche ,papierversuche1 #bte ,aufl4 ,nebst #ha ,mustern und #ac ,kupfertafeln4 ,regensburg1 #f vols4 in one1 sm4 #do1 #aggb4 ,,schaeffer1 ,j4 ,c4--,erweis in ,musterbogen dass die neuen ,papierarten 444 sich allerdings auch zu ,tapeten bermahlen und gebrauchen lassen4 ,regensburg1 fol4 ,,smith1 ,j4 ,e4 ,a4--,history of ,paper1 ,genesis and ,revelations4 ,holyoke1 ,mass41 ,u4,s4,a41 #ahhb4 ,,sotheby1 ,s4 ,l4--,the ,typography of the #aeth ,century 444 ,exemplified in a ,collection of ,facsimiles from #ajj ,works1 with their ,watermarks4 ,london1 fol4 #ahde4 ,,sotheby1 ,s4 ,l4--,principia ,typographica4 ,an ,attempt to ,elucidate the ,paper ,marks of the ,period4 ,london1 #c vols41 fol4 #aheh4 ,,spechthausen4--,hundert ,jahre der ,papierfabrik ,spechthausen4 ,festschrift1 z4 #ahhg4 ,,spicer1 ,a4--,the ,paper ,trade4 ,london1 #aijg4 ,,stoppelaar1 ,j4 ,h4 ,,de4--,het ,papier in de ,nederlanden gedurende de middeleeuwen1 inzonderheid in ,zeeland4 ,middelburg1 #ho1 #ahfi4 ,,tomlinson1 ,c4--,illustrations of the ,useful ,arts4 ,no4 #c1 ,paper4 ,london1 #cbo1 #ahei4 ,,villette1 ,c4 ,,marquis ,,de4--,,oeuvres1 with ,specimens of ,paper4 ,londres1 #afo1 #aghf4 ,,willkomm1 ,m4--ber den ,lotos und ,papyros der alten gypter und die ,papiererzeugung in ,altertume4 ,prag1 #ahib4 ,,paper ,,manufacture4 ,,archer1 ,t4 ,c4--,the ,manufacture of ,paper4 ,bevan4 ,british ,manufacturing ,industries1 viii4 ,sm4 #ho1 #ahgf4 ,,arnot4--,technology of the ,paper ,trade 7,cantor ,lecture1 ,society of ,arts74 ,london1 #ahgg4 ,,barse1 ,j4--tudes compares sur l'industrie ,franaise1 ii4 ,la fabrication et le commerce du papier en #ahfj et en #ahfd4 ,paris1 l4 #ho1 #ahfd4 ,,beadle1 ,c4--,paper ,manufacture--,lectures4 #aija4 ,,beadle1 ,c4--,chapters on ,paper-making4 ,vol4 #a4 ,london1 #aijd4 ,vol4 #b1 ,answers to ,technological ,questions4 #aijf4 ,vol4 #c1 ,practical ,points in ,paper ,manufacture4 #aijg4 ,vol4 #d1 ,ditto4 #aijg4 ,,beaumont1 ,f4--,report on ,apparatus and ,processes used in ,paper-making1 etc4 ,paris ,universal ,exhibition1 #ahfg4 ,british ,commercial ,reports1 ,vol4 #d4 #ho1 #ahfg4 ,,bennett1 ,j4 ,b4--,paper-making ,processes and ,machinery1 with ,illustrations of ,paper-making ,machinery constructed by ,bertrams1 ,ltd4 ,edinburgh1 #ho1 #ahib4 ,,bertrams1 ,,ltd4--,specimens of ,paper4 ,edinburgh1 obl4 #afo1 #ahib4 ,,blanchet1 ,a4--,fabrication du papier4 ,rapports1 ,paris ,universal ,exhibition1 #aijj4 ,,brown1 ,h4 ,t4--,the ,manufacture of ,paper from ,wood in the ,united ,states4 #ahhf4 ,,burot4--,note sur la fabrication du papier de paille4 ,paris1 #ho1 #ahhc4 ,,campredon1 ,e4--,le ,papier4 tude monographique sur la papeterie ,franaise et en particulier sur la papeterie ,charentaise4 i4 ,historical2 ii4 ,descriptive of ,modern ,paper-making2 iii4 ,co-operative ,paper-making4 ,paris1 #ho1 #aija4 ,,charpentier1 ,p4--,le ,papier4 ,fremy1 ,e4 ,encycl4 ,chim41 ,tome ,x4 #ho 7#hc71 #ahij4 ,,clapperton1 ,g4--,practical ,paper-making4 ,london1 sm4 #ho1 #ahid4 ,ditto1 #bnd edition1 #aijg4 ,,coney1 ,e4--,paper-making ,machinery and ,fibres4 ,philadelphia ,international ,exhibition1 #ahgf4 ,u4,s4,a4 ,centennial ,commission ,reports and ,awards1 ,group xiii4 #ho1 #ahgf4 ,,dalheim1 ,c4 ,f4--,taschenbuch f4 d4 prakt4 ,papierfabrikanten4 #cte ,aufl4 #ahif4 ,,dammer1 ,o4--,papierfabrikation4 ,,davis1 ,c4 ,t4--,the ,manufacture of ,paper4 ,philadelphia1 #ho1 #ahhf4 ,,doumerc ,,and ,,others4--,matriel et procds de la papeterie1 etc4 ,paris ,univ4 ,exhibition1 #ahfg4 ,rapports du ,jury ,international1 ,classe #ei4 #ho1 #ahfg4 ,,doyle1 ,p4--,paper-making in ,india1 being ,notes of a ,visit to the ,lucknow ,paper ,mill4 ,lucknow1 #ho1 #ahhe4 ,,dropisch1 ,b4--,handb4 d4 ,papierfabrikation4 #c;e ,aufl4 #ca ,taf4 in fol4 #ahha4 ,,dunbar1 ,j4--,the ,practical ,papermaker4 ,leith1 #abo1 #ahha4 ,,hartmann1 ,c4--,handb4 d4 ,papierfabrikation4 ,taf4 #ahdb4 ,,hassak1 ,k4--,die ,erzeugung des ,papieres4 ,,hausner1 ,a4--,der ,hollnder4 ,eine kritische ,betrachtung seiner ,arbeitsweise mit ,bezug auf die ,einzelabmessungen seiner ,teile und die verarbeiteten ,fasern4 #aija4 ,,herring1 ,r4--,paper and ,paper-making1 ,ancient and ,modern4 ,london1 #ho1 #ahed4 ,ditto1 #bnd edition1 #ahee4 ,ditto1 #crd edition1 #ahfc4 ,,hofmann1 ,c4--,a ,practical ,treatise on the ,manufacture of ,paper in ,all its ,branches4 ,philadelphia1 #do1 #ahgc4 ,,hofmann1 ,c4--,praktisches ,handbuch d4 ,papierfabrikation4 #ahgc4 ,,hoffmann1 ,,th4--,papierprgung4 ,berlin4 ,,hoyer1 ,e4--,das ,papier1 seine ,beschaffenheit und deren ,prfung4 ,mnchen1 #ahhb4 ,,hoyer1 ,e4--ber die ,entstehung und ,bedeutung der ,papiernormalien1 sowie deren ,einfluss auf die ,fabrikation des ,papieres4 ,mnchen1 #ahhh4 ,,hoyer1 ,e4--,die ,fabrikation des ,papiers4 #aijj4 ,,hoyer1 ,e4--,die ,fabrikation des ,papiers1 nebst ,gewinnung d4 ,fasern4 #ahhg4 ,h,,bner1 ,j4--,paper ,manufacture 7,cantor ,lectures to the ,society of ,arts74 #aijc4 ,,jagenberg1 ,f4--,das ,hollndergeschirr4 ,remscheid4 #ahid4 ,,kirchner-,,strohbach4--,hollnder-,theo rie4 ,biberach4 #aijd4 ,,klemm1 ,,dr4 ,p4--ber ,papier4 ,klimsch's ,graphische ,bibliothek ,bd4 #c 7,farbe und ,papier im ,druckgewerbe74 #b ,teil4 ,frankfurt a4 ,m4 #aijj4 ,,korschilgen ,,und ,,selleger4--,technik und ,praxis der ,papierfabrikation4 ,berlin1 #aijf4 ,,kraft1 ,m4--,grundriss der mechanischen ,technologie4 ,abt4 ii4 ,spinnerei1 ,weberei1 und ,papierfabrikation4 #bte ,aufl4 ,wiesbaden1 #ho1 #ahie4 ,,lenormand1 ,l4 ,s4--,manuel du fabricant de papier4 ,paris1 #b vols41 #aho1 #ahcc4 ,ditto1 #bnd edition4 #ahcd4 ,,lenormand1 ,l4 ,s4--,nouveau manuel complet du 444 fabricant de papiers peints4 ,nouv4 ed4 par ,vergnand4 ,paris1 #aho1 #ahed4 ,,lenormand1 ,l4 ,s4--,handbuch der gesammten ,papierfabrikation1 #bte ,aufl41 von ,c4 ,hartmann4 ,weimar1 #b vols41 #abo1 #ahfb4 ,,merz4--,behandlung der ,papiermaschine4 ,,meynier1 ,h4--,papier und ,papier-,fabrikate4 ,paris ,univ4 ,exhibition1 #ahfg4 ,austrian ,comm4 ,berichte4 ,heft #h4 #ho1 #ahfg4 ,,mierzinski1 ,,st4--,handbuch d4 ,papierfabrikation4 #c ,bde4 #ahhf4 ,m,,ller1 ,f4 ,a4 ,l4--,die ,fabrikation des ,papiers1 in ,sonderheit der auf der ,maschinen gefertigten1 etc4 #cte ,aufl4 ,berlin1 #ho1 #ahfb4 ,m,,ller1 ,,dr4 ,l4--,die ,fabrikation des ,papiers4 ,berlin1 #ahgg4 ,,olmer1 ,,georges4--,du papier mcanique4 ,,onfroy4--,l'art du papier et le papier d',arches4 #aijg4 ,,paper-,,making4--,paper-making1 by the ,editor of the ,paper ,mills ,directory1 ,london4 #bnd edition4 #ho1 #ahgf4 ,,paper-,,maker4--,the ,paper-makers' ,handbook and ,guide to ,paper-making1 by a ,practical ,paper-maker4 ,london1 sm4 #ho1 #ahgh4 ,,paper-,,manufacture4--,essays by a ,society of ,gentlemen4 ,no4 vi41 pp4 #ba-bg4 #agag4 ,,parkinson1 ,r4--,treatise on ,paper1 with ,outline of ,manufacture4 #ahhf4 ,ditto1 #bnd edition1 #ahif4 ,,payen1 ,a41 ,,and ,,others4--,la fabrication du papier et du carton4 #c;e ed4 ,paris1 #ho1 #ahha4 ,,payen1 ,a41 ,,and ,,vigreux1 ,l4--,la papeterie4 tudes sur l',exposition de #ahfg4 ,vol4 #h4 #ho1 #ahfg4 ,,pfau1 ,f4--,der junge ,papierhndler4 ,berlin1 #aijb4 ,,piette1 ,l4--,manuel 444 de papeterie et les succdans 7des chiffons74 ,paris1 #b vols41 #ho1 #ahfa4 ,,planche1 ,g4--,de l'industrie de la papeterie4 ,paris1 #ho1 #ahec4 ,,planche1 ,g4--,der ,papierfabrikation4 ,bearbeitet von ,c4 ,hartmann4 ,weimar1 #abo1 #ahec4 ,,planche1 ,g4--,bericht ber die ,reinigung der ,stoffe zur ,papierfabrikation4 ,uebersetzt und vervollstndigt durch eine chronologische ,skizze der ,papier-,erzeugung und der ,verbesserungen an den ,maschinen zur ,reinigung des ,papier-,stoffs von ,a4 ,rudel4 ,leipzig1 #ho1 #ahfb4 ,,prouteaux1 ,a4--,practical ,guide for the ,manufacture of ,paper and 7,paper7 ,boards4 ,with a chapter on ,wood ,paper in the ,u4,s4 by ,h4 ,t4 ,brown4 ,philadelphia1 #ho1 #ahff4 ,,prouteaux1 ,a4--,guide de la fabrication du papier et du carton4 ,paris1 #abo1 #ahfd4 ,,raab1 ,r4--,die ,schreibmaterialen und die gesamte ,papierindustrie4 ,hamburg1 #ahhh4 ,,reed1 ,a4 ,e4--,paper ,manufacture4 ,society for the ,promotion of ,scientific ,industry4 ,artisans' ,reports upon the ,vienna ,exhibition4 #ho1 #ahgc4 ,,richardson1 ,w4 ,h4--,the ,industrial ,resources of the ,tyne 444 ,paper4 #ahfd4 ,,schubert1 ,m4--,trait pratique de la fabrication de la cellulose4 ,trad4 p4 ,e4 ,bibas4 ,toile4 #ahic4 ,,schubert1 ,m4--,die ,praxis der ,papierfabrikation mit besond4 ,bercksichtigung der ,stoffmischungen und deren ,calculationen4 #ahig4 ,,schubert1 ,m4--,die ,papierverarbeitung4 #b ,bde4 #aijj-aija4 ,bd4 ,i4 ,die ,kartonnagen-,industrie4 ,bd4 ,,ii4 ,die ,buntpapierfabrikation4 ,,sindall1 ,r4 ,w4--,the ,manufacture of ,paper ,pulp in ,burma4 ,government ,press4 ,rangoon1 #aijg4 ,,sindall1 ,r4 ,w4--,the ,manufacture of ,paper4 #aijh4 ,constable ,co4 ,london4 ,,twerdy1 ,e4--,papier industrie4 ,berichte4 ,wien1 #ahgc4 ,,vachon1 ,m4--,les arts et les industries du papier4 ,france1 #ahga-ahid4 ,,valenta1 ,e4--,das ,papier1 seine ,herstellung1 ,eigenschaften1 ,prfung4 #aijd4 ,,wanderley1 ,g4--,die ,papierfabrikation und ,papierfabrikanlage4 ,leipzig1 #ahgf4 ,,watt1 ,a4--,the ,art of ,paper-making1 with the ,recovery of ,soda from ,waste ,liquors4 ,london1 sm4 #ho1 #ahij4 ,,weber1 ,r4--,papier-,industrie4 ,vienna ,universal ,exhibition1 #ahgc4 ,,wehrs1 ,g4 ,f4--,vom ,papier1 den vor der ,erfindung desselben blich gewesenen ,schreibmassen und sonstigen ,schreibmaterialien4 ,halle1 #ho1 #aghi4 ,,winkler1 ,o4--,der ,papierkenner4 #ahhg4 ,,paper1 ,,special ,,kinds4 ,,and,s1 ,l4 ,e4--,papier-,spezialitten1 praktische ,anleitung zur ,herstellung4 #ahif4 ,,and,s1 ,l4 ,e4--,treatment of ,paper for ,special ,purposes4 ,translated from ,german4 #aijg4 ,,and,s1 ,l4 ,e4--,die ,fabrikation der ,papiermach und ,papierstoff-,waren4 ,leipzig1 #aijj4 ,,and,s1 ,l4 ,e4--,blattmetalle1 ,bronzen und ,metallpapiere1 deren ,herstellung und ,anwendung4 ,wien1 sm4 #ho1 #aijb4 ,,boeck1 ,j4 ,p4--,die ,marmorirkunst fr ,buchbindereien1 ,buntpapierfabriken4 ,wien1 sm4 #ho1 #ahhj4 ,,briquet1 ,m4--,de quelques industries nouvelles dont le papier est la base4 ,genve1 #ahhe4 ,,exner1 ,w4 ,f4--,tapeten- und ,buntpapier-,industrie4 ,paris ,univ4 ,exhibition1 #ahfg4 ,austrian ,comm4 ,berichte4 ,heft #h4 #ahfg4 ,,exner1 ,w4 ,f4--,tapeten- und ,buntpapier4 ,vienna ,universal ,exhibition1 #ahgc4 ,officieller ,ausstellungs-,bericht4 ,heft #ec4 #ho1 #ahgc4 ,,fichtenberg4--,nouveau manuel complet du fabricant de papiers de fantaisie1 papiers marbrs1 etc4 ,paris1 #aho1 #aheb4 ,,herring1 ,r4--,guide to ,varieties and ,value of ,paper4 #ahfj4 ,,hofmann1 ,a4 ,w4--,report on ,vegetable ,parchment 7,gaine's ,patent1 ,no4 #bhcd of #ahec74 ,london1 #ho1 #aheh4 ,,kaeppelin1 ,d4--,fabrication des papiers peints4 ,lacroix ,e41 tudes sur l'exposition de #ahfg4 ,vol4 #a4 #ho1 #ahfg4 ,,kaeppelin1 ,d4--,fabrication des papiers peints4 #ahha4 ,,lindsey1 ,g4--,pens and ,papiermach4 ,bevan1 ,g4 ,p41 ,brit4 ,manufacturing ,industries 7iii474 #abo1 #ahgf4 ,,morton1 ,g4 ,h4--,the ,history of ,paper-hangings1 with ,review of other ,modes of ,mural ,decoration4 ,liverpool1 #ho1 #ahge4 ,,sanborn1 ,k4--,old ,time ,wall ,papers4 #aije4 ,,schmidt1 ,c4 ,h4--,die ,benutzung des ,papiermach4 ,weimar1 #abo1 #ahdg4 ,,schmidt1 ,c4 ,h4--,die ,papier-,tapetenfabrikation4 #cte ,aufl4 ,weimar1 #abo1 #ahef4 ,,schmidt1 ,c4 ,h4--,the ,book of ,papiermach and ,japanning4 ,london1 #ahej4 ,,seeman1 ,,th4--,die ,tapete1 ihre aesthetische ,bedeutung u4 ,techn4 ,darstellung1 sowie kurze ,beschreibung der ,buntpapierfabrik4 #ahhb4 ,,silcox4--,manufacture of ,paper ,barrels4 ,vienna ,exhibition1 #ahgc4 ,u4,s4,a4 ,reports1 ii4 ,,smee1 ,a4--,report on ,vegetable ,parchment 7,gaine's ,patent1 ,no4 #bhcd of #ahec74 ,london1 #ho1 #aheh4 ,,thon1 ,c4 ,f4 ,g4--,der ,fabrikant bunter ,papiere1 #cte ,aufl4 ,weimar1 #abo1 #ahdd4 ,,weichelt1 ,a4--,buntpapier-,fabrikation4 ,berlin1 #ho1 #aijc4 ,,whiting ,,paper ,,co4--,how ,paper is ,made4 ,holyoke1 ,mass41 #cbo1 #ahic4 ,,winzer1 ,a4--,die ,bereitung und ,benutzung der ,papiermach und hnlicher ,kompositionen1 #cte ,aufl4 ,weimar1 #abo1 #ahhd4 ,ditto1 #dth edition1 #aijg4 ,,woolnough1 ,c4 ,w4--,the ,whole ,art of ,marbling1 as applied to ,paper1 ,book ,edges1 etc4 ,london1 #ho1 #ahha4 ,,wyatt1 ,,sir ,m4 ,d4--,report on ,paper-hangings4 ,paris ,univ4 ,exhibition1 #ahfg4 ,brit4 ,comm4 ,report1 ,vol4 ,,ii4 #ho1 #ahfg4 ,,statistics ,,and ,,various4 ,,akesson4--,lexikon der ,papier-,industrie4 ,deutsch-,englisch-,franzsisch1 #bte ,aufl4 #aije4 ,,archer1 ,t4 ,c4--,british ,manufacturing ,industries4 ,vol4 #ae4 ,industrial ,statistics4 ,london4 ,,barth1 ,e4--,arbeitsregeln fr ,fabriken mit besonderer ,bercksichtigung von ,papierfabriken4 ,karlsruhe1 #ahig4 ,,baudisch1 ,j4--,einige ins ,papierfach schlagende ,berechnungen4 ,biberach1 #ahic4 ,,dyson4--,mosely ,commission ,report4 ,manchester1 #aijc4 ,,ermel4--,rapport sur le matriel et les procds de la papeterie1 etc4 ,paris ,univ4 ,exhibition1 #ahgh4 ,rapports4 ,classe #fj4 #ho1 #ahha4 ,,foreign ,,office1 ,no4 #d 7#ahga74--,reports on the ,manufacture of ,paper in ,japan4 ,london1 fol41 #ahga4 ,,geyer1 ,a4--,registry of ,water-marks and ,trade-marks4 ,compiled from the ,american ,paper ,trade 7#bnd edition74 ,new ,york1 #ahih4 ,ditto1 #eth edition1 #aijc4 ,,gratiot1 ,a4--,description de la papeterie d',essonnes1 ,london ,international ,exhibition of #ahea1 ,prospectuses of ,exhibitors4 ,vol4 #b4 #ho1 #ahea4 ,,krawany1 ,f4--,warte der ,papier-,halbstoff- und ,pappenfabriken ,oesterreich-,ungarns4 #aije4 ,,landgraf1 ,j4--,papier-,holzschliff und seine ,zollpolitische ,wrdigung4 ,mannheim4 ,,lockwood ,,co4--,american ,dictionary of ,printing and ,bookmaking4 ,new ,york1 #ahie4 ,,ludwig1 ,g4--,trockengehalts-,tabellen4 ,pirna1 #ahig4 ,,macnaughton1 ,j4--,factory ,book-keeping for ,paper ,mills4 #aijj4 ,,mahrlen4--,papierfabrikation1 im ,knigr4 ,wrttemberg 7im ,jahre #ahfj74 ,stuttgart1 #ho1 #ahfa4 ,,marr1 ,d4--,kosten der ,betriebskrfte bei #a-bd stndiger ,arbeitszeit tglich und unter ,bercksichtigung des ,aufwandes fr die ,heizung4 ,mnchen u4 ,berlin4 ,,melnikoff1 ,n4--,lehrbuch der ,papier-,holzschliff1 ,zellstoff und ,pappenfabrikation4 ,petersburg1 #aije4 ,,melnikoff1 ,n4--,kleines ,handbuch ,papierfabrikation4 ,petersburg1 #aijf4 ,,melnikoff1 ,n4--,geschichte1 ,statistik u4 ,literatur der ,papierindustrie nebst russischen ,wasserzeichen4 ,petersburg1 #aijf4 ,,munsell1 ,j4--,chronology of ,paper-making4 ,albany1 #ho1 #aheg4 ,ditto1 #dth edition1 #ahgj4 ,,munsell1 ,j4--,chronology of the ,origin and ,progress of ,paper and ,paper-making4 ,albany1 #ahgf4 ,,munsell1 ,j4--,observations ,illustrative of the ,operation of the ,duties on ,paper4 ,london1 #ho1 #ahcf4 ,,munsell1 ,j4--,matriel et procds de la papeterie1 etc41 #ahhi4 ,rapports du ,jury4 ,classe #eh4 #ho1 #ahhi4 ,,paris ,,univ4 ,,exhibition4--,papiers peints1 #ahhi4 ,rapports du ,jury4 ,classe #ba4 #ho1 #ahia4 ,,passerat1 ,a4 ,l4--,barme complet pour papeteries4 ,paris4 ,,patents4--,patent ,abridgments4 ,class #if4 ,patent ,office ,abstracts on ,paper-making4 ,from #ahee to date4 ,,roulhac4--,papeterie4 ,paris ,univ4 ,exhibition1 #ahfg4 ,rapports du ,jury4 ,classe #g1 sect4 #a4 #ho1 #ahfh4 ,,sampson1 ,j4 ,t4--,paper-staining4 ,mansion ,house ,committee4 ,artisans' ,reports1 ,paris ,exhibition4 #ho1 #ahhi4 ,,treasury4--,report of the ,excise ,commission4 #ahce4 ,,vogel1 ,k4--,papierindustrie1 etc41 ,auf der ,weltausstellung in ,chicago4 ,chicago ,exhibition1 #ahic4 ,austrian ,central ,committee4 ,officieller ,bericht4 ,heft iv4 #ho1 #ahid4 ,,voigt1 ,g4--,papiergewichtstabellen4 ,merseburg1 #ahid4 ,,ward1 ,,sir ,w4--,report on ,german ,paper-making ,industry4 ,parliamentary ,paper1 #aije4 ,,water-,,marks4--,water-marks and ,trade-marks ,registry 7#bnd ed474 ,new ,york1 #afo1 #ahih4 ,,wood ,,pulp ,,and ,,pulp ,,wood4 ,,british ,,and ,,colonial ,,printer4--,history of ,wood ,pulp4 ,vol4 #h4 #ahhb4 ,,dunbar4--,wood ,pulp and ,wood ,pulp ,papers4 ,,fittica1 ,,dr4 ,f4--,geschichte der ,sulfitzellstoff-,fabrikation4 ,leipzig1 #aija4 ,,fittica1 ,,dr4 ,f4--,forestry and ,forest ,products4 ,edinburgh ,forestry ,exhibition4 #ahhd4 ,,gottstein4--,holzzellstoff in seiner ,anwendung fr die ,papier- und ,textil-,industrie und die bei seiner ,herstellung entstehenden ,abwsser4 #aijd4 ,,griffin1 ,m4 ,l4--,sulphite ,processes4 ,american ,society ,c4 ,e4 #dag4 #ahhi4 ,,harper1 ,w4--,utilisation of ,wood ,waste by ,distillation4 ,u4,s4,a41 #aijg4 ,,harpf1 ,a4--,die ,erzeugung von ,holzschliff und ,zellstoff4 ,wien1 #aija4 ,,harpf1 ,a4--,flssiges ,schwefeldioxyd4 ,stuttgart1 #aija4 ,,hubbard4--,utilisation of ,wood ,waste4 #aijb4 ,,johnson1 ,g4--,wood ,pulp of ,canada4 #aijb-jh4 ,yearly4 ,,michaelis1 ,o4 ,e4--,lime ,sulphite ,fibre ,manufacture in the ,united ,states4 ,with ,remarks on the ,chemistry of the ,processes1 by ,m4 ,l4 ,griffin 7excerpt74 ,new ,york1 #ho1 #ahhi4 ,,phillips1 ,s4 ,c4--,uses of ,wood ,pulp4 #aijd4 ,,rosenheim1 ,g4 ,m4--,die ,holzcellulose4 ,berlin1 #ahgh4 ,,schubert1 ,m4--,die ,holzstoff oder ,holzschliff-,fabrikation4 #ahih4 ,,schubert1 ,m4--,die ,cellulosefabrikation 7,zellstofffabrikation74 ,praktisches ,handbuch fr ,papier- u4 ,cellulosetechniker4 #aijf4 ,,sindall1 ,r4 ,w4--,the ,sampling of ,wood ,pulp4 ,london1 #ho1 #aija4 ,,veitch1 ,l4 ,p4--,chemical ,methods for ,utilising ,wood4 ,u4,s4,a4 ,department of ,agriculture4 #aijg4 ,,veitch1 ,l4 ,p4--,wood ,pulp1 ,uses of4 ,u4,s4,a4 ,consular ,reports1 vol4 xix4 99 99 99 99 99 ,,banks ,,and ,,crate4--,pulpwood ,problems4 ,letters to the ,globe1 ,toronto1 ,canada4 #aijg4 ,,gamble1 ,j4--,indian ,timbers4 ,,graves4--,the ,woodsman's ,handbook4 ,u4,s4,a4 ,,pinchott1 ,g4--,forestry ,primer4 ,u4,s4,a41 #aijj4 ,,pinchott1 ,g4--,the ,adirondack ,spruce4 ,u4,s4,a4 ,,rattray1 ,j41 ,,and ,,mill1 ,h4 ,r4--,forestry and ,forestry ,products4 ,edinburgh1 #ahhe4 ,,schlich4--,forestry ,manual4 99 99 99 99 99 ,some more or less interesting articles on ,paper will be found in the following encyclopdias1 etc43-- ,,date4 #agch4 ,chambers's ,encyclopdia4 #ageg4 ,barrow4 ,dictionary of ,arts4 #agei4 ,new4 ,universal ,history of ,arts4 #aggj4 ,royal ,dictionary of ,arts4 #aghh4 ,howard4 ,a ,royal ,encyclopdia4 #ahjf4 ,gregory4 ,a ,dictionary of ,arts and ,sciences4 #ahjg4 ,encyclopdia ,perthensis4 #ahji4 ,nicholson4 ,the ,british ,encyclopdia4 #ahac4 ,martin4 ,circle of the ,mechanical ,arts4 #ahac4 ,pantologia4 #ahai4 ,rees' ,cyclopdia4 #ahba4 ,encyclopdia ,londoniensis4 #ahbg4 ,jamieson's ,dictionary4 #ahbh4 ,oxford ,encyclopdia4 #ahbi4 ,the ,london ,encyclopdia4 #ahcj4 ,edinburgh ,encyclopdia4 #ahcc4 ,phillip's ,dictionary of ,arts4 #ahce4 ,partington4 ,british ,cyclopdia4 #ahcf4 ,archologia1 vol4 xxvi4 #ahcf4 ,barlow4 ,encyclopdia of ,arts4 #ahdj4 ,the ,penny ,encyclopdia4 #ahde4 ,encyclopdia ,metropolitana4 #ahdh4 ,useful ,arts of ,great ,britain4 ,s4,p4,c4,k #ahea4 ,knight's ,cyclopdia of ,industry4 #ahee4 ,appleton's ,dictionary of ,mechanics4 #ahfj4 ,hebert4 ,mechanic's ,encyclopdia4 #ahfa4 ,knight's ,english ,cyclopdia4 #ahfa4 ,new ,american ,cyclopdia4 #ahff4 ,tomlinson's ,dictionary of ,arts4 #ahga4 ,yeats4 ,the ,technical ,history of ,commerce4 #ahgd4 ,clarke's ,practical ,magazine4 #ahge4 ,ure's ,dictionary of ,arts4 #ahge4 ,globe ,cyclopdia4 #ahgf4 ,american ,mechanical ,dictionary4 #ahgg4 ,johnson's ,universal ,cyclopdia4 #ahhj4 ,wylde4 ,industries of the ,world4 #ahhb4 ,spon's ,encyclopdia of ,manufactures4 #ahhf4 ,encyclopdia ,britannica4 #ahhi4 ,chambers's ,encyclopdia4 #ahhi4 ,blaikie4 ,modern ,cyclopdia4 #ahij4 ,popular ,encyclopdia4 #ahib4 ,spon's ,workshop ,receipts4 #aijc4 ,gilman4 ,international ,encyclopdia4 #aijd4 ,encyclopdia ,americana4 #aijd4 ,tweney's ,technological ,dictionary4 ,,newspapers4 ,england4 ,papermaker and ,british ,paper ,trade ,journal4 ,s4 ,c4 ,phillips1 ,london4 ,papermakers' ,circular4 ,dean ,son1 ,london4 ,papermakers' ,monthly ,journal4 ,marchant1 ,singer ,co41 ,london4 ,paper ,box and ,bag ,maker4 ,s4 ,c4 ,phillips1 ,london4 ,papermaking4 ,london4 ,the ,paper and ,printing ,trades' ,journal4 ,london4 ,world's ,paper ,trade ,review4 ,w4 ,j4 ,stonhill1 ,london4 ,canada4 ,pulp and ,paper ,magazine4 ,biggar-,wilson1 ,ltd41 ,toronto4 ,united ,states of ,america4 ,american ,bookmaker4 ,howard ,lockwood ,co41 ,new ,york4 ,the ,paper ,trade4 ,chicago4 ,the ,stationer4 ,howard ,lockwood ,co41 ,new ,york4 ,paper ,mill and ,wood ,pulp ,news4 ,l4 ,d4 ,post ,co41 ,new ,york4 ,paper ,trade ,journal4 ,howard ,lockwood ,co41 ,new ,york4 ,the ,paper ,world4 ,c4 ,w4 ,bryan ,co41 ,holyoke1 ,mass4 ,france4 ,bulletin ,journal des ,fabricants de ,papier4 ,paris4 ,journal des ,papetiers4 ,m4 ,edmond ,rousset1 ,paris4 ,le ,moniteur de la ,papeterie ,franaise4 ,paris4 ,la ,papeterie4 ,paris4 ,la ,revue de la ,papeterie ,franaise et trangre4 ,m4 ,edmond ,rousset1 ,paris4 ,le ,papier4 ,h4 ,everling1 ,paris4 ,germany4 ,centralblatt fr die sterreichisch-,ungarische ,papierindustrie4 ,adolf ,hladufka1 ,wien4 ,der ,papierfabrikant4 ,otto ,elsner1 ,berlin4 ,der ,papier-,markt4 ,carl ,dobler1 ,frankfurt a4 ,main4 ,deutsche ,papier- und ,schreibwarenzeitung4 ,s4 ,richter1 ,berlin4 ,die ,postkarte4 ,gustav ,fahrig1 ,leipzig4 ,export-,journal4 ,g4 ,hedeler1 ,leipzig4 ,holzstoff-,zeitung4 ,camillo ,drache1 ,dresden4 ,papierhndler ,zeitung fr sterreich-,ungarn4 ,wien4 ,papier-,industrie4 ,berlin4 ,papier- und ,schreibwaren-,zeitung4 ,wien4 ,papier-,zeitung4 ,c4 ,hofmann1 ,berlin4 ,schweizer ,graphischer ,central-,anzeiger4 ,h4 ,keller1 ,luzern4 ,wochenblatt fr ,papierfabrikation4 ,guntter-,staib ,biberach 7,wrtt74 ,wochenschrift fr den ,papier- und ,schreibwarenhandel4 ,dr4 ,h4 ,hirschberg1 ,berlin4 ,,analysis1 ,,technology4 ,,beadle ,,and ,,stevens4--,blotting paper1 nature of absorbency4 #aije4 ,,winkler4--,estimation of ,moisture in ,wood-pulp4 #aijb4 ,translated by ,dr4 ,h4 ,p4 ,stevens4 ,,hauptversammlung4--,published annually by the ,verein der ,zellstoff- und ,papier-,chemiker4 ,berlin1 #aijg et4 ,,fibres1 etc4 ,,dodge1 ,c4 ,r4--,catalogue of useful ,fibre-plants of the ,world4 ,report ,no4 #i4 ,dept4 of ,agriculture4 ,u4,s4,a41 #ahig4 ,,duchesne1 ,e4 ,a4--,rpertoire des plantes utiles et des plantes vnneuses du globe1 etc4 ,bruxelles1 #ahdf4 ,,gabalde1 ,b4--,essai sur le bananier et ses applications la fabrication de papier4 #ahdc4 ,,montessus ,,de ,,ballore4--,alfa et papier d',alfa4 #aijh4 ,,pecheux4--,les textiles1 les tissus1 le papier4 #f pp4 ,paris1 #aijg4 ,,renouard4--tudes sur les fibres textiles4 ,paris4 ,,renouard4--,les fibres textiles de l',algrie4 ,paris4 ,,riviere1 ,,auguste ,,et ,,charles4--,les ,bambous4 ,socit d',acclimatation4 ,paris4 ,,richmond1 ,g4 ,f4--,philippine ,fibres and ,fibrous ,substances4 ,manila1 ,bureau of ,printing1 #aijf4 ,,historical4 ,,briquet1 ,c4 ,m4--,recherches sur les premiers ,papiers employs du ,xe au ,,xive sicle4 pp4 #gg4 ,paris1 #ahhf4 ,,briquet1 ,c4 ,m4--,de la valeur des ,filigranes du ,papier comme moyen de dterminer l'ge de documents4 pp4 #ac4 ,genve1 #ahib4 ,,briquet1 ,c4 ,m4--,la ,lgende palographique du ,papier de ,coton4 pp4 #ah4 ,genve1 #ahhd4 ,,briquet1 ,c4 ,m4--,lettre sur les ,papiers usits en ,sicile l'occasion de deux manuscrits en papier dit le coton4 #af pp4 ,palermo1 #ahib4 ,,desmarest1 ,n4--,art de la ,papeterie4 ,paris1 #ahgi4 ,,delon1 ,c4--,histoire d'un livre4 ,paris1 #ahgi4 ,,didot1 ,a4 ,f4--,le centenaire de la ,machine ,papier continu4 pp4 #gi4 ,paris1 #aijj4 ,,dickinson1 ,j4--,dickinson's ,paper ,mills4 ,calcutta1 #ahhd4 ,,girard1 ,a4--,le ,papier4 ,ses anctres4 ,son histoire4 ,lille1 #ahib4 ,,julien1 ,s4--,description des procds chinois pour la fabrication du papier4 ,traduit de l'ouvrage chinois par ,thien-,kong-,kha-,we4 #ahdj4 ,,kay1 ,j4--,paper1 its history4 pp4 #ajj4 ,london1 #ahic4 ,,lempertz1 ,h4--,beitrge zur ,geschichte des ,leinen-,papiers4 ,kln1 #ahia4 ,,paper ,,manufacture4 ,,bory1 ,p4--,les ,mtamorphoses d'un ,chiffon4 ,abbeville1 #ahig4 ,,chabrol1 ,l4--,la ,rglementation du ,travail dans l'industrie du papier4 pp4 #afh4 ,paris1 #aija4 ,,demuth1 ,f4--,die ,papier-,fabrikation4 #aijc4 ,,demuth1 ,f4--,die ,strungen im deutschen ,wirtschaftsleben #aijj4 ,leipzig1 #aijc4 ,,limoge4--,cercles d'tudes commerciales1 ,le ,papier4 pp4 #adj4 ,limoge1 #ahib4 ,,paper1 ,,special ,,kinds4 ,,spalding ,,and ,,hodge4--,printing papers2 a handbook4 ,london1 #aije4 ,,statistics1 etc4 ,,beadle1 ,c4--,development of ,water-marking4 ,london1 #aijf 7,society of ,arts74 ,,dumercy4--,bibliographie de la ,papeterie4 pp4 #bh4 ,bruxelles1 #ahhh4 ,,bruce1 ,h4--,gladstone and ,paper ,duties4 ,edinburgh1 #ahhe4 ,,ellis1 ,j4 ,b4--,hints for the ,paper ,warehouse4 ,leeds1 #ahhg4 ,,webster1 ,j4--,synopsis of ,sizes of ,paper4 ,southport1 #ahhi4 ,,whitson1 ,w4--,the ,concise ,paper ,calculator4 ,edinburgh1 #aijc4 ,,wood ,,pulp1 etc4 ,,dropisch1 ,b4--,holzstoff und ,holzcellulose4 ,weimar1 #ahgi4 ,,index ,acid dyes1 #bja in papers1 #bci size1 #agj ,agave1 #dj ,alum1 #afg1 #afh ,aniline dyes1 #bja sulphate1 #aba ,animal size1 #fc1 #afd ,antichlors1 #afc ,art paper1 #adb imitation1 #ade testing1 #adg ,asbestos1 #agd ,ash in paper1 #aga ,backwater1 #abj1 #bje ,bagasse1 #da ,bamboo1 #dc ,barker1 #ig ,beating engines1 #ahf patents1 #aib power consumed1 #aia ,beating1 conditions of1 #aig early methods of1 #agf experiments in1 #agi process of1 #eh1 #age ,bibliography1 #bec ,bisulphite of lime1 #aei ,bleaching1 #eg1 #hc powder1 #afa ,blue prints1 #adj ,board machine1 #acb1 #ace ,boards1 manufacture of1 #aca duplex1 #acb1 #acd ,book papers1 quality of1 #bdf ,books1 decay of1 #bcg ,brown papers1 #abg ,carbonic acid recorder1 #bae ,casein1 #afe1 #bce ,caustic soda1 #ha1 #aee ,cellulose1 #ba derivatives of1 #bi hydrolysis of1 #bg1 #bbi oxidation of1 #bh percentage of1 in plants1 #bc properties of1 #bf ,chemical residues in paper1 #bch wood pulp1 #ajd ,chemicals1 #aec ,china clay1 #aag1 #aej1 #aga1 #bjd1 #bcd ,coal consumption1 #bad ,coated paper1 #adb ,cold ground pulp1 #ajj ,colophony1 #afi ,colour of paper1 fading of1 #bjc1 #bda matching1 #bje unevenness of1 #bjc ,colouring of paper pulp1 #aii analysis of1 #bjf ,cotton1 #bb1 #fi ,cyanotype papers1 #adj ,cylinder machine1 #aca ,density of paper1 #aha ,deterioration of paper1 #bbh1 #bdf ,digesters1 #eb1 #hi1 #aji ,dilution tables1 #aeg1 #afc ,duplex boards1 #acd ,dyeing of paper1 #aii ,eibel patent1 #bbc ,electrical power1 #bai ,electrolytic bleaching1 #eg ,engine sizing1 #aag1 #afg ,esparto1 #gb bleaching of1 #hc composition of1 #gc test for1 in papers1 #hg yield of1 #gg ,evaporation apparatus1 #gf1 #gi tables1 #ha ,featherweight papers1 #bcb ,fibres for paper-making1 #ch examination of1 #dc reagents for staining1 #ga ,flax1 #dj ,fourdrinier machine1 early1 #af ,french chalk1 #agc ,gas producer1 #bah ,gelatine1 #fc1 #afd1 #bcg ,glue1 #acg1 #adb1 #bce ,grinders1 #ajj ,history of paper1 #a ,hoernle1 #g ,hollander1 #af1 #ei1 #agf1 #ahe ,hot ground pulp1 #ajj ,imitation art paper1 #ade1 #bce ,kraft paper1 #abi parchment1 #acg ,improvements in paper-making1 #bad ,iron in paper1 #bbi ,kraft papers1 #abh ,laid papers1 #ff ,lime1 #eb1 #aeg bisulphite1 #aei sulphate1 #agc ,linen fibre1 #gj ,loading1 #aga ,m4 ,g4 caps1 #acj ,machinery1 #bad1 #bbd ,manila paper1 #abg ,mechanical pulp1 #ie detection of1 #aba ,metanil yellow1 #abb ,middles1 #acd ,mitscherlich pulp1 #ajg ,moisture1 influence of1 #bdc ,multiple effect evaporation1 #gi ,neutral size1 #afi ,newspaper1 #aaf1 #bae ,output of a paper machine1 #abb ,paper1 art1 #adb ash in1 #aga brown1 #abg bulk of1 #bca chemical residues in1 #bch clay in1 #bcd colour of1 #aii1 #bda colour in1 analysis of1 #bjg deterioration of1 #bbi fibres for1 #ch history of1 #a1 #e iron in1 #bci permanence of1 #bcj rags used for1 #dg sizing of1 #fc special kinds of1 #acg standards of quality1 #bdf strength1 of1 #ahd1 #bca surface of1 #bcc volume composition of1 #bcc ,paper machine1 early1 #af output of1 #abb ,papier-mach1 #aej ,papyrus1 #b1 #db ,paraffin paper1 #adh ,parchment1 #d paper1 #acg ,peat1 #da ,phloroglucine1 #aba ,pigments1 #aii ,porion evaporator1 #gf ,presse-pte1 #hf ,prussian blue1 #bjj ,rag paper1 manufacture of1 #dg origin of1 #e ,rags1 bleaching1 #ee boiling1 #ea classification1 #dh sorting1 #dh ,ramie1 #dj ,records1 early1 #a ,recovered ash1 #aeh ,recovery processes1 #gh1 #aac ,refiners1 #ij ,rope browns1 #abg ,rosin size1 #aag1 #afi1 #bcf ,screens1 #ajb ,sealings1 #abi ,shrinkage of paper1 #aha ,sizing of paper1 #fc1 #aag1 #afg ,society of ,arts1 #bdf ,soda1 #aec ,soda pulp1 #ajg1 #aac recovery1 #gh silicate of1 #aff1 #aga ,softening of water1 #baf ,spent liquors1 #gh1 #aac ,staining reagents for fibres1 #ga ,standards of quality1 #bdf1 #bdh1 #bej ,starch1 #aff1 #bcg ,stationery ,office1 #bdh ,stone beater rolls1 #ahi ,straw1 #hh ,sulphate pulp1 #ajg ,sulphite pulp1 #ajg ,sulphites1 #aei1 #afc ,supercalender1 #fe ,superheated steam1 #bah ,tinfoil paper1 #adh ,transfer paper1 #adi ,ultramarine1 #aii ,volume composition of paper1 #bcc ,vulcanised fibre1 #aci ,water softening1 #baf ,watermarks1 #fg ,wavy edges1 #bdc ,waxed paper1 #adg ,wet press machine1 #ajc ,wiesner1 #f ,willesden paper1 #aci ,wood1 #bb pulp1 #ie chemical1 #ajd mechanical1 #ie soda1 #ajg1 #aac sulphite1 #ajg ,wove papers1 #ff ,wrappers1 #abg ,,bradbury1 ,,agnew1 ,,co4 ,,ld41 ,,printers1 ,,london ,,and ,,tonbridge4 ,,van ,,nostrand',s ,westminster ,series ,bound in uniform style4 ,fully ,illustrated4 ,price #bjj net each4 ,the ,volumes in the ,westminster ,series have been designed to meet the growing demand for books on practical subjects2 to bring within the ken of the non-technical reader an accurate knowledge of manufacturing processes and the practical application of modern science to industries4 ,each volume is written by an expert to the end that practical readers and all who are engaged in the numerous allied branches of the engineering and technical trades may have reliable works of reference4 ,the series provides for a class not hitherto reached in published works4 ,the volumes can be easily read by the general public1 and make excellent handbooks at a moderate price for the student4 ,the series is well suited to public libraries and will be found valuable for libraries in engineering shops and factories4 ,d4 ,,van ,,nostrand ,,company ,publishers and ,booksellers #bc1 ,murray and #bg1 ,warren ,streets1 ,new ,york4 ,coal4 ,by ,,james ,,tonge1 ,m4,i4,m4,e41 ,f4,g4,s41 etc4 7,lecturer on ,mining at ,victoria ,university1 ,manchester74 ,with #df ,illustrations1 many of them showing the ,fossils found in the ,coal ,measures4 ,,list ,,of ,,contents3 ,history4 ,occurrence4 ,mode of ,formation of ,coal ,seams4 ,fossils of the ,coal ,measures4 ,botany of the ,coal-,measure ,plants4 ,coalfields of the ,british ,isles4 ,foreign ,coalfields4 ,the ,classification of ,coals4 ,the ,valuation of ,coal4 ,foreign ,coals and their ,values4 ,uses of ,coal4 ,the ,production of ,heat from ,coal4 ,waste of ,coal4 ,the ,preparation of ,coal for the ,market4 ,coaling ,stations of the ,world4 ,index4 ,this book on a momentous subject is provided for the general reader who wishes accurate knowledge of ,coal1 its origin1 position and extent1 and its economical utilization and application4 ,iron and ,steel4 ,by ,j4 ,h4 ,,stansbie1 ,b4,sc4 7,lond471 ,f4,i4,c4 ,with #hf ,illustrations4 ,,list ,,of ,,contents3 ,introductory4 ,iron ,ores4 ,combustible and other materials used in ,iron and ,steel ,manufacture4 ,primitive ,methods of ,iron and ,steel ,production4 ,pig ,iron and its ,manufacture4 ,the ,refining of ,pig ,iron in ,small ,charges4 ,crucible and ,weld ,steel4 ,the ,bessemer ,process4 ,the ,open ,hearth ,process4 ,mechanical ,treatment of ,iron and ,steel4 ,physical and ,mechanical ,properties of ,iron and ,steel4 ,iron and ,steel under the ,microscope4 ,heat ,treatment of ,iron and ,steel4 ,electric ,smelting4 ,special ,steels4 ,index4 ,the aim of this book is to give a comprehensive view of the modern aspects of iron and steel1 together with a sufficient account of its history to enable the reader to follow its march of progress4 ,the methods of producing varieties of the metal suitable to the requirements of the engineer1 foundryman and mechanician are described so that the worker may learn the history of the material he is handling4 ,natural ,sources of ,power4 ,by ,robert ,s4 ,ball1 ,b4,sc41 ,a4,m4,inst4,c4,e4 ,with #ajd ,diagrams and ,illustrations4 ,,contents3 ,preface4 ,units with ,metric ,equivalents and ,abbreviations4 ,length and ,distance4 ,surface and ,area4 ,volumes4 ,weights or ,measures4 ,pressures4 ,linear ,velocities1 ,angular ,velocities4 ,acceleration4 ,energy4 ,power4 ,introductory ,water ,power and ,methods of ,measuring4 ,application of ,water ,power to the ,propulsion of ,machinery4 ,the ,hydraulic ,turbine4 ,various ,types of ,turbine4 ,construction of ,water ,power ,plants4 ,water ,power ,installations4 ,the ,regulation of ,turbines4 ,wind ,pressure1 ,velocity1 and ,methods of ,measuring4 ,the ,application of ,wind ,power to ,industry4 ,the ,modern ,windmill4 ,constructional ,details4 ,power of ,modern ,windmills4 ,appendices ,a1 ,b1 ,c4 ,index4 ,two departments of ,engineering and their applications to industry form the subject of this volume3 the natural sources of water and wind power which supply mechanical energy without any intermediate stage of transformation4 ,most people will be surprised at the extent to which these natural power producers are used4 ,the widespread application of water power is generally known1 but it is interesting to learn that the demand for windmills was never so great as it is to-day1 and there are signs of abnormal expansion in the direction of their useful application in the great agricultural countries of the world4 ,though primarily of importance to the engineer1 this work will be of great interest to every manufacturer who in economizing his means of power production can take the natural forces that lie to his hand and harness them in his service4 ,the author is the son of ,sir ,robert ,ball1 the eminent mathematician and astronomer4 ,liquid and ,gaseous ,fuels1 and the ,part they play in ,modern ,power ,production4 ,by ,professor ,,vivian ,b4 ,,lewes1 ,f4,i4,c41 ,f4,c4,s41 ,prof4 of ,chemistry1 ,royal ,naval ,college1 ,greenwich4 ,with #ed ,illustrations4 ,,list ,,of ,,contents3 ,lavoisier's ,discovery of the ,nature of ,combustion1 etc4 ,the ,cycle of ,animal and ,vegetable ,life4 ,method of determining ,calorific ,value4 ,the ,discovery of ,petroleum in ,america4 ,oil ,lamps1 etc4 ,the ,history of ,coal ,gas4 ,calorific ,value of ,coal ,gas and its ,constituents4 ,the ,history of ,water ,gas4 ,incomplete ,combustion4 ,comparison of the ,thermal ,values of our ,fuels1 etc4 ,appendix4 ,bibliography4 ,index4 ,the subject of this book has1 during the last decade1 assumed such importance that it is hoped this account of the history and development of the use of various forms of combustible liquids and gases for the generation of energy may do some service in its advancement4 ,electric ,power and ,traction4 ,by ,f4 ,h4 ,,davies1 ,a4,m4,i4,e4,e4 ,with #ff ,illustrations4 ,,list ,,of ,,contents3 ,introduction4 ,the ,generation and ,distribution of ,power4 ,the ,electric ,motor4 ,the ,application of ,electric ,power4 ,electric ,power in ,collieries4 ,electric ,power in ,engineering ,workshops4 ,electric ,power in ,textile ,factories4 ,electric ,power in the ,printing ,trade4 ,electric ,power at ,sea4 ,electric ,power on ,canals4 ,electric ,traction4 ,the ,overhead ,system and ,track ,work4 ,the ,conduit ,system4 ,the ,surface ,contact ,system4 ,car ,building and ,equipment4 ,electric ,railways4 ,glossary4 ,index4 ,the majority of the allied trades that cluster round the business of electrical engineering are connected in some way or other with its power and traction branches4 ,to members of such trades and callings1 to whom some knowledge of applied electrical engineering is desirable if not strictly essential1 the book is particularly intended to appeal4 ,it deals almost entirely with practical matters1 and enters to some extent into those commercial considerations which in the long run must overrule all others4 ,town ,gas and its ,uses for the ,production of ,light1 ,heat1 and ,motive ,power4 ,by ,w4 ,h4 ,y4 ,,webber1 ,c4,e4 ,with #ga ,illustrations4 ,,list ,,of ,,contents3 ,the ,nature and ,properties of ,town ,gas4 ,the ,history and ,manufacture of ,town ,gas4 ,the ,by-,products of ,coal ,gas ,manufacture4 ,gas ,lights and ,lighting4 ,practical ,gas ,lighting4 ,the ,cost of ,gas ,lighting4 ,heating and ,warming by ,gas4 ,cooking by ,gas4 ,the ,healthfulness and ,safety of ,gas in all its uses4 ,town ,gas for ,power ,generation1 including ,private ,electricity ,supply4 ,the ,legal ,relations of ,gas ,suppliers1 ,consumers1 and the ,public4 ,index4 ,the country1 as opposed to the town1 has been defined as the parts beyond the gas lamps4 ,this book provides accurate knowledge regarding the manufacture and supply of town gas and its uses for domestic and industrial purposes4 ,few people realize the extent to which this great industry can be utilized4 ,the author has produced a volume which will instruct and interest the generally well informed but not technically instructed reader4 ,electro-,metallurgy4 ,by ,j4 ,b4 ,c4 ,,kershaw1 ,f4,i4,c4 ,with #fa ,illustrations4 ,,contents3 ,introduction and ,historical ,survey4 ,aluminium4 ,production4 ,details of ,processes and ,works4 ,costs4 ,utilization4 ,future of the ,metal4 ,bullion and ,gold4 ,silver ,refining ,process4 ,gold ,refining ,processes4 ,gold ,extraction ,processes4 ,calcium ,carbide and ,acetylene ,gas4 ,the ,carbide ,furnace and ,process4 ,production4 ,utilization4 ,carborundum4 ,details of ,manufacture4 ,properties and ,uses4 ,copper4 ,copper ,refining4 ,descriptions of ,refineries4 ,costs4 ,properties and ,utilization4 ,the ,elmore and similar ,processes4 ,electrolytic ,extraction ,processes4 ,electro-,metallurgical ,concentration ,processes4 ,ferro-alloys4 ,descriptions of ,works4 ,utilization4 ,glass and ,quartz ,glass4 ,graphite4 ,details of ,process4 ,utilization4 ,iron and ,steel4 ,descriptions of ,furnaces and ,processes4 ,yields and ,costs4 ,comparative ,costs4 ,lead4 ,the ,salom ,process4 ,the ,betts ,refining ,process4 ,the ,betts ,reduction ,process4 ,white ,lead ,processes4 ,miscellaneous ,products4 ,calcium4 ,carbon ,bisulphide4 ,carbon ,tetra-,chloride4 ,diamantine4 ,magnesium4 ,phosphorus4 ,silicon and its ,compounds4 ,nickel4 ,wet ,processes4 ,dry ,processes4 ,sodium4 ,descriptions of ,cells and ,processes4 ,tin4 ,alkaline ,processes for ,tin ,stripping4 ,acid ,processes for ,tin ,stripping4 ,salt ,processes for ,tin ,stripping4 ,zinc4 ,wet ,processes4 ,dry ,processes4 ,electro-,thermal ,processes4 ,electro-,galvanizing4 ,glossary4 ,name ,index4 ,the subject of this volume1 the branch of metallurgy which deals with the extraction and refining of metals by aid of electricity1 is becoming of great importance4 ,the author gives a brief and clear account of the industrial developments of electro-metallurgy1 in language that can be understood by those whose acquaintance with either chemical or electrical science may be but slight4 ,it is a thoroughly practical work descriptive of apparatus and processes1 and commends itself to all practical men engaged1 in metallurgical operations1 as well as to business men1 financiers1 and investors4 ,radio-,telegraphy4 ,by ,c4 ,c4 ,f4 ,,monckton1 ,m4,i4,e4,e4 ,with #agc ,diagrams and ,illustrations4 ,,contents3 ,preface4 ,electric ,phenomena4 ,electric ,vibrations4 ,electro-,magnetic ,waves4 ,modified ,hertz ,waves used in ,radio-,telegraphy4 ,apparatus used for ,charging the ,oscillator4 ,the ,electric ,oscillator3 ,methods of ,arrangement1 ,practical ,details4 ,the ,receiver3 ,methods of ,arrangement1 ,the ,detecting ,apparatus1 and other details4 ,measurements in ,radio-,telegraphy4 ,the ,experimental ,station at ,elmers ,end3 ,lodge-,muirhead ,system4 ,radio-,telegraph ,station at ,nauen3 ,telefunken ,system4 ,station at ,lyngby3 ,poulsen ,system4 ,the ,lodge-,muirhead ,system1 the ,marconi ,system1 ,telefunken ,system1 and ,poulsen ,system4 ,portable ,stations4 ,radio-,telephony4 ,appendices3 ,the ,morse ,alphabet4 ,electrical ,units used in this ,book4 ,international ,control of ,radio-,telegraphy4 ,index4 ,the startling discovery twelve years ago of what is popularly known as ,wireless ,telegraphy has received many no less startling additions since then4 ,the official name now given to this branch of electrical practice is ,radio-,telegraphy4 ,the subject has now reached a thoroughly practicable stage1 and this book presents it in clear1 concise form4 ,the various services for which ,radio-,telegraphy is or may be used are indicated by the author4 ,every stage of the subject is illustrated by diagrams or photographs of apparatus1 so that1 while an elementary knowledge of electricity is presupposed1 the bearings of the subject can be grasped by every reader4 ,no subject is fraught with so many possibilities of development for the future relationships of the peoples of the world4 ,india-,rubber and its ,manufacture1 with ,chapters on ,gutta-,percha and ,balata4 ,by ,h4 ,l4 ,,terry1 ,f4,i4,c41 ,assoc4,inst4,m4,m4 ,with ,illustrations4 ,,list ,,of ,,contents3 ,preface4 ,introduction3 ,historical and ,general4 ,raw ,rubber4 ,botanical ,origin4 ,tapping the ,trees4 ,coagulation4 ,principal ,raw ,rubbers of ,commerce4 ,pseudo-,rubbers4 ,congo ,rubber4 ,general ,considerations4 ,chemical and ,physical ,properties4 ,vulcanization4 ,india-rubber ,plantations4 ,india-rubber ,substitutes4 ,reclaimed ,rubber4 ,washing and ,drying of ,raw ,rubber4 ,compounding of ,rubber4 ,rubber ,solvents and their ,recovery4 ,rubber ,solution4 ,fine ,cut ,sheet and ,articles made therefrom4 ,elastic ,thread4 ,mechanical ,rubber ,goods4 ,sundry ,rubber ,articles4 ,india-rubber ,proofed ,textures4 ,tyres4 ,india-rubber ,boots and ,shoes4 ,rubber for ,insulated ,wires4 ,vulcanite ,contracts for ,india-rubber ,goods4 ,the ,testing of ,rubber ,goods4 ,gutta-,percha4 ,balata4 ,bibliography4 ,index4 ,tells all about a material which has grown immensely in commercial importance in recent years4 ,it has been expressly written for the general reader and for the technologist in other branches of industry4 ,glass ,manufacture4 ,by ,,walter ,,rosenhain1 ,superintendent of the ,department of ,metallurgy in the ,national ,physical ,laboratory1 late ,scientific ,adviser in the ,glass ,works of ,messrs4 ,chance ,bros4 and ,co4 ,with ,illustrations4 ,,contents3 ,preface4 ,definitions4 ,physical and ,chemical ,qualities4 ,mechanical1 ,thermal1 and ,electrical ,properties4 ,transparency and ,colour4 ,raw materials of manufacture4 ,crucibles and ,furnaces for ,fusion4 ,process of ,fusion4 ,processes used in ,working of ,glass4 ,bottle4 ,blown and ,pressed4 ,rolled or ,plate4 ,sheet and ,crown4 ,coloured4 ,optical ,glass3 ,nature and ,properties1 ,manufacture4 ,miscellaneous ,products4 ,appendix4 ,bibliography of ,glass ,manufacture4 ,index4 ,this volume is for users of glass1 and makes no claim to be an adequate guide or help to those engaged in glass manufacture itself4 ,for this reason the account of manufacturing processes has been kept as non-technical as possible4 ,in describing each process the object in view has been to give an insight into the rationale of each step1 so far as it is known or understood1 from the point of view of principles and methods rather than as mere rule of thumb description of manufacturing manipulations4 ,the processes described are1 with the exception of those described as obsolete1 to the author's definite knowledge1 in commercial use at the present time4 ,precious ,stones4 ,by ,w4 ,,goodchild1 ,m4,b41 ,b4,ch4 ,with #db ,illustrations4 ,with a ,chapter on ,artificial ,stones4 ,by ,,robert ,,dykes4 ,,list ,,of ,,contents3 ,introductory and ,historical4 ,genesis of ,precious ,stones4 ,physical ,properties4 ,the ,cutting and ,polishing of ,gems4 ,imitation ,gems and the ,artificial ,production of ,precious ,stones4 ,the ,diamond4 ,fluor ,spar and the ,forms of ,silica4 ,corundum1 including ,ruby and ,sapphire4 ,spinel and ,chrysoberyl4 ,the ,carbonates and the ,felspars4 ,the ,pyroxene and ,amphibole ,groups4 ,beryl1 ,cordierite1 ,lapis ,lazuli and the ,garnets4 ,olivine1 ,topaz1 ,tourmaline and other ,silicates4 ,phosphates1 ,sulphates1 and ,carbon ,compounds4 ,an admirable guide to a fascinating subject4 ,patents1 ,designs and ,trade ,marks3 ,the ,law and ,commercial ,usage4 ,by ,,kenneth ,r4 ,,swan1 ,b4,a4 7,oxon471 of the ,inner ,temple1 ,barrister-at-,law4 ,,contents3 ,table of ,cases ,cited--,part ,i4--,letters ,patent4 ,introduction4 ,general4 ,historical4 ,i41 ,,ii41 ,,iii4 ,invention1 ,novelty1 ,subject ,matter1 and ,utility the ,essentials of ,patentable ,invention4 ,,iv4 ,specification4 ,v4 ,construction of ,specification4 ,,vi4 ,who ,may ,apply for a ,patent4 ,,vii4 ,application and ,grant4 ,,viii4 ,opposition4 ,,ix4 ,patent ,rights4 ,legal ,value4 ,commercial ,value4 ,x4 ,amendment4 ,,xi4 ,infringement of ,patent4 ,,xii4 ,action for ,infringement4 ,,xiii4 ,action to ,restrain ,threats4 ,,xiv4 ,negotiation of ,patents by ,sale and ,licence4 ,,xv4 ,limitations on ,patent ,right4 ,,xvi4 ,revocation4 ,,xvii4 ,prolongation4 ,,xviii4 ,miscellaneous4 ,,xix4 ,foreign ,patents4 ,,xx4 ,foreign ,patent ,laws3 ,united ,states of ,america4 ,germany4 ,france4 ,table of ,cost1 etc41 of ,foreign ,patents4 ,,appendix ,a4--#a4 ,table of ,forms and ,fees4 #b4 ,cost of ,obtaining a ,british ,patent4 #c4 ,convention ,countries4 ,part ,,ii4--,copyright in ,design4 ,introduction4 ,i4 ,registrable ,designs4 ,,ii4 ,registration4 ,,iii4 ,marking4 ,,iv4 ,infringement4 ,,appendix ,b4--#a4 ,table of ,forms and ,fees4 #b4 ,classification of ,goods4 ,part ,,iii4--,trade ,marks4 ,introduction4 ,i4 ,meaning of ,trade ,mark4 ,,ii4 ,qualification for ,registration4 ,,iii4 ,restrictions on ,registration4 ,,iv4 ,registration4 ,v4 ,effect of ,registration4 ,,vi4 ,miscellaneous4 ,,appendix ,c4--,table of ,forms and ,fees4 ,,indices4 #a4 ,patents4 #b4 ,designs4 #c4 ,trade ,marks4 ,this is the first book on the subject since the ,new ,patents ,act4 ,its aim is not only to present the existing law accurately and as fully as possible1 but also to cast it in a form readily comprehensible to the layman unfamiliar with legal phraseology4 ,it will be of value to those engaged in trades and industries where a knowledge of the patenting of inventions and the registration of trade marks is important4 ,full information is given regarding patents in foreign countries4 ,the ,book2 ,its ,history and ,development4 ,by ,,cyril ,,davenport1 ,v4,d41 ,f4,s4,a4 ,with #g ,plates and #abf ,figures in the text4 ,,list ,,of ,,contents3 ,early ,records4 ,rolls1 ,books and ,book bindings4 ,paper4 ,printing4 ,illustrations4 ,miscellanea4 ,leathers4 ,the ,ornamentation of ,leather ,bookbindings without ,gold4 ,the ,ornamentation of ,leather ,bookbindings with ,gold1 ,bibliography4 ,index4 ,the romance of the ,book and its development from the rude inscriptions on stone to the magnificent de ,luxe tomes of to-day have never been so excellently discoursed upon as in this volume4 ,the history of the ,book is the history of the preservation of human thought4 ,this work should be in the possession of every book lover4 ,van ,nostrand's ,westminster ,series ,,list ,,of ,,new ,,and ,,forthcoming ,,volumes4 ,timber4 ,by ,j4 ,r4 ,,baterden1 ,a4,m4,i4,c4,e4 ,steam ,engines4 ,by ,j4 ,t4 ,,rossiter1 ,m4,i4,e4,e41 ,a4,m4,i4,m4,e4 ,electric ,lamps4 ,by ,,maurice ,,solomon1 ,a4,c4,g4,i41 ,a4,m4,i4,e4,e4 ,the ,railway ,locomotive4 ,by ,,vaughan ,,pendred1 ,m4,i4,mech4,e4 ,leather4 ,by ,h4 ,,garner ,,bennett4 ,pumps and ,pumping ,machinery4 ,by ,,james ,w4 ,,rossiter1 ,a4,m4,i4,m4,e4 ,workshop ,practice4 ,by ,professor ,g4 ,f4 ,,charnock1 ,a4,m4,i4,c4,e41 ,m4,i4,m4,e4 ,textiles and their ,manufacture4 ,by ,,aldred ,,barker1 ,m4,sc4 ,gold and ,precious ,metals4 ,by ,,thomas ,k4 ,,rose1 ,d4,sc41 of the ,royal ,mint4 ,photography4 ,by ,,alfred ,,watkins1 ,past ,president of the ,photographic ,convention4 ,commercial ,paints and ,painting4 ,by ,a4 ,s4 ,,jennings1 ,hon4 ,consulting ,examiner1 ,city and ,guilds of ,london ,institute4 ,ornamental ,window ,glass ,work4 ,by ,a4 ,l4 ,,duthie4 ,brewing and ,distilling4 ,by ,,james ,,grant1 ,f4,c4,s4 ,wood ,pulp and ,its ,applications4 ,by ,c4 ,f4 ,,cross1 ,e4 ,j4 ,,bevan and ,r4 ,w4 ,,sindall4 ,the ,manufacture of ,paper4 ,by ,r4 ,w4 ,,sindall4 ,d4 ,,van ,,nostrand ,,company ,publishers and ,booksellers #bc1 ,,murray ,,and #bg1 ,,warren ,,streets1 ,,new ,,york4 ---------------------------------------- ---------------------------- ,transcriber's ,notes ,the following inconsistencies were kept3 #ejj-,k4,w4 -- #ajjj ,k4,w4 back-water -- backwater bed-plate -- bedplate ,buntpapier-,fabrikation -- ,buntpapierfabrikation cc4 -- c4c4 coloration -- colouring conical-shaped -- conical shaped ,cwts4 -- cwts4 ,darthford 7cited7 -- ,dartford drum washers -- drum-washer economiser -- economizing edge runner -- edge-runner gesamte -- gesammten grams -- grammes h4p4 -- h4-p4 ,holzschliffes -- ,holzschliffs ,hydral-,cellulose -- hydra-cellulose ,india-,rubber -- ,india-rubber midfeather -- mid-feather ,mitteilungen -- ,mittheilungen oval shaped -- oval-shaped ,oxy-,cellulose -- ,oxy-cellulose oxy-cellulose -- oxycellulose ,paper-maker -- ,papermaker ,papiererzeugung -- ,papier-,erzeugung ,papierfabrikation -- ,papier-,fabrikation per cent4 -- per ,cent4 realise -- realize ,schreibwarenzeitung -- ,schreibwaren-,zeitung sugarcane -- sugar-cane utilisation -- utilization utilised -- utilized ,vulcanised -- ,vulcanization ,watermarks -- ,water-marks workman -- work-woman ,the following changes have been made3 p4 iii vers replaced by versa p4 ix ,,presse-,p,,te replaced by ,,presse-,p,,te p4 #aj ,kulturhistorischen replaced by ,kulturhistorisches 7caption ,fig4 #b7 p4 #af ,vollstandige ,muhlen replaced by ,vollstndige ,mhlen p4 #ai couch-rolls replaced by couch rolls p4 #ed back-fall replaced by backfall p4 #eg ,beaume replaced by ,baum p4 #hd tes replaced by test p4 #ada ,beaume replaced by ,baum p4 #bjc lignocellulose replaced by ligno-cellulose p4 #baj ,ubersicht replaced by bersicht p4 #bbf press-pte replaced by presse-pte p4 #bch paper makers replaced by paper-makers p4 #bef ,andes replaced by ,ands p4 #beg ,muller replaced by ,mller p4 #bei ,hoessle replaced by ,hssle p4 #bfj ,paralatore replaced by ,parlatore p4 #bfd ,muller replaced by ,mller p4 #bfg ,bookbinding replaced by ,bookmaking p4 #bfh ,parish replaced by ,paris p4 #bec - #bgb;,b ,further #ig corrections in ,german1 ,dutch and ,french book titles without separate notices4 7#d7 ,bye-,products replaced by ,by-,products 7#g7 evey replaced by every ---------------------------------------- ----------------------------