PAPER, MANUFACTURE OF 



489 



1594 



faction -will not subsequently occur ; but if decay has once commenced, it cannot I. 

 arrested by drying only. 



The operation of paper-making, after the rags or 

 materials to be used have been thus reduced and 

 prepared, may be divided into two kinds : that which 

 is carried on in hand-mills, where the formation of 

 the sheet is performed by manual labour ; and that 

 which is carried on in machine-mills, where the 

 paper is produced upon the machine wire-cloth in one 

 coutinuous web. 



With respect to hand-made papers, the sheet is 

 formed by the vatman's dipping a mould of fine wire- 

 cloth fixed upon a wooden frame, and having what 

 is termed a deckle, to determine the sizo of the sheet, 

 into a quantity of pulp which has been previously 

 mixed with water to a requisite consistency ; when, 

 after gently shaking it to and fro in a horizontal 

 position, the fibres become so connected as to form 

 one uniform fabric, while the water drains away. 

 The deckle is then removed from the mould, and 

 the sheet of paper turned off upon a felt, in a pile 

 with many others, a felt intervening between each 

 sheet, and the whole subjected to great pressure, in 

 order to displace the superfluous water ; when, after 

 being dried and pressed without the felts, the sheets 

 are dipped into a tub of fine animal size, the super- 

 fluity of which is again forced out by another press- 

 ing ; each sheet after being finally dried, undergoing 

 careful examination before it is finished. 



Thus we have, first, what is termed the water-leaf, 

 the condition in which the paper appears after being 

 pressed between the felts this is the first stage. 

 Next, a sheet from the bulk, as pressed without the 

 felts, which still remains in a state unfit for writing 

 on, not having been sized. Then a sheet after sizing, 

 which completely changes its character ; and lastly, 

 one witli the finished surface. This is produced by 

 placing the sheets separately between very smooth 

 copper-plates, and then passing them through rollers, 

 which impart a pressure of from 20 to 30 tons. 

 After only three or four such pressures, it is simply 

 called ' rolled,' but if passed through more frequently, 

 the paper acquires a higher surface, and is then called 

 ' glazed.' 



The paper-making machine is constructed to imitate 

 in a great measure, and in some respects to improve, 

 the processes used in making paper by hand ; but 

 its chief advantages are the increased rapidity with 

 which it accomplishes the manufacture, and the 

 means of producing paper of any size which cais 

 practically be required. 



By the agency of this admirable contrivance, 

 which is so adjusted as to produce the intended effect 

 with unerring precision, a process which, in the old 

 system of paper-making, occupied about three weeks 

 is now performed in as many minutes. 



The paper-making machine (fy. 159-i) is supplied 

 from the ' chests ' or reservoir, v, into which the pulp 

 descends from the beating-engine, when sufficiently 

 ground ; being kept in constant motion, as it descends, 

 by means of the agitator, G, in order that it shall not 

 settle. From this reservoir the pulp is again con- 

 veyed by a pipe into what is technically termed the 

 'lifter,' H, which consists of a cast-iron wheel, en- 

 closed in a wooden case, and having a number of 

 buckets affixed to its circumference. The trough, i, 

 placed immediately beneath the endless wire, K, is for the purpose of receiving the 



