3S9 
PAPER. 
and then (ucceffively the contadfts proceed along to the 
other end, To that any rags interfperfed between thfem are 
cut in the fame manner as they would be between the 
blades of a pair of (hears. Sometimes the plates or cut¬ 
ters, k, in the block, are bent to an angle in the middle, 
inftead of being ftraight, and inclined to the cylinder fin 
this cafe, they are called elbow-plates, and of courfe the 
two ends are both inclined to the axis of the cylinder in 
oppoiite dire&ions. In either cafe, the edges of the plate 
of the block cannot be ftraight lines, but mull: be curved, 
to adapt themfelves to the curve which a line traced on 
the cylinder will of courfe have. The plates or cutters of 
the block are united, by fcrewing them all together, and 
fitting them into a cavity cut out in the wooden block H ; 
their edges are bevelled away on one fide only, as fhown at 
k in the ledlion fig. 5. The block is fixed in its place by 
being made dovetailed, and truly fitted into the bottom of 
the ciftern, fo that the water will not leak by it. The end of 
it comes through the wood-work of thecheft,and projedfs a 
fmall diftance on the outfide of it, being kept up to its 
place by a wedge; fo that, by withdrawing this wedge, the 
block becomes loofe, and can be removed, to fharpen the 
cutters, as occafion requires. This is done on a grind- 
ftone, the plates being firft feparated from each other. 
The cutters, of the cylinder are fixed into grooves, cut 
in the wood of the cylinder, at equal diftances from each 
other round its circumference, in a direction parallel to its 
axis : the number of thefe groovesis twenty ; and, for the 
wafher, each groove has two cutters or bars put into it ; 
then a fillet of wood is driven faft in between them, to 
hold them firm; and the fillets are kept faft by fpiices 
driven into the folid wood of the cylinder. The beater 
is made in the fame manner, except that each groove con¬ 
tains three bars, and two fillets, as fhown in fig. 4. 
In the operation of the cylinder, it is neceifary that it 
fliould be inclofed in a cafe, or its great velocity would 
throw all the water and rags out of the engine. This cafe 
is a wooden box L L, fig. 2. inclofed on all (ides except 
the bottom: one fide of it refts upon the edge of the vat, 
and the other upon the edge of the partition B B. The 
lines cc reprefent the edges of wooden frames, which are 
covered with hair or wire cloth ; and immediately behind 
thefe, the box is made with a bottom, and a ledge towards 
the cylinder, which makes a complete trough. The dark 
(paces, e, e, in fig. 2, (how the Situation of two openings or 
fpouts, through the fide of the cafe, which lead to flat 
lead-pipes, h, h, fig. 3, which are placed by the fide of the 
vat; the beam, F, being cut away for them. There are 
wafte-pipes, to convey away the foul water from the en¬ 
gine; for the cylinder, as it turns, throws a great quantity 
of water and rags up againft the fieves : the water goes 
through them, and runs down into the trough at e e, and 
from thence into the ends of the leaden pipes, h, h, fig. 3, 
by which it is conveyed away : d, d, fig. 2, are grooves for 
two boards, which, when put down in their places, cover 
the hair-fieves, and ftop the water from going through 
them, if it is required to retain the water in the engine. 
This is always the cafe in the beating-engines, and there¬ 
fore they are feldom provided with thefe wafte-pipes, or at 
mod on one fide only ; the other fide of the cover being 
curved, to conform to the cylinder. Except this, the only 
differeace between the wafhing-engine and the beater is 
that the teeth of the latter are finer, having 60 inftead of 
40 bars on its circumference ; and it revolves quicker than 
the wa(her, fo that it will cut and divide thofe particles 
which pafs through the teeth of the walher. 
In fmall mills, where the fupply of water is limited, 
they frequently have but one engine, and ufe it both for 
waftiing and beating, by fetting the fcrew fo as to let the 
cylinder down and make its teeth cut finer; but the fyf- 
tem of all confiderable works is to have two engines, or 
four if the fupply of water is fufficiently great. We 
have feen a very capital paper-mill containing five en¬ 
gines, w'here three of them are beaters and two waftiers; 
becapfe the beating takes fo much more time, that, when 
Vol. XVIII. No. 1249. 
the numbers are equal, the waftiers will often do too much 
for them, and they will have to (land (fill. A mill to drive 
four engines is generally made double, that is, it has two 
water-wheels, and all the machinery (hown in the plan ; 
and, if either of thefe give motion to three engines, they 
are arranged rather differently : thus the two beaters are 
placed on the fame level with each other, and this re¬ 
moves them to a greater diftance afunder than (hown in 
fig. 1. fo that the ends of the two engines, when placed 
on the fame floor or platform, will juft touch each other. 
The waftier is then placed on T:heoppofite fide of the wheel 
D, its pinion being upon the fummit of the wheel, which 
raifes it to the proper level : the vat of the waftier has a 
valve in each end, to let out its contents into either of the 
beaters at pleafure. 
The quantity of water which a paper-mill can command 
to turn its engines, generally limits the extent of its trade; 
and hence the manufacturers fnould attend to every im¬ 
provement of the machinery which can increafe their ef- 
fedt. Where the fupply of water is conftant, they work 
the engines day and night, though the making the paper, 
as it requires many workmen, is of courfe carried on in the 
day-time only. This fyftem neeefl'arily requires a large vat 
to be provided, which is called the fluff-chefl, and is a gene¬ 
ral receptacle for the pulp, where it is kept till wanted to 
be made into paper; at the fame time this mixes the pulp 
of different days’ work together, and produces an unifor¬ 
mity in the quality and colour of the paper, which is a 
great recommendation for printing large editions of 
books. 
A very large and capital paper-mill, at Maidftone in 
Kent, is worked by fteam-engines, and is found to anfwer 
very well. The machinery and building of a paper-mill 
(hould be well made, and firmly put together, otherwife 
its great velocity, and power, produces a tremor, which 
in time (hakes every thing to pieces. The noife and vi¬ 
bration of a waftiing-engine is moft tremendous; for, when 
it revolves 120 times per minute, and has 40 teeth, each 
of which pafles by 12 or 14 teeth in the block at every re¬ 
volution, it will make near 60,000 cuts per minute, and 
each of them fufficiently loud to produce the moft horri¬ 
ble growling found which can be conceived. The beater, 
revolving quicker, having 60 teeth, and 20 or 24 cutters 
in the block, will make 180,000 cuts per minute, which is 
fo rapid, as to produce a coarfe mufical note or hum¬ 
ming, which may be heard at a great diftance from the 
mill. This great number of cuts will account foran en¬ 
gine being able, in the courfe of four or five hours’ work¬ 
ing, to reduce a quantity of rags to thofe exceedingly mi¬ 
nute filaments of which paper is compofed. 
The firft and moft material point to be attended to in 
the manufacture of paper, is the preparation of the (tuff 
in the engines; and, unlefs that is properly done, it will 
be impotfible to make good paper. 
When the rags are put into the wafliing-engine, the roll 
(hould be let down fo as to gently rub on the plate ; and, 
as the rags begin to open, keep letting down the roll fo 
as to bear on the plate juft enough gradually to open the 
rags into a lint-Jlate , by which the foulnefs will pafs off as 
they keep opening into lint; and they will be perfectly 
walhed, clean, and fit for the beating-engine, in four hours 
or four hours and an half. By thus gradually opening 
the rags into a lint-ftate, a very little wafte of ftuff will 
take place from the fineft parts of the rags to what occurs 
in the common method that is ufed, of fuddenly laying 
down the roll, and tearing the rags into what is termed 
half-fluff, by which method a very great wafte of ftuff 
takes place, from the fineft parts of the rags pafling away 
with the foul water fprced through the waihing-wire; and 
it is alfo injurious to the preparation of the ftuff in the 
next procefs in the beating-engine. It is particularly to 
be attended to, that the bars in the roll, and alfo of the 
plate in the wafhing-engine, (hould not be (harp, nut in a 
cutting-ftate, but :n fuch a ftate as to gradually rub the 
rags into a lint-ftate as the walhing-procefs gcfes on. By 
5 B this 
