352 
en instrument resembling a pick-axe. The 
principal difficulty in drying (he paper con- 
#ists m gradually admitting the external air, 
and m preventing the cords from imbibing 
moisture With regard to the first of these, 
the itutch use very low sheds, and construct 
their lattices with great exactness. By this 
means the Dutch paper is dried equally, and 
is extremely supple before the sizing. They 
pi event the cords from imbibing the water by 
covering them with wax. In using such 
coids, the moisture does not continue in the 
line of contact between the paper and the 
cold, which prevents the sheet from stretch- 
ing in that particular place by its weight, and 
from the folds which the moisture in the sub- 
sequent operations might occasion. The 
Dutch also employ cords of considerable 
thickness, and place fewer of them under the 
sheets; by which means they diminish the 
points ot contact, and give a freer and more 
equal circulation to the air. 
I lie size for paper is made of the shreds 
and parings got from tanners, curriers, and 
parchment-makers. All the putrefied parts 
and the lime are carefully separated from 
them, and they are inclosed into a kind of 
basket, and let down by a rope and pulley 
into the cauldron. "This is a late invention, 
and serves two valuable purposes. It makes 
it easy to draw out the pieces of leather when 
the size is extracted from them by boiling, 
or easy to return them into the boiler if the 
operation is not complete. When the sub- 
stance is sufficiently extracted, it is allowed 
to settle for some time; and it is twice lilt red 
before it is put into the vessel into which 
they dip the paper. 
Immediately before the operation, a certain 
quantity ot alum is added to the size. The 
workman takes a handful of the sheets, 
smoothed and rendered as supple as possible, 
in his left hand, dips them into the vessel, 
and holds them separate with his right, that 
they may equally imbibe the size" After 
holding them above the vessel for a short 
space of time, he seizes on the other side 
with his right hand, and again dips them into 
the vessel. When he has finished ten or a 
dozen of these handfuls, they are submitted 
to the action ot the press. The superfluous 
s.ze is carried hack to the vessel by means of 
a sm ail pipe. The vessel in which the paper 
is sized is made of copper, and furnished with 
a grate, to give the size when necessary a due 
temperature ; and a piece of thin board or 
felt is placed between everv handful as thev 
are laid on the table of the* press. 
I he Dutch are very careful in sizing their 
paper, to have every sheet in the same handful 
ot equal dryness; because it is found that the 
dry sheets imbibe the size more slowly than 
those which retain some degree of moisture. 
1 hey begin by selecting the padges in the 
drying-house; and after having made them 
supple, and having destroyed the adherence 
between the sheets, they separate them into 
Handfuls in proportion to the dryness, each of 
them containing that number which they can 
dip at one time. Besides this precaution, 
they take care to apply two sheets of brown 
paper of an equal size to every handful. 
This brown paper, firm, solid, and already 
sized, is of use to support the sheets. 
As soon as the paper is sized, it is the prac- 
tice at some paper-mills to carry it miinedi- 
PAPER. 
ately to the drying-house, and hang it before 
it cools, sheet by sheet, on the cords. The 
paper, unless particular attention is paid to 
the lattices ot the drying-house, is apt to dry 
too fast, whereby a great part of the size goes 
olf in evaporation; or, if too slow, it falls to 
the ground. The Dutch drying-houses are 
the best to prevent these inconveniences : but 
the exchange after the sizing, which is gene- 
rally practised in Holland, is the best re- 
medy. '1 hey begin this operation on the 
handfuls of paper, either while they are still 
hot, or otherwise as they find it convenient. 
But, after the exchange, thev are careful to 
allow the heaps to be altogether cold before 
they are submitted to the press. Without 
this precaution, the size would either be 
wholly squeezed out by the press of the ex- 
change, or the surface of the paper become 
very irregular. It is of consequence that the 
paper, still warm from the sizing, grows gra- 
dually firm, under the operation of the ex- 
change, in proportion as it cools. By this 
method it receives that varnish which is 'after- 
wards brought to perfection under the press, 
and in which the excellence of the paper 
either for writing or drawing chiefly consists. 
It is in consequence of the exchanging and 
pressing that the Dutch paper is soft and 
equal ; and that the size penetrates into the 
body of it, and is extended equally over its 
surface. 
Tiie exchange after the sizing ought to 
be conducted with the greatest skill and atten- 
tion, because the grain ot the paper then re- 
ceives impressions which can never be eradi- 
cated. \\ hen the sized paper is also ex- 
changed, it is possible to hang more sheets to- 
gether on the cords of the drying-house. The 
paper dries better iu this condition, and the 
size is preserved without any sensible waste, 
because the sheets of paper mutually prevent 
the rapid operation of the external air. And 
as the size has already penetrated into the 
paper, and is fixed on the surface, the insensi- 
ble progress of a well-conducted drying- 
house renders all the good effects more per- 
fect in proportion as it is slowly dried. 
If to these considerations is added the da- 
mage done to the paper in drying it immedi- 
ately after the press of the sizing-room, whe- 
ther it is done in raising the hairs by separat- 
ing the sheets, or in cracking the surface, it is 
evident that the trouble of the second ex- 
change is infinitely overpaid by the advan- 
tage. 
When the paper is sufficiently dry, it is 
carried to- the finishing- room, where it is 
pressed, selected, examined, folded, made up 
into quires, and finally into reams. It is here 
put twice under the press; first, when it is at 
its full size, aijd secondly, after it is folded. 
The principal labour of this place consists in 
assorting the paper into different lots, accord- 
ing to its quality and faults; after which it is 
made up into quires. I he person who does 
this must possess great skill, and be capable 
of great attention, because he acts as a check 
on those who separated the paper into dif- 
ferent lots, lie takes the sheets with his 
right hand, folds them, examines them, lays 
them over his left arm till he has the number 
requisite for a quire, brings (lie sides parallel 
to one another, and places them in heaps un- 
der the table. An expert workman, if pro- 
per care has been taken in assorting the lots, 
will finish in this manner near 0080 quires in a,- 
day. 
The paper is afterwards collected into 
reams of 20 quires each, and for tire last time 
put under the press, where it is continued for 
10 or !2 hours, or as long as the demand of 
the paper-mill permits. \Ye shall explain the 
structure ol one ol the best paper-mills now 
in use. 
Plate Paper Mill, &c. figs. 1, 2, 3, explains 
the construction of an engine paper-mill. 
ABDE, fig 3, is a large vat of wood, lined 
w ith lead ; on each side of it are bolted two 
pieces of wood, F ,G : the piece Ehasa strong 
lever II jointed lo it; the other end of tins 
lever enters a mortise in the piece F, and has 
a sci ew fastened to it, which comes up through 
the top ot the piece, where a nut a is put on 
it, by turning which the lever can be raised or 
lowered at pleasure. In the middle of each 
of the levers II II, is fixed a brass socket, in 
which the spindle ot tiie cylinder I lies ; and 
on the outer end of thi spindle is fixed a pi- 
nion K, working into other cog wheels, con- 
necting wiili the water-wheel, steam-engine, 
&c. which gives it motion. The cylinder is 
made ot wood, and has a great number of 
steel cutters fixed into it, parallel to the 
axis. I bese cutters act against a similar set 
fixed into a block of wood L, fig. 2; this 
block goes through a hole in the side of the 
vat, and is kept in tight by a wedge, so that 
when the wedge is knocked out, the block 
can be taken out to sharpen the cutters : the 
ends of the cylinder work very close between 
the side of the vat, and a partition N in the 
middle ot the vat, so that none of the rags 
can get through between them : the bottom 
of the vat is raised up at M, fig. 3. to the 
same lever with the axis of the cylinder, goes 
as near to its circumference as possible with- 
out touching, and then suddenly falls down to 
tne block L. At the back of the vat a small 
leaden cistern O connects with it ; through a 
hair sieve P is a crooked pipe, which brings 
clean water to the vat ; the end of this pipe 
nas a flannel bag tied over it, to catch any im- 
purities which may be in the water. 
F ig. 1 . is a box which is put over the cy- 
linder, and rests upon the edge of the vat, 
and the partition N ; at each edge of this box 
is fixed a trough bd\ when the box is put in 
its place, these connect with the top of the 
leaden pipes ef, fig. 3. on the side of the vat: 
on the edge of these troughs hair sieves gg 
are fixed ; and before these boards, one ' of 
which is shewn at h, are slid in grooves in the 
sides of the box. The operation of the ma- 
chine is as follows: The vat is filled w ith clean 
wafer, the box fig. 2. is put over the cylinder, 
and a quantity ot rags is put into the vat. 
1 lie cylinder being turned round with a velo- 
city ot 120 revolutions per minute in the di- 
rection ot the arrow in fig. 2. draws the rags 
in between the cutters in the cylinder and 
the block L, and tears them fo pieces ; from 
the cylinder they go forwards into the vat, 
and turn slowly round in it till they come 
under the cylinder again. T he great velocity 
ol the cylinder throws the rags and water up 
against the sieves g in the box fig. ]. ; th e 
foul water runs through the sieve into the 
trough id, and from thence into the pipes 
(c/J, which convey it away, and the clean 
water is brought to thy vat by the pipe P* 
when the foul water is wanted to he kept la, 
