flrongly againft that of brafs, accordingly as it
js required that the face of the cloth iliould be
niore or lefs acted upon.

\ r 4 T. Piece



328 Explanation of the Plata.

T. Piece of caft-iron, which Aides in grooves
made in the uprights U, and bears upon the
pivot V of the upper cylinder, accordingly as
the fcrews prefs upon the crofs- piece X, to
which this piece of call-iron is fixed.

Fig. 4. — The brafs cylinder feen at one end,
where it is open to receive the bars of red-hot
iron which heat it.

A. The cylinders of wood to which the brafs
cylinder communicates its motion. Inftead of
wooden cylinders, others may be fubftituted of
card-paper, compofed of the quantity of leaves
necefTary to fill the fpace which is determined
between the plates of brafs adjufted at the ex-
tremity of their axis. They are ftrongly preffed
by thefe plates, which are retained in their pofi-
tion by powerful fcrews. Cylinders of paper,
properly turned, give to fine goods a glaze which
they cannot acquire by the wooden cylinders.
They have likewife the advantage of retaining
their figure, which is not the cafe with wooden
cylinders. Thefe lafi: require to be occafionally
rectified in the lathe, and at laft become too
fmall for ufe.

The lathe ufed for turning any of thefe cylin-
ders ought to be conftru£ted in fuch a manner,
as to render it a matter of certainty that the

diameter



Explanation of tbe Plates. 329

diameter fhould continue equal from one end
to the other.

B. The cylinder of brafs.

C. The neck on which it turns in the manner
of a pivot.

D. The aperture through which the bars of
red-hot iron are introduced with tongs. The
aperture is then clofed with a cover to keep in
the heat.

U. The uprights between which the brafs
cylinder moves againft the plates V.

Fig. 5. — The form of the pieces of caft-iron
with which the cylinder is heated. Two are
commonly put in, and they are ufually changed
every hour, or oftener, according to the nature of
the work.

PLATE THE EIGHTH.

Fijf. 1 and 2 Plan and fection of a veffel

particularly defigned for fubmitting fine piece-
goods, fuch as muflins, linens, &c. to the ac-
tion of the oxygenated muriatic acid.

a. A frame armed on each fide with fmall
leaden points or pins, b, the central parts of
which are iron ; they may be altogether of iron,
painted with white lead, and well wrapped with
ftrips of linen or itring. Thefe points are of

ufe



33° . Explanation of the Plates.

ufe to fufpend the piece-goods in a zigzag form,
as is fhewn by thefe figures, either immediately
by the felvedge of the piece, or by loops of tape
fewed to the pieces themfelves.

c. Rings of lead cad upon rings of iron, which
they cover; otherwife rings of iron alone, paint-
ed with white lead, and wrapped with cloth
or twine to defend them from the mil. The
cords e> w T hich are faftened to thefe rings, pafs
over hooks at d, fixed to the cord/, which, by
means of the pulley £, is ufed to raife or lower
the frame. When the latter is entirely plunged
in the bleaching liquor, the cords are detached
from the hook g, and the veilel is covered to
prevent the introduclion of any impurities, as-
well as to defend the workmen from any dif-
agreeable odour.

An apparatus of this kind may be ufed, not
only for immerfmg of the goods in the oxvge-
nated muriatic acid, but likewife for the lees,
as well as the bath oi" fulphuric acid, 8cc.

Fig. 3 and 4. — Elevation and profile of the
frame for ftrctching the fkains of thread when
taken out of the bleaching veflels. A, upright
pieces, in which a number of holes, B, are
pierced for the purpofe of fupporting C, the
crofs-pieces, over which the fkains of thread,
D, pafs fingly. Thefe crofs-pieces have th< ir

angles



Explanation of the Pla'es. 331

angles well rounded, and are fet at a greater
or lefs diftance, according to the degree of ten-
fion to be produced, by means of the iron pins
inferted in the holes of the uprights.

The thread is firft well wrung upon the pin,
or with the hand, after which ii is fh-etched
upon the pannel, and left to dry. Care muft
be taken that thofe Ikains which are put on at
any one time fhall all be of the fame length, in
order that the tenfion may be equal throughout.

If thefe threads, when taken out of the
bleaching veflels, fhould be fo entangled or
mixed as to feem incapable of being cleared
without breaking, they may eafily be brought
to their original ftate by plunging them in water,
and gently finking them with the edge of the
hand. This operation may, if thought fit, be
repeated at each immerfion, in cafe it fhould
be fuppofed that the thread would be too dif-
ficult to clear after the entire bleaching-.

The fkains of thread, thus adjufted and dried,
are afterwards twifted together in dozens or
fcores, or any other count, according to the
cuftom of the market ; or they may be packed
in fmall parcels in coloured paper, according
to their quality, and the orders of the vender.

Fig. 5, 6, 9, 10.— Plan, profile, and parts of
the machine for fcorching or fingeing muflins,

and



332 Explanation of the Plates.

and other piece-goods, which are particularly
required to have an even face fimiJar to goods
of the fame kind imported from England.

A, ports fixed in a cavity, B, in the pave-
ment y or floor of the workfhop. They are con-
nected by the crofs-pieces, C, fixed at their up-
per extremities by the bolts or fcrews D. Thefe
pofls may be taken up at pleafure, in order to
leave more fpace in the workfhop. E, axis of
a roller placed between each poll, the pro-
longation of which is bended into a handle, F,
for regulating the tenfion of the piece by the
ratchet-wheel G. A fhort piece of cloth or can-
vas, H, is nailed to each of thefe rollers, and to
thefe the extremities or ends of the piece to be
finged are fixed with the needle or rod of iron, K.
One of thefe rollers takes up that part of the
piece which is finged, while the other gives off
or unfolds a new length to be fubje&ed to the
fame operation.

L, the bended iron, with which the fingeing
is performed by palling it over the furface, from
one edge to the other, in a light, fpeedy, and
dextrous manner. The flat part M being firft
made very hot, is well wiped on a cloth or pad,
in order that it may not foil or greafe the piece,
which laft action would endanger its being
burned. This iron is to be pafled two or three

times



Explanation of the Plates. 333

times over the extended part of the cloth, in
order that it may produce its effect more uni-
formly.

If the piece require to be finged on both
fides, it muft be afterwards turned, by chang-
ing the rollers M for N. The brown fcorched
colour which the piece acquires by this treat-
ment fpeedily disappears in the bleaching.

Fig. 7 and 8 A plate of call-iron, viewed

in face and edgewife, which is advantageoufly
ufed to fmooth or lay the nap of certain piece-
goods, fuch as velverets, fuftians, coverlets, &:c.
This plate is heated to the proper degree ; and
one or two men, according to the weight and
dimenfions of the plate, and the nature of the
fluff, pafs it along, more or lefs fpeedily, over
the piece intended to be thus ironed or fmoothed.
The fame care mult be taken to wipe the plate
when it comes out of the furnace as was de-
fcribed for the fingeing. The handles, B, of the
plate, are wrapped round with cloth, in order to
defend the hands of the workman.

Fig. 14. — -A bru(h,with ihort hair, ufed to raife
the fibres or nap of the piece-goods intended to
be fubje£ted to either of the operations here
defcribed.

Fig. 11,12 and 13. — Plan, elevation, and fec"H-
on of a prefs proper for drying or expreffing the

Water



334 Explanation of the Plates.

water from piece goods, whether in the courfe
of the f veral operations, or at the end of the
bleaching procefs. This prefs may like wife be
employed to advantage, to give a neat appear-
ance to folding goods, or for the clofe packing
of bales.

A. The platform or table of the prefs upon
which the goods are placed. This table is hol-
lowed out to the depth of one inch, and is in-
clined towards the gutter or beak, B, in order
that the waters which flow from the goods may
be received in a pail placed underneath for that
purpofe.

C. The preffing fcrews which rife and fall be-
tween the uprights, D, in order that the whole
furface of the table may be left clear.



PLATE THE NINTH.

Fig. i and i. — Plan and fecrion of the dif-
tilling apparatus mentioned at the commence-
ment of this work.

A. The double furnace with its fixed grate.
B a cover of plate-iron of a fquare or round
figure with Bat edges, which may be raifed or
placed in contact with the furnace. C the fand
bath whieh furroands the capfule ; it ought to
be verydry> fine and uniform. D, the cylindrical

bottle



Explanation of the Plates. 335

bottle with two necks ; one in the middle, E, to
receive the ftem, F, of the communication of
the pneumatic veffel, and the other for pouring
in the fulphuric acid, when muriate of foda is
ufed, or the common muriatic acid, if that fait
be not applied. Inftead of the cylindrical bottle,
a balloon, or globular veffel with a neck on one
iide, may be ufed, as is (hewn in figure 2. The
choice of thefe veffels will, in a great meafure,
depend on the fkill of the workmen, at fuch
glafs manufactories as may be in the neighbour-
hood of the bleaching works. In ftrictnefs, the
neck or tube on one fide may be difpenfed with,
and it is here mentioned only becaufe it adds a
convenience to the operation.

From thefe obfervations on balloons, it is eafily
feen, that thofe who, in purfuance of the dire£ti-
onsin the memoir upon bleaching, in the fecond
volume of the Annals of Chemiitry, may have
ufed the mattras, the neck of which fooner or
later muft break at the termination of the
chimney of the dome of the furnace there re-
commended, may afterwards ufe thefe globu-
lar veffels with advantage.

J. The door or opening to the fire-place.

Inftead of glafs bodies, it might probably be
of advantage to ufe leaden veffels heated by a
water-bath, or in any other manner which would.

not



336 Explanation of the Plates.

not endanger the fufion of thofe vefTels. This
danger would be lefs to be feared when manga-
nefe and the muriatic acid were ufed alone ;
but vefTels of this kind would always have the
difadvantage of not allowing the operator to fee
what paffed within them, as he may with glafs,
nor whether the vefTels were well cleaned. Thefe
two inconveniences, which can hardly admit of
any remedy, unlefs a glafs could be fixed in the
upper part, have hitherto prevented me from
ufing them, though they might, probably, be at-
tended with very confiderable advantages.

K. The afh-hole ; this is clofed in the fame
manner as the aperture of the furnace, by Aiding
doors ; or more limply as has been defcribed in
the explanation of the furnace exhibited in
plate I.

G. A tube of lead formed all of one piece,
without folder, and caft at one Tingle pouring,
or feveral fucceffive pourings like water pipes in
copper moulds. It may alfo be caft very fhort
at one (ingle pouring, provided it be made thick
enough to be afterwards drawn out. TheTe
fucceffive drawings reduce its thicknefs to a An-
gle line, while its internal diameter is kept at
feven or eight lines, which proportions are very
convenient. This pipe is fixed in the pneumatic
veflel in fuch a manner that it may be freely

raifed



Explanation of the Plates. 337

raifed and lowered in the groove L, made for
this purpofe in the piece which fecures it on
each fide in its place, by means of the wooden
pins M.

N. Another tube for a fecond diftilling appa-
ratus, if it be thought fit to place one befide
that already formed, whether for the purpofe of
obtaining a high degree of concentration in the
oxygenated acid, or great fpeed in the compofi-
tion of the gas, on account of the hafte required
in the work.

O. Arms of the agitator, which may be floped
off on both fides. This form agitates the liquor,
and facilitates the abforption of the gas more
effectually than any other.

P. A focket applied to the arbor 'Q of the
agitator. If the pneumatic veffel be conftrucled
according to the reprefentation in the figure,
and the explanation given in the chapter IV. the
fockets, R, here expreffed become unneceffary,
as well as the inverted ftages, whether they be
made with hoops, as at S, or conftru£ted of thin
wood-like fieves, as at T. They are placed in this
drawing only to fhew the manner of difpofing
them in cafe they fhould be preferred. The
crofs-pieces, U, of the bottoms of thefe kind of
veffels, placed upon cleats fixed to the flaves of
the veffel,, fhew the manner in which they are

z to



33 5 Explanation g/ the Plates.

to be fixed, with wooden pins, that they may
not be fubje£t to rife, nor become loofe in any
refpect.

X. The cover of the pneumatic veffel.

Y. A ftool upon which the veflel itfelf is
fupported.

Fig. 3. — Exhibits the manner in which the
hoops of thin wood are joined for the purpofe
of forming the inverted veffels, as well at their
terminations, where one part overlaps the other,
as upon the circumference attached to the bot-
tom itfelf.

a. Wooden nails with heads. Oak is the befl
material. The extremities of the hoop of thin
wood overlapping each other, and fecured on
each fide in the joint of their ligature with
wooden wedges.

b. The extremities of the circle of thin wood
lying over each other, and confined on each
fide in the joint of their ligature with wooden
wedges.

Fig. 4. — The manner in which the hoops are
put on which hold the fmall ftaves of thefecond
conftruftion together. The circles a are kept
together without binding, merely by a fcarf or
notch made in each end. Thefe hoops are
{tripped of their bark.

Cr The



Explanation of the Plates. 339

c. The flaves. Thefe, as well as the bottoms
themfelves, may be made of yellow deal.

a. The fcarfed ends of the hoops, which are
turned inwards.

Fig. 5. — The method of difpofing the tranf-
verfal bars to which the bottoms of the inverted
veflels are fixed, a the crofs-bars. b the bottom
of the inverted vefTel. c the ftaves. d the fcarfed
hoops, e wooden pins which fix the bottom of
the inverted veflfcl to the crofs bar. They are
rivetted beneath, by fplitting the lower point of
the pin, and driving a wedge into the notch. /
a fmall block or cleat, fixed to the ftaves of
the cafk with wooden pins, g, driven flan t ways
above the crofs-bar to keep it fteady in its place.

Ffsn 6. — The method of fixing the inverted
veflels, which have a border of thin wood like a
fieve. a the hoop or circle of thin wood pinned
to the circumference of the bottom, b heads of
the pins which fix the circular part, c boards
making part of the bottom, but left of a greater
length, in order that they may be fixed down to
the fupport d.

As thefe circles of thin wood are not likely to
join exactly to the circumference of the bottom
of the vefTel, they mult be made good with putty,
after previoufly flopping the larger vacuities
with tow driven firmly in. Pitch may be ufed

z 2 inftcad



34-o Explanation cf the Plates.

inftead of putty, if it fhould be found more con-
venient.

Fig. 7 and 8. — Section and plan of the veffel
for immerfing linen, hempen or cotton thread.
It is placed on rollers or trucks, a, for the con-
venience of removal.

A. Ears with the corners rounded off, which
are fupported at each end in a notch or mortice,
B, in the-crofs piece c.

d. Skains of thread, feparate or ranged in
bundles of two or three only. The pofition ot
thefe muft be changed once or twice during the
immerfion, in order that the part which refts on
the bar may be fubjected in its turn to the
action of the oxygenated muriatic acid.

E. A pipe of lead or wood, through which the
veffel is filled from beneath. If the acid were
to be poured upon the thread, it would bleach,
more fpeedily at the upper part than elfewhere.
Inftead of one pipe there may be more, or the
diameter may be fufficiently large for the fpeedy
filing of this veffel.

F. A funnel through which the bleaching
liquor flows from the pneumatic veffel. In ftricl-
nefs it may be fuppreffed, and the apparatus fa
difpofed that the cocks from that veffel may
difcharge themfelves immediately into the upper
part of the pipe, which muft be fixed withinfide

the



Explanation of the Plates. 341

the vefTel, in order that it may not impede the
covering and uncovering. The cover ought to
be corapofed of feveral portions or frames of
glafs, as was directed with regard to the vefTel
for immerfing piece-goods 3 as by this means
facility of management, and fpeed in the procefs,
are infured.

G. A fmall door or Aiding piece, in which a
plate of glafs is fet, through which it is eafy to
obfer-ve the progrefs of the work. This may be
opened from time to time to examine the goods
without railing the covers.

This method of difpofing the fkains of thread
in the oxygenated muriatic acid, is likewife ap-
plicable to their immerfion in the fulphuric acid 5
when either of thefe liquors is exhaufted, it may
eafily be drawn off, either by means of fyphons
or of a cock placed near the bottom.

Fig. 9.— Seaion of a vefTel for immerfing
piece-goods, to which a pair of hooks is ahixed to
wring out the pieces in parts at a time, particu-
larly if of considerable magnitude.

A. uprights, which may be eafily adapted to
the two oppofite fides of the vefTel by means of
the two clamps, B, which are fixed to the vefTel
with a hinge on one fide and a ftaple and pin on
the other or by ftaple and pin on each fide, if
z 3 intended



542 Explanation- of the Plate t. '

intended to be applied to other vefTels. The
lower ends of thefe uprights are inferted into
holes in the floor or pavement of the workihop.
The hook D is fixed and unmoveable. The hook
E is capable of revolving upon its fhank, the
outer end of which is fixed by plate3 of iron and
fcrews to the levers I.

The ufe of this aparatus for wringing is equal-
\y applicable to the bath of oxygenated muriatic
acid, or fulphuric acid or lees, or the macera-
tions, &c.

Fig. 10. — A tube of glafs divided into feveral
equal parts called degrees, it is of ufe to afeer-
tain the ftrength of the oxygenated acid. This
tube is eafily made out of any cylindrical bottle
or piece of tube, the lower end of which may be
(imply flopped with a cork. White glafs is to
preferred, and it is convenient that it mould be
about an inch in diameter.

Fig. 1 1 .—A fmall meaiure of glafs, tin, lead, or
pottery, which when full contains the quantity
of liquor neceffary to form one of the degrees
traced on the external furface of the tube with
a flint or the edge of a file. The trial is made
by pouring one of thefe meafures of the oxyge-
nated muriatic acid intended to be proved into
the vellel ? fig. 10, and afterwards oblervirig how

many



Explanation of the Plates* 343

many of the fame veffels filled with indigo blue,
or tincture of cochineal, &c. prepared as direct-
ed in Chapter IX — XIV, it will difcolour. .From
the refult of the experiment, the liquor is judged
to be more or lefs adapted to the bleaching
procefs ,



* 4



APPENDIX }



R,



SUPPLEMENTARY CHAPTER.



i. Nomenclature.

J\t the end of the original work, the author
has given a fhort table of fynonimous terms, to
which the following is equivalent :



Scientific Names.

Marine or muriatic acid
Oxygenated muriatic acid

Nitric acid —

Sulphuric acid — «
Ammoniac —

Carbonate of ammoniac
Aluminc —

Potato — .

Carbonate of potalh



Names in the Market, or
common isames.

Spirit of fait.

Dephlogifticated marine
acid of Scbecle.

Spirit of nitre; aqua
fortis.

O'l of vitriol.

Spirit of fal ammoniac
with lime.

Sal volatile.

Pure clay.

Pearl afti (which is im-
pure).

Salt of tartar.

Soda



346



'Appendix,



Scientific Names.

Soda —

Carbonate of Soda
Sulphate of ; otafh

of foda

â–  of alumine

. of iron

- of copper

-^— — of zinc

Acetite of copper

Muriate of foda
Oxide —



Namtt in the Market, Of
common Names,

Barilla.

Salt of foda.

Vitriolated tartar,

Glauber's fait.

Alum.

Copperas ; green vitriol.

Vitriol ; blue vitriol.

White vitriol, or cop-
peras.

Verdigris, or diftilled ver-
digris (if in cryftak).

Common fea fait.

The ruft or calx of a
metaL



2. Meafures and Weights*

I have not been able to difcover the Jaws of
graduation of the areometer of MofTy, which is
mentioned in this work. If is much to be re-
gretted that all meafures, and inftruments for
fpecific gravity, are not reduced to the. ufual
numbers, of the tables in which that of water is
taken as unity.

Meafures of Temperature, according to Reaumur's
fc ale, are reduced to that of Fahrenheit by this
Rule : Multiply the degrees by 9 - y divide thepro-
du£t by 4, and to the quotient add 32, if the

temperature



•dfpendiw 347

temperature be above the freezing water point ;
or otherwife, if below freezing, take the quo-
tient from 32. The fum or remainder will be
the degree fought.

Meafures of Length. The old French meafures
of length are ufed throughout this treatife. The
Paris foot, compared with the Englifh (Philof.
Tranf. 1768), is as 1.06575 to t, which anfwers
to fomewhat more than 12 inches and three
quarters Engliih. The Paris ell (aune) being
44 French inches, will therefore meafure 46.89
Englifh inches, or rather more than 46 inches
and feven eighths. Whence 5 Paris ells are
very nearly equal to 6§ Englifh yards, the
latter quantity being lefs than half an inch
morter.

Meafures of Capacity. The Paris pint is 2.017
Engliih wine pints, or a little more than a quart ;
and the muid of wine 280 pints, or very nearlv
707 gallons. The feptier or chopine is half a
pint. In corn meafure of Paris, 3 buihels make
1 minot j 2 minots, 1 mine j 2 mines, 1 fep-
tier ; and 12 feptiers, 1 muid. The muid is
not quite 52 Winchefter bufhcls.

Weights. The Paris pound is 7561 Englifh
grains, or one pound, one ounce, and 24I
grains avoirdupois.

Money. The livre is commonly reckoned at"

ten



34^ Appendix,

ten pence Englifh, and is divided into 20 fob,
each confifting of 12 deniers*.

With regard to the articles made ufe of, the
od of vitriol, or fulphuric acid, may be rated
at c|d per lb.; fait, at if per lb. ; manga-
nefe, about one penny per pound ; pearlafh,
6d. per lb. ; foap, 4 1. per cwt. ; coals and other
fuel very different in price, according to the
fituation of the manufactory.

3. Obfervations en the Procefs,

The new method of bleaching, for which wc"
are undoubtedly indebted to Berthollet, in his
application of the oxygenated acid, firft dif-
covered by Scheele, to this ufeful purpofe, was
very fpeedily introduced into our manufactories
at Glafgow and Manchefter, and has fince been"
very generally adopted in Ireland, Germany, and
France. Some of our bleachers in Ireland im-
merfe one thoufand pieces daily. The obftacles
which at firft impeded the progrefs of this new
aft arofe from the prejudices of bleachers, their
ignorance in chemrftry, and the real difficulties

* For the new weights, meafures, and money of France,
which, however, are not ufed in the foregoing treatife, fee
Nicholfon's Fhilof. Journal, I. 199.

of



Appendix. 349

of the procefs *, the chief of which, as is very
ftrikingly (hewn by our author, confifted in the
intolerable exhalations of the oxygenated acid,
which rendered it nearly impoffible and highly
dangerous for any workman to handle the goods
during the immerfion, while it feemed no lefs
impracticable to contrive a clofe apparatus, in
which the goods ihould be expofed through all
their parts to an equal a&ion of the bleaching
liquor. Various contrivances were tried with
little fuccefs, till it was difcovered that an ad-
dition of alkali deprived the liquor of its pun-
gent effluvia, but left it in poffeffion of its
bleaching power. It feems to have been gene-
rally thought that the only inconvenience of
this addition was the expence of the alkali ; but
Mr. Rupp f, in a lace excellent memoir, has
fhewn that the ufual addition of one pound of
pearlafli to the liquor for every three pounds
of fulphuric acid in the mattras, renders the
bleaching upon an average * $ per cent, lefs ef-
fectual, which, with the coil of the alkali adds
40 per cent, to the coft of the unfaturated liquor.