the reciuircd size is reached, anil the bar is dragged
off and laid on a floor to cool.
The operation of rolling has the effect of compress-
ing the irim, knitting its fibers together, and draw-
ing them out .so as to assume a direction longitudinal
of the bar, some extraneous matters being also re-
moved in the operation.
In the year 1783, Henry Cort, of Gosport, Eng-
land, received an English jiatent for the rolling of
iron, as a substitute for hammering. During the
following year he patented the puddling process.
Cort is the greatest name on record in the " His-
tory of Iron."
Plain rolls for reducing metal were in use before
Cort's invention, and are mentioned in Dr. John.son's
Tour, 1774 : —
'* We then saw a brass works, where the Inpif calaminnn's is
gathereJ, brolcen, wa.shed from the earth, and the lend (though
how the lead was j-epanited I did not see) then calrined. after-
ward ground fine and then mixed by fire witli copper. We paw
several strong fires with melting-pots, but the cotistruetion of
tile fireplaces I did not learn. At a copper works, which receives
its pigs of copper, 1 think, from Warrington, we saw a plnte of
copper put hot between steel rollers and spread thm. I know
not whether the upper roller was set to a certain distance, as I
suppose, or acted only by its weight. At an iron works I saw
round bars formed by a notched hammer and anvil There I
saw a bar of about half an inch or more square, cut with shears
worked by water, and then beaten hot into a thinner bar. The
hammers, all worked as they were by water, .acting upon small
bodies, moved very quick, as quick as by the hand. I then saw
wire drawn, and gave a shilling. I have enlarged my notions,
though not being able to see the movements, and having not
time to peep closely, I know less than I might.*'
Cort was the first to use grooved rolls, for which,
in combination with other improvements, a patent
was granted him. The first mention tliat we have
of the use of rolls for reducing iron is to be found
in "Coxe's Tour in Monmouthshire," where they
are said to have been invented by John Hanbury,
and used for rolling plates. This is mentioned in
a note to chapter second, by Scrivenor, "On the
Iron Trade."
Kolling-mills are of several kinds, according to the
condition or the destination of the iron.
The first set is called the forge-train, 'inuck-train,
blooming -mil I, or puddle-bar train.
The .second is called the mcrcluinl-bar train, plate-
mill, rail-mill, or vire-m ill.
The first pair of each set is the roughing down, and
the second pair is the Jinishing.
When the iron is to be re-rolled, as for nail-plates
for instance, the bars are cut into pilates of equal
length and built in piles, into a re-heating furnace,
whence they are taken and rolled in the nail-plate
train, assuming a width equal to the length of the
plates from which the nails are to be cut. See Bar-
SIIEAKS.
For special and important work, such as breaking
douti (rolling to a gage) ingots of gold or silver for
coin, a register has been contrived by Franklin
Peale, late chief coiner of the United States Mint,
Philadelphia. It has a hand and index, and the
crank on the hand arbor is the means of giving the
set to the rolls, while the hand indicates their rela-
tive distance. See Kegister.
In the Briti.sh and French departments at the
French Exposition were exhibited armor-plates for
ships originally rolled from 20 to 30 feet in length,
from 3 to 6 feet in breadth, and from 8 to 13 inches
in thickness.
An armor-plate was rolled at the "Atlas Works,"
Sheffield, England, in 1862, 20 x 4 feet, anil a thick-
ness of 1.T inches. The operation was thus described
by a spectator : —
The plate, when laid in the furnace, rests upon little stacks
of fin?-bricks. so that the flame and heat play equally round it,
till all is glowing white and the successive laiers hare settled
down into one dense ma.s8. At a signal from the furnareinan,
the bands of workmen, to the number of about 60, arranged
themselves on each side of the furnace, as near to it as they
could bear the heat. Then the doors were opened to their full-
est, and in the midst of the great light lay a ma.ss even whiter
than the rest. To this some half a dozen men drew near. They
were all attired in thin steel le.ggings, aprons of steel, and a
thin curtaiu of steel wire-work dropping over their fiices like
a large, long visor All the rest of their bodies were muffled in
thick, wet sucking. Thus protected they managed, with the
aid of a gigantic pair of forceps slung from a craue above, to
ROLLING-MILL.
1967
ROLLING-MILL.
work, as it were, atiiid the 6ame.s for a few eecond^t and to nip
the huge plate *vith the torceps. The signal was thea given,
anJ the w.iole mass of iron, fizzing, sparkling, aod shooting out
jets of lambent flame, was, by the niaiu force of chains attached
to the steim rollers, drawn forth from the furnace on to a long
wrought-iron car. The he-it and light which it then diffused
were almost unbearable in any part of the huge mill, but the
men seemed to vie with each other to approach and detach the
colo.-;sal pinchers which had drawn the iron forth. More than a
dozen attempts were made on this occaiiion before this was
effected, and more than a dozen of the best and most skillful
workmen were driven back one after another by the tremendous
heat and glare. At last all was made clear. The forceps, then
red-hot from their grip of the plate, were drawn away, the chains
cleared from the rollers, and, with a great hurrah, the other
workmen seized the chains atticheJ to the iron truck and drew
it to the incline by main force, where it was left by its own
weight to run into the jaws of the rolling-mill. It was then
sauve qui pent among the workmen, who rushed for shelter in
all directions as tiie mass was uippel between the rollers and
wound rapidly in amid quick reporus like those of dull musketry,
as the melted" iron was squeezed by the tremendous pressure out
of the mass, and flew out in jets of hquid fire on all sides. The
turning of the rollers crushes the plate through to the other
side, where it rests for a minute on a wrouglit-iron truck simi-
lar to that on which it was brought from the furnace. The ac-
tion of the rollers is then reversed after they have been, by the
action of screw levers, brought closer together by- about an inch.
Theseag.iin nip the plate and drag it biick in an opposite direction,
and again and again does the mass go furvvard an i backward, each
time pissing between a smaller space between the rollers, till the
whole of the Huge thickness is reduced to a compact mass 15
inches thick in less than a quarter of an hour. During every stage
of the process, quantities of fine sand are thrown upon the plate,
and this literaUy take-s fire as it touches the ttaniiug surface, and
covers it as it melts with a coat of silica, or with a glaze like that
of earthenware. After every discharge of sand, and these go on al-
most incessantly, buckets of water are thrown upon the plate and
explode in clouds of scalding steam ; and when these are partly
dissipated, men rush forward and with wet besoms with handles
20 feet long sweep off whatever little scraps of oxidation may
have taken place. Thus, every time the plate passes through
the mill the sand is scattered, the water th^o^vn,and the surface
swept, and at everj' roll the chief roller of the establishment
runs forward, and, under the shelter of wet cloths, measures
with a gage its thickness from end to end. The required dimen-
sions were obtained by less than a quarter of an hour's rolling,
and a plate 15 inches thick, the product of the labor of nearly
200 men and of the consumption of nearly 250 tons of coal, was
shot out by the roiliog-niills and left to cool. When this had
been effected, two large ro.lers of iron, each weighing 15 tons,
Were placed upon it by the cranes, and moved slowly backward
Fig. 4412.
Fig. 1.
u
in
ri-^— fi
_n
[— q^
1
— ^
w
Z]
Zl
and forward; and eventually, as the platecooled, were left upon
its ends to keep the whole perfectly level. Nothing farther now
remained in order to completeit as the finest specimen of armor-
plate manufacture ever attempted but to plane off its rough
ends and edges. The flat surfaces on either side, which form
what is called the skin of the plate, are never interfered with,
for the action of the steel rollers leaves them literally almo.<;t as
smooth as plate-glass.
Several devices for making the rolling of bars more continu-
ous in point of time have been suggested, and one of them uped,
the three-high train, in which the iron is passed between the
upper and middle roll, then back between the middle and lower
one, and so on. A series of six rolls in the same vertical .series
has been proposed, so that the bar might have five passages
without much loss of time.
The other proposition was to set the rolls in parallel rows, so
that the iron would pass from one set to another, preserving
the same line of motion through as many as might be necessary
to produce the grade of bar required.
The threfhigh train has three rolls in vertical order, affording
two sets of passes , one between the upper and middle roller, the
other set between the middle and the loner roller, as seen at
Figs. 4412, 4416. It is designed to enable the metal to be paf.'^ed
in each direction, rolling at each passage. Fig. 4412 shows the
three-high feature, and also the n.ode of bringing a bar grad-
ually to form by sending it through pasfesof a shape gradually
approximating that required. The triple flange is gradually
educed, as may be seen by tracing the shape from the square
bar in Fig. 1, through that series, and then through the series
in Fig 2.
Reversing-mills are generally employed in Great Britain in
preference to three-high rolls. In France,"three-high trains
hare been in use for rolling girders since the year 1849, and
everywhere upon the Continent of Europe the principle seems
to be perfectly well understood ; but the reversing-mUl is gen-
erally preferred.
Fig 4413 is an arrangement of rolls for rolling taper tubes or
rods. Each of a pair of rolls has a spiral groove of variable
depth, and of half-round section, turned on it The groove in
one roll is a right-handed, and that in the other a lift-handed
spiral, as shown in the engraving ; and when the rolls are placed
Fig, 4413.
TfiTfe-High RoUs/or making Triple- HearJed Rails.
Spiral- Grooi-f Rolls.
together and geared, so as to revolve in union, the prrooves form
a series of eyes, which, as the rol's revolve, api'K'ar to move lat-
erally and gradually decrease in size. Thus, if a bar or tapered
strip of iron, bent so as to approximately form a tube, be in-
troduced between the rolls at that end where the grooves are
largpst and deepest, it will be gradually shifted toward the
other end of the rolls as it passes between the latter, and will
thus be rolled taper.
A mill adapted to sheet-iron or sheet-load has a
plarforni like that of a \vood-]ilaning machine, except
that it ha.s rollers to enable the sheet-lead to travel
with less friction, and thus prevent buckling.
Fig. 4414 shows Bessemer'.s plan, intended to make
the plates or sheets of metal directly from fluid iron
or steel as it comes from the furnace. The metal
is allowed to flow from the ladle or funiace into
the space between two rollers, the said rolh'i"S
being provided with openings in their centers for
the circulation of water. The external surfaces of
the rollers are cooled by jets of water.
The same jdan was attempted many years ago by
Chance of Birmingham, England, for making plate-
It was abandoned.
ROLLING-MILL.
1968
ROLLING-MILL TRAIN.
Fig. 4414.
Rolling-Millfor making Plates from Molten Metai,
Owens's (Rothcrham, England) method of making tires, etc,
consists in bending a rod or roils of iron around a block, so as
to form a coil having about i the diameter and 2i or 3 times
the depth oltlie finished tire.
Thi* U brought in a furnace to a full welding heat, and trans-
ferred to a die on the anvil of a steam-haninier, whose piston
carries a .similar die. By these it i^ comp.icted into a homo-
geneous mass, wliich is expanded to the proper diimeter be-
tween two roLers, the upper one of which may be lifted to any
required distance from the lower by means of a small hydraulic
press A larijer hydraulic press is employed to force the two
rolls together in proportion as the diameter of the tire is en-
larged Other rods, adjustable by hand or automatically, serve
as guides to impart a true circular form to the blank
■DiiTerettt plms have been adopted by others for preparing
tire-blanks for th ■ rolling-machine Krupp's method consists
in forging a bar of steel into the form of a compressed hoop,
which is then cut down the middle, opened out, and afterward
finished in the rollers.
Bessemer forms an ingot of steel and cuts out the central
part, so that the annulus left may be enlarged by the rolls.
Naylor and Vickers, of Sheffield, prepare the circular steel
blanks by casting.
An cXL'inplitication of the nicety to whioh the roll-
ing of metal can be carried is shown in the process
known as nature-printing. A piece of delicate lace
is placed on a small .sheet of metallic tin, which is
then passed once between a pair of steel rolls, the
surfaces of the latter being brought in close approxi-
mation by means of actuating screws. The pattern
of the lace is reproduced with the utmost fidelity on
the tin. See Nature-printing.
Fig. 4-115 exhibits some of the many forms -which
miy be imparted to malleable iron by suitable gi'ooves
Fig. 4415
j^^ o &=o Y-f.
T
c^
a== c^
IS
TLTU
Rolled Irons.
in the rolls composing the train. Kach is made by
one continuous op.'ration. See also Figs. 2698 and
2fi99.
Pig-iron is the crude raetal from the pmelting-fumace, cast
into bxrs or pigs.
The term bar-iron is restricted to refined or wrought iron.
The bars are flat, square, round, ox-a/, half oral, or half round ;
hor^eskop is a fine qualitv of flat bar-iron : nail-rod iron, small
square iron of fine quality. Hmvij Knnds, light band*, and
hoo/> iron are thin and comparatively wide bars Raihnnd irnn
includes Hat and T rails, axle«, fish-plates, bolts, chairs, and
spikes. Huilding-iron euibraces b^am^, deck-beams, channel-
bars, T-irnn, and fittings. Angi'-iron i« known as eaun'-sided,
unequal-sided , obtuse, star, sash, etc. Sheet-iron is divided into
common, rhareoal, galvanized, and planished. Russia sheet is
s fine quality of planished charcoal iron
See IlUSsu IRO.N.
Koojing-iron is
corrugatec
or crimped
, and is either ^a/ran-
ized or black; it
is numbered accordin
a to thickness. Ta/ik
and Jire-bed iron
are similarly classified. Boiler-plate iron is
thicker than the above, that
common in
the trade varying from
^,,cto&,8inch.
IVeights of Wrought-Iron,
Sieel, Copper, and Brass Plates
soft roUfd. (Haswkll.)
Thickness determined by Am
erican Gag«.
a
O
Thickness
of each
Plates, per Square Foot.
t^
o
c
S5
Number.
Wrought-
Iron.
Steel.
Copper.
Brass.
Inch.
Lbs.
Lbs.
Lbs.
Lbs.
0000
.46
18.4575
18 7036
20 838
19 688
000
.40964
16.4368
16 6559
18.5567
17.5326
00
.3348
14.6376
14 8328
16 5254
15.6134
.32486
13.0351
13.2088
14.7162
13 904
1
.2893
11 G082
11.7629
13.10.-3
12382
2
.26763
10 3374
10.4752
11.6706
11 U266
3
.M942
9.2055
9.3283
10.3927
9 8192
4
.20431
8.1979
8 3078
9 2552
8.7445
5
.18194
7.3004
7.3977
8 2419
7.787
6
16202
6..5011
6.5878
7 3395
6 9345
7
.14428
6.7892
5.8664
6.5a59
6.1752
8
.12849
5 1557
5 2244
5.8206
6.4994
9
.11443
4.5915
4.6527
6.1837
4,8976
10
.10189
4.0884
4.1428
4.6156
43609
11
.090742
3 641
8 6896
4.1106
3.8838
12
.080808
3.2424
3.2856
3.6606
34586
13
.071961
2.8874
2.9259
3 2598
3.0799
14
.064084
2.6714
2 6057
2.903
2.7428
15
.067068
2 2899
2.3204
2.5852
2.4425
16
.05082
2.C392
2.0664
2 3021
2.1751
17
046257
1.R159
18402
2.0501
1937
18
.040303
1.6172
1.6387
1.8257
1725
19
,035R9
1.44
1.4593
16258
1.6361
20
.031961
1.2824
1.2995
14478
1. 31579
21
.028462
1.142
1.1.573
12893
12182
22
.02.';347
1017
1.0306
1.1482
1.0.-49
23
.022571
.9067
.9177
1.0225
.96604
24
.0201
.8065
.8173
.91053
.86028
25
.0179
.7182
.7278
.81087
.76612
26
.01594
.6896
.6481
.72208
.68223
27
.014195
.5696
. 772
.643118
.60755
28
.012641
.6072
.514
.57264
.54103
29
.011257
.4517
.4577
.50994
.4818
30
.010025
.4023
.4076
.45413
.42907
31
.008923
.3582
.363
.40444
.88212
32
.00795
.319
.8232
.36014
.840:6
33
.00708
.2841
.2879
.32072
.30302
34
.006804
2529
.2563
.28557
.26981
35
.005614
£253
.2283
.26431
.24028
36
.005
.2006
.2083
.2265
.214
37
.004453
.1787
.181
.20172
.19059
3S
.003965
.1591
.1612
.17961
.1697
39
.003531
.1417
.1436
.15995
.15113
40
.003144
.1261
.1278
.14242
.18456
Specific gravities
7.704
7.806
8,698
8.218
Weights of a cu-
bic foot (lbs.).
48125
487.75
543.6
513 6
Weights of a cu-
bic inch (lbs.).
.2787
.2823
.3146
.2972
1
Roll'ing-mill Train. The sy.<item of grooved
rollers liy wIul'Ii iron biMS are graiUuiUy drawn down
from balls or blooms.
The rolls in Fig. 4416 are arranged in series of
three each, each liaving grooves eorres|ionding to
those in the roller above or below it. The rough bar
is drawn through the largest fir.st and then through
the ne.xt smaller, and so on in succession to the
smallest, by which the fini.shed bar is completed.
The grooves are of sueh sections as to form S(|nare,
round, T, or other angle iron, and are known as
pisfics.
Fig. 4417, n a' and b V are two-high grooved rolls
made of chilled cast-ii-on. The former are designed
for rolling Hat and the latter S(|uare bars. Nuts c c'
regulate the distance of the rolls from eacli other,
and the tubes d d' serve to convey water for cooling
ROLLING-PENDITLUM.
1969
ROMAN BALANCE.
Fig. -HIU
Three-Hlsh RoUing-Mia Train for Merc/iartt Bar.
the inacliinery. By means of the coupling e, the
rolls are put in or out of gear with the motor which,
throu!<h the mcilinm of the gears//", can.ses the up-
per and lower rolls to rotate in opposite directions.
Fig. 4417.
Rol!ing-M,!l Train.
Roirjng-pen'du-lum. A cylinder caused to
oscillate in small cxcuisions on a horizontal plane.
It was designed a-s a time-measurer, but appeal's to
have answered no practical purpose.
Roll'ing-pln. (Domestic.) A wooden cylinder
having a projecting handle at each end, by which
dougli is rolled into .sheets suitable for pie-crust, etc.
Roll'ing-press. 1. (Printing.) The copperplate
printiiig-jiress in which the plate and bed pass be-
neath a roller by means of rotation applied to the
latter. A certain degree of elasticity is afforded bj-
a sheet or two of paper between the plate and the
bed and a number of blankets on the roller. See
C0PPERPL.\TE Pp.lNTING-PltES.S.
2. (Bnokhiadiii^.) A machine for smoothing and
condensing tile leaves of books as a substitute for
hannnering. It usually consists of a pair of iron
rollers turned by a crank, and having a table at each
side for the feeding and delivery of the packets be-
tween plates.
Fig. 4«S.
Roll'ing-press'ure Press. A baling-press In
whiuh the lol lower is depressed by the pressirre
of the roller i at the end of the e.xtension-bar g,
which traverses to and fro, as rocked by the levers
f /. The downward posi-
tion of the follower is sus-
tained liy serewsy/
Roll'ing-stock. (Eail-
u-atj.) The cars of all de-
sciiptions which traverse the
rails of a railway. See Loco-
MOTivE; Railway-car.
See also list and general in-
dex under R.^ilway Exgi-
KEEHi.vo and Pl.\nt.
The return of railway
rolling-stock, as given in
"Poor's Manual" for 1874,
1875, on the roads of the United States and Canada,
is as follows : —
Pas.«€ng«r-cars of all cla^ees 2,900
Bnggagc. mail, and e-xpress cars 4,157
Box . uiercluiudi.'^e, and bou.<^! cars 87 ,0(l9
Platform, gondola, and flat cars 52,198
Ptock-cars 14.222
Coal^;ars (number of wheel.^ not stated) 66,887
Four-wbeel cars (mostly coal) 37,892
Caboo>e-cars 1,549
Oil-cars 3,154
Ore cars 2,1(12
Lumber-cars 193
Freight-cars not classified ^4,694
RoUin^-PressNrf Baling
124
Tot.il 373,959
Locomotive engines 14,939
Deducting from the.-ie aggregates 774 engines and 13,980 cars
of allclai^ecs, .as returned by the Canada roads, leaves for the
roads in the L'nited States a total of 14,l(Jo engines and 359,979
cars, exclusive of what are denominated service-cars, and ex-
clusive of narrow-gage cars.
RoU'ing-tack'le. (Xatilicnl.) A tackle which
keeps a yard over to leeward when the ship rolls to
windwaid. It is hooked to the weather iiuarter of
the yard, and to a lashing on the mast near the
slings.
Roll-joint. A sheet-metal joint in which the
parts are lolled iipon one another and pressed tight.
RoU-lathe. ' (Mttckiiten/.) A lathe for turning
off rolls for lolling-raills, calendering-machines, and
for other purposes. In Fig. 441!), it is shown as
having a pair of rests a a, in which the journals of
the heavy iron roll rest, .so sis to take the weight
from off the centers. The inan<lrel of the head-stock
is driven by the usual slow -speed geaiing from the
band-pulley b. c is the slide-rest which carries the
tool.
RoU-mold'ing. (Architcciure.) A molding
used ill (iotliic architecture, the upper half of
which extends over tlie lower half, as if it were
formed of a thick substance rolled up.
Rom'al. (Fnln-ic.) An Indian silk.
Ro'mau Bal'ance. An instrument for weigh-
ing, consisting of a lever h.aving arms of unequal
weight on the respective sides of its point of suspen-
KOMAN-CANDLE.
1970
ROOF.
Fig 4419.
Roll- Lathe.
sion, and a /jo^Mvliic-h traverses the longer, graduated
linili. SiH' .SrKKi.YAUi).
Ro'iuan-can'dle. {Purotcchny.) a. A tube (an
old gun-banvl sawn oli" -short is l)est) is partially filled
with alternating perforated stars and small charges
of gunpowder. Fire communicated to the upper end
ignites the charges successively, which throw out the
stars until all are discharged.
h. A similar firework in paper tube.
Ro'mau-cem'ent. A kind of cement originated
about ISl'i, by Parker, of London. The term
''Koman" is a misnomer. Septaria — nodules of
indurated clay with lime and iron — are burned,
ground, and mixed into a mortar with lime and
sand. It hardens very (juickly, and is veiy durable.
See Pozzi'OLANA ; Hydraulic Cement ; Cement.
Ron'dle. {Metal-working.) A round plate or
disk. The term is applied to the crust or scale
which fin'ms upon the surface of molten metal in
cooling, and which is removed from the crucible or
cistern from time to time as it congeals, in order to
obtain the metal in a form suitable for farther treat-
ment instead of in a solid mass. Spelleil also rondcVc.
Copper thus treated is known as rose copper^ from its
red color, and the disks are known as roscUca ; they
are again refined to restore or acquire malleability
by the reduction of the suboxide of copper.
Ron-geant' Style. A mode of calico-printing.
See DisciiAi; ;e-si'yle.
Rood-loft. {Archilrctiirc.) A gallery over the
entrance to tlie choir in medieval churches, at the
front (if wdiich a large rood or crucilix was usually
placed.
Roof. 1. {Architecture.) The uppermost mem-
ber (»f a building. It consists of th^ framework and
the covcrhirf.
The folhjwing table shows the structure, flattest
ordinary slope, and weight in pounds per square foot
of several kinds of roofs : —
Flattest ordinary Weight in lbs.
Material Slope. per s(i. foot.
Sheet-copper, .022 inch thick.. 4° 100