XXIII.

Stereotyping.--Plaster Moulds.--Planing and Beveling.--Correcting

Stereotype Plates.--Process of Electrotyping.--The

“Guillotine.”--Ornamenting.

The invention of stereotyping is also a great improvement in printing.

Almost all works, after being put in type, are stereotyped; the

advantage is that a new edition can be struck off as often as called

for, without the labor of resetting the type.

The process of stereotyping differs from common printing, in that the

letters, after being set up, are cast in plates of entire pages, from

plaster of Paris moulds.

The workman in the picture is about removing the moulds from the type

beneath. The mould, forming a perfect _fac simile_ of the page intended

to be printed, is placed with others in a great oven, where it is dried

and baked hard. The edge of the oven can be seen at the right of the

picture on the following page, which represents the interior of the

Stereotype Foundery.

[Illustration: Moulding in Plaster.]

While the plaster mould is baking in the oven, the foundery man is

getting things in readiness for converting it into lead. Upon the

left, in the picture, is a high pile of bars of lead, looking like an

irregular chimney. When the bars of lead are put into the cauldron

to melt, a certain amount of antimony is put in also, to render it

brittle, and tin is added to give a brightness of surface. When the

lead, antimony, and tin are well melted, and the scum has been removed,

the composition is poured into iron moulds, where it hardens, and

comes out in the shape of the lead that was put into the kettle in the

first place. These bars of composition, lead being by far the largest

material, are put into the boiler over which you see the man working,

and melted again, making a molten mass, which is kept liquid by the

hot fire beneath and the frequent stirring. When the plaster pages, or

moulds, are well baked in the oven, they are ready to be plunged in

their lead bath. An iron pan about two feet long, a foot broad, and two

or three inches deep, is the vessel, in which is laid a false bottom of

iron, called a floater; on this are laid the plaster moulds, face down,

and the whole is covered with an iron slab, which does not, however,

rest on the plaster moulds, but upon the edge of the iron pan. An iron

handle, like that of a basket, is secured to the middle of the pan upon

the wooden stand in front of the picture. A crane overhangs the boiler,

and from it drops a hook surrounded by four legs; the hook takes hold

of the hole in the handle, and the four legs press upon the iron

cover of the pan; the crane swings round, holds the iron pan with its

plaster moulds snugly shut up in it, and suspends the body over molten

lead, lowering it until it is partly sunken in the lead but not wholly

plunged in it.

The four corners of the pan are not square; and as the iron cover does

not fit into the grooves, there is access to the interior of the pan

by this means. Down them, then, the founder pours the lead, dipping

it from the boiler, until it fills up completely all the little type

openings in the plaster moulds. Then the crane lifts it and swings it

over to the trough by which the boy is standing. It is lowered into

the water to cool, after which a crane swings it over to the wooden

standard, where one is waiting to be opened. The handle is removed, and

then the founder, taking a heavy hammer, knocks off the lead at the

corners and edges, where it has sealed up the iron lid on the pan. The

cover is removed, and the contents of the pan taken out. The plaster is

chipped off and thrown away; but now are seen lead plates of the size

of the plaster moulds, having their surface raised in letters, just as

that of the moulds was sunken in letters. The plates are about double

the thickness of the slates used in schools.

These plates are cooled, and washed free of plaster in the trough,--the

boy in the picture is now doing this,--when they are ready to go into

the finishing room, to be trimmed, planed, picked out, corrected, and

generally made ready for use in the printing-office.

In the first place, the plate is trimmed at the edges, and planed in

a planing-machine, which shaves off, from the back, strips of the

rough lead. It is beveled also; that is, the edges are shaved down

in the left hand of the three smaller machines shown in this picture:

the object of the beveling is to secure the plate afterward, when it

comes to be put on the press. It is also picked out: a workman goes

over the lettered surface with a sharp tool, clearing out letters

which have accidentally become filled up with lead, and correcting all

inaccuracies of form which he discovers.

[Illustration: Planing and Beveling.]

The man at work in this picture is planing the back of the plate

again, for the purpose of getting the requisite thickness. The knife in

this plane makes one shaving of lead, which rolls up as it leaves the

plate, like any fine shaving. To take off another shaving, a piece of

pasteboard is placed under the plate, by which it is raised a trifle

higher, and so again brought under the knife.

[Illustration: Correcting Stereotype Plates.]

A proof is taken on a common hand-press, and with this proof before him

the corrector marks such letters as were overlooked when the plate

was picked out. This proof goes into the proof-reader’s room again,

who now goes once more over the page, to see if everything is right;

and after he has marked it, back it goes to the corrector, who now,

with the printed proof-sheet before him, makes the corrections that

are required. If, for instance, a letter is set up wrong, as _pan_ for

_pen_, and has been overlooked by the proof-reader, and the plate is

cast, what is to be done?

The corrector takes a sharp tool, and punches a hole through the plate

where the interloper is, just the size of the type, and then restoring

a common type _e_, through the opening, cuts it off even at the back

of the plate, and solders it in its place with lead. In this way a

whole line of type is sometimes introduced for an incorrect line in the

plate. The corrections being made, the plate is ready for the press.

When not in use, the plates, being very valuable, are carefully put

in a box,--a large book requiring several boxes. They are stored in

fire-proof safes, made for this purpose.

While books are generally stereotyped, woodcuts are always

electrotyped. Instead of being moulded in plaster, the cut or

illustrated page goes into the electrotype room, to be moulded in wax.

[Illustration: Moulding in Wax.]

Let us look at the process.

A brass case, or very shallow, oblong pan is filled with liquid

beeswax, which stands until it has hardened. The form containing the

pages of type, well covered with fine black lead, is placed upon

the bed of the press, shown in the picture; the face of the type

is uppermost. There is an upper bed, which in the picture is swung

half-way back. This is swung all the way back, and upon it is secured

the brass case of wax. When the upper bed is brought back again, the

wax face will of course be downward, and thus will be ready to receive

an impression from the form of type resting on the lower bed; this

lower bed is movable, and is gently raised by a screw until it presses

into the wax, after the press is tightened, and now the soft wax

receives the exact impression of the type; and the upper bed being

swung back, the brass case, with its wax mould, is removed. We have got

just as far, in fact, as when the plaster in stereotyping was ready

to receive the casting. In the battery, a corner of which is seen in

the picture, are hung one, two, three, or more copper plates; and from

rods running parallel are hung the cases containing the wax moulds, one

being hung on either side of the brass plate facing it. The positive

pole is attached to the case, the negative to the copper plate; and the

connection being made, a thin film of copper appears on the surface

of the mould. This coating increases the longer the mould remains in

the battery. After ten or twelve hours it is removed, and the result

is a shell, as it is called, of the thickness of thin pasteboard, the

upper surface a perfect _fac simile_ of the original page of type or

wood-cut, every line, and every imperfection too, being reproduced. The

under surface is exactly parallel; for each projection on the upper

surface there is an indentation in the lower.

[Illustration: The “Guillotine.”]

This thin shell of copper can be bent and crumpled up; it could not

be used for printing in its present state, and it passes through a

process called “backing up.” A thin coating of tin is applied to the

back, when it is put face downward in a shallow dish, and kept in place

by a number of small elastic rods. Then it is hung over a flat cauldron

filled with melted type-metal, and lowered to rest in it. When the

plate has acquired the same degree of temperature as the metal, the

latter is ladled and poured over the plate, filling up all the hollows

and indentations, and forming a solid back of lead. The coating of tin

is first applied, as lead will not adhere to copper.

The plate, being now ready for the planing, beveling, picking, and

correcting of stereotype plates, goes through the same process that we

have before described.

When a book is to be bound, the pile of sheets which form it is made

even at the back, and a saw, working by steam, cuts shallow grooves

across the back, for the twine over which the sewing is done. Two

girls are pictured sewing at their frames,--passing the needle through

the fold of the sheet and round the upright twine, adding one sheet

at a time to the pile, until the entire book is sewed. In the large

apartment called the forwarding-room, the remaining processes of

finishing are done. The rough and uncut edges of the book are made

smooth by means of a cutting machine called the “guillotine.”

The edges of a number of books can be cut at a time, by being secured

on a movable bed, which rises so as to bring them under a stationary

knife, which cuts them smoothly as they are pressed against it.

There is also a backing-machine, for rounding the backs of books. The

book is placed in a vise, and held near the edge of the back; and the

man, working a treadle, moves a heavy roller over the back, thus

drawing up the sheets in the centre; this is that the cover may be made

fast to the book, the sides of the cover fitting tightly; the limp back

is like a hinge. The stiff pasteboard covers are made by themselves;

for instance, if a thousand copies of a book are to be made, while the

folding and sewing of the thousand books is going on in one part of the

building, in another two or three men are at work making cases; and

when each is finished, they are put together.

[Illustration: Laying on Gold Leaf.]

[Illustration: FORWARDING ROOM.]

But the stamped name on the back or ornamental work is done on the

cases, after they are covered with cloth, and before the books are

fastened into them. A brass die, or brand, is made of the title of the

book; then the covers which are to be stamped are taken by the gilders,

who first rub the white of an egg over the surface to be stamped, and

upon that lay thin gold leaf, of gossamer lightness.

[Illustration: Burnishing Gilt Edges.]

In the picture three girls are laying on the gold leaf with their

pallet knives.

The covers are now ready to be stamped by the brass die, and that is

put in place in the embossing press, seen behind the gilders. It is

kept constantly heated, and is attached to the upper part of the press

with its face down; the cases are slipped singly into the press, and

pressed up against the die, the letters of which stamp the gold into

the cloth; the rest of the gold is carefully rubbed off, and collected

and preserved.

When the edges of the leaves are to be gilded, it is done by holding

the books firmly in a vise, as seen in the cut, the gold leaf being

laid on with a pallet knife; after which the surface is polished.

The workman is seen polishing the edges with an agate burnisher. The

sheets having been pasted in their cases, and thoroughly subjected to a

powerful press, are packed and put into the trade.

[Illustration: Marbling.]

Another very curious process is marbling the edges of leaves.

In the engraving is a long trough, in which is a thin mixture of water

and gum tragacanth, over which the workman holds two dictionaries in

his hands. The colors which combine in the marbling are water-colors,

and are distributed in the seven jars with brushes. The marbler shakes

one of these brushes over the vat, the color falling is held on the

surface by the glue, and little circles of blue, or whatever was

dropped, are scattered over the water; with another brush he sprinkles

in the same way, and so on for any number of colors, producing effects

as gorgeous as the mingling colors of autumn leaves or of sunset

clouds. If a piece of paper now were dipped into the trough, it

would, when removed, be mottled or marbled. The marbling is elongated

or streaked by slowly passing a coarse rake through the water. The

marbler, taking two books, dips the edges into the trough; the gum

causes the colors to adhere to the paper, and the precise pattern

in the vat is elegantly painted on the book; the next is dipped in

a different place, and when the surface has been taken up, the scum

is skimmed off, and the colors again sprinkled on the water, and the

process repeated as long as required.

[Illustration]

[Illustration]

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