LITHOGRAPHY

By Charles Wilhelms.

As an embellishment to the modern book, chromo-lithographed

illustrations are quite popular and in some cases absolutely

necessary, being not only attractive, but conveying an accurate idea

of the color as well as the form of the object illustrated. Although

the illustration is nothing more than a colored print, it may be a

revelation to some when they learn of the numerous details incidental

to its production.

It may not be generally known, and yet of sufficient interest to the

reader to state that the art of lithography, or surface printing, was

invented accidentally. The inventor, Aloys Senefelder, had been

engaged for years endeavoring to find some process for etching copper

plates as a substitute for typographic printing plates; and the piece

of stone (of a kind now known as Solenhofen lithographic stone), which

eventually led him to the discovery of lithography had been used by

him as a slab upon which he had been accustomed to grind his printing

ink. The materials which he used for his acid-resisting mixture while

etching his copper plates were beeswax, soap, and lampblack, and in

selecting these materials he accidentally invented the basis for all

crayons or lithographic "tusche" or inks, now used so extensively for

drawing on stone. It seems that Senefelder finally became thoroughly

disheartened about his etched copper plates, mainly owing to the great

expense and labor connected with their production, and was about to

discontinue his efforts when the idea occurred to him to experiment

with the stone which he had used as an ink slab for so many months,

treating it in the same manner as the copper plates.

He knew that the calcareous stone was easily affected by acid and that

he could protect its surface against it by a layer of wax. After

polishing the surface of the stone and coating it with a slight layer

of wax, he made his drawing with a pointed tool, laying bare the

surface of the stone where he desired the engraving. Then applying the

acid and removing the remaining wax, he filled the etched lines with

printing ink, cleaned the surface of the stone with water, and was

enabled to obtain an impression on paper from it. This manner of

treating a stone has been employed by vignette engravers for many

years, but of late has become obsolete. The result gave encouragement

to Senefelder and induced him to renew his experiments, when he was

accidentally led a step farther in the direction of surface or

chemical printing.

Senefelder had just ground and polished a stone, when his mother

entered the room and asked him to take a memorandum of some clothes

which she was about to send away to be laundered. Having neither paper

nor ink at hand, he hastily wrote the items with a pen, dipped in his

acid-resisting mixture, upon the stone which had just been polished.

When he afterwards started to wipe the writing from the stone, it

occurred to him that it might be possible to reverse his process by

etching the surface of the stone, leaving the writing or drawing in

relief, which could be printed from in the same manner as from type.

He was fairly successful in this, and after many disappointments and

much hardship, he eventually succeeded in interesting a capitalist,

with whose assistance he was enabled to establish his new relief stone

process on a commercial basis.

The process, however, was at best only an imperfect one, and it seems

strange that the final discovery of surface or lithographic printing

should have been so long delayed, when Senefelder was in reality so

near it, when he first poured the acid over the stone containing his

laundry memorandum. If he had instantly washed off the acid and

cleaned the surface of the stone with water, he might have proceeded

to print thousands of impressions by simply keeping the surface of the

stone moist while passing the ink roller or dabber over it, then

drying and taking an impression, and repeating this operation

indefinitely. It is not surprising, therefore, that a man of such

persistence and capability as Senefelder should eventually discover

the best method for drawing and printing from stone; for it is a fact

that, since he perfected his invention, more than a hundred years ago,

it has been hardly possible to improve on his methods, so completely

did he cover the entire field of manipulation in this direction.

Continuing his experiments, Senefelder finally found that the

calcareous stone absorbed and held grease, and that it just as readily

absorbed water, where the surface was exposed and clean; that any

design drawn or transferred with a greasy crayon or ink upon a cleanly

polished stone would be firmly held, after being slightly etched; and

that after such a stone had been moistened, it could be inked with

rollers, the ink adhering only to the greasy matter constituting the

design (although it did not stand out in the relief) and that the ink

rollers would not smut the stone, the ink being repelled by the water

or moisture covering its surface. Upon this principle of chemical

affinity, the adherence of greasy substances to each other and the

mutual antipathy of grease and water, the art of lithographic printing

is based.

The methods or processes now employed in reproducing oil-paintings,

colored photographs, or water-colors by lithography are numerous, and

require great skill and experience, not only on the part of the

lithographic artist, but also on the part of the printer. Photography

has of late years been used to a great extent in creating the basis of

the color plates, to be afterwards perfected by the manipulation of

the experienced chromo-lithographer.

To insure a satisfactory result the first essential is, of course, a

good original, which can be made in water-color, oil, or pastel. The

number of printings to be employed should be predetermined and a color

scale adopted. The lithographer must carefully analyze the original

painting, making his calculations as to the best way of obtaining the

desired color effects by a judicious selection and use of his colors,

and the superimposing of one printing over the other, so as to obtain

true color values. It must be remembered that, while the average

painter has an unlimited variety of pigments at his disposal, the

lithographer is in this respect very much at a disadvantage, not

usually having more than from six to fourteen colors with which to

produce a facsimile of the original.

The first step is the making of the so-called key-plate. A piece of

gelatine is laid on the original, which is, let us say by way of

illustration, a water-color to be reproduced in ten printings, and a

careful tracing of the original is made by scratching, with an

engraving needle, the outline of each wash or touch of color composing

the picture. This being completed, the lithographic ink (tusche) or

transfer ink is carefully rubbed into the tracing, which is laid face

down on a polished lithographic stone, slightly moistened, and passed

through a hand press; thereby transferring the ink from the engraved

lines to the polished surface of the stone. The design on the stone is

then rolled in with black printing ink and etched, thus enabling the

lithographer to take the necessary ten impressions of the key-plate.

These, in their turn, are again transferred to as many lithographic

stones. This is accomplished by dusting the impressions with a red

powder, which adheres only to the design printed on the sheet. The

powdered outline design is then transferred to the surface of the

stone by passing both through a hand press. The key has been

previously provided with register marks (a short horizontal line

intersected by a vertical one) at top, bottom, and both sides. These

are of the utmost importance to the prover, and finally to the

transferrer, who prepares the work for the press, as without them it

would be impossible to register one color over the other in its proper

place. At any stage of the process, the register marks of all ten

colors, which have been made in succession on a single sheet of paper,

should coincide precisely and appear as a single mark in the form of a

small cross.

The lithographer now has before him the ten stones, each stamped with

the identical network of lines in red chalk representing his key. He

proceeds to draw each color-plate successively, at all times adhering

closely to the red chalk outlines, filling in with tusche where full

strength of the color is required and using lithographic crayon or the

stipple process to reproduce the various gradations of this color in

order to secure the full color value of each printing. The register

marks are ruled in on each stone corresponding to those on the key, so

that the prover or printer has these marks in the same identical

position on each and every color as a guide for register.

As each stone is finished it is etched; that is, treated with a weak

solution of nitric acid and gum-water, in order to remove all

accidental traces of scum from its surface, and to prepare it for

printing. Then proofs are made, which serve as a guide to the

lithographer during the progress of his work, and finally as a guide

to the transferrer and to the printer. The proving is done on a hand

press, and it is here that we have our first glimpse of chemical

printing, which, notwithstanding its simplicity, seems so mysterious

to one uninitiated in its secrets.

The writer recollects his own first experience. A stone had just been

placed fresh from the etching trough in the bed of the press, when, to

his amazement, the prover deliberately proceeded to eliminate every

trace of the drawing with a sponge saturated with turpentine. After

drying the stone by means of a fan, he passed over the surface a

sponge soaked in water, then applied black ink with a roller, when

behold, the drawing was restored in its entirety. The solution is very

simple: the greasy matter is absorbed and held by the stone and in its

turn repels water and attracts grease.

An impression is made with black printing ink on paper by passing it

through the hand press. The black impression approved of by the

lithographer, the stone is again cleaned with turpentine and proved in

the color required, and so with each color-plate, until the proof is

complete. When photography is employed, the half-tone negative takes

the place of the key. Prints are made from a reversed negative on the

sensitized surface of the stone, or on as many stones as the

color-plates require, and then manipulated by the lithographer, who

adds or modifies strength with his "tusche" or crayon, and scrapes or

washes out lights where necessary. The various modes of procedure are

too diverse to enter into here, but it may be well to mention that the

principal ones are the albumen, the asphaltum, and finally the

three-color process, the latter differing but little as far as the

artistic part of the work is concerned from that employed for making

relief printing plates for the typographic press.

The original drawing plates, or stones, are not used to print from

direct unless the edition be very small. Just as the typographic

printer uses electrotypes in place of the original type or cuts, the

lithographer makes transfers from the original stones to print his

edition and carefully preserves the original stones for future

editions. The transfers are prepared in a very simple manner. The

original stones are rolled over with a specially prepared transfer

ink, and impressions are taken from them on a paper, known under the

name of transfer paper, coated with a sizing of starch, flour, and

glycerine. By printing from the original, only one copy can be

produced at each impression, whereas by using transfers a number of

copies of the original can be printed at one impression. For example,

if the picture measures 8 x 10 inches of paper, a transfer can be made

containing fifteen copies on one sheet measuring 30 x 40 inches. In

this case fifteen impressions are made from the key-plate as well as

from each of the color-plates, on the paper, and with the ink

described above.

The first transfer to be made is that of the key-plate. The fifteen

impressions are laid in their proper positions on a sheet of paper of

the required size, and are held in position on same by indentations

made with a dull-pointed steel tool. The sheet is laid face down upon

a cleanly polished stone, which is then repeatedly pulled through a

hand press until all the ink has been transferred from the paper to

the surface of the stone. The transfer paper still adhering to the

stone is then moistened and washed off the stone, leaving the design

completely transferred to the stone. A slight solution of gum arabic

and water is then applied, the stone washed clean, and after being

repeatedly rolled in with printing ink and etched, is ready for

printing. An impression is then made in the usual manner from this

key-transfer, which impression is coated with a solution of shellac.

This is done for the purpose of rendering it impervious to the effect

of the atmosphere, thus insuring against its stretching or shrinking.

Upon this varnished key-sheet all subsequent transfer impressions of

the ten colors are "stuck up," to use the technical term, and

transferred to stone in the same manner as is employed in the making

of the key-transfer. The register marks serve as a guide in "sticking

up" the separate transfer impressions and insure an accurate register

of the colors laid over each other during the process of printing. New

register marks are placed upon the key-transfer at top, bottom, and

sides similar to those on the original (which are removed from the

transfer), and these new marks now appear on all color transfers to

serve as a guide to the steam-press printer in printing his edition.

He likewise uses the hand-press proofs of the picture as a guide in

mixing his inks.

The lithographic power printing press is constructed on the same

general principle as the ordinary typographic press, excepting that it

is provided with an apparatus for moistening the stone previous to

the application of the ink rollers. The stone containing the design is

placed in the bed of the press, and the moisture, as well as the ink,

is applied by means of rollers similar to those used in the

typographic printing press. All the ten colors are now successively

printed from the transfers on a steam press, and if it is a perfect

job, the pictures can be cut to size and delivered to the publisher.

At present the cumbrous stone and the slow-moving flat-bed press are

being supplanted by the light and pliable aluminum plates and the

fast-moving rotary presses. The aluminum plate has all the requisites

for the highest grades of lithographic or surface printing, and the

rotary press is beyond doubt a vast improvement over the flat-bed

press, not only as to speed, but also as to the quality and uniformity

of its product. The mode of procedure in making transfers to aluminum

plates is much the same as that employed in making transfers to stone.

The pliability of the aluminum plate and the ease with which it can be

adjusted to a printing cylinder has resulted in the successful

introduction and use of two-and three-color lithographic rotary

presses, printing at one operation two or three colors. It has been

demonstrated that the result is fully equal to that obtained from the

single-color press, provided good judgment be used as to the

succession of the colors or printings. This marks a new epoch in the

art of lithography and enables it to compete with the typographic

three-color process, which has been making such wonderful progress

during the last five years, and at one time seriously threatened

lithography as a medium for the reproduction of certain classes of

colored illustrations.

Our experience teaches us, however, that the surface or lithographic

and the relief or typographic method will never seriously interfere

with each other, but on the contrary by actively competing in all

matter relating to the reproductive art will continue to improve their

respective methods, and thus enable them to satisfy the continually

increasing demands on the part of the public for colored

illustrations, not only as to the quantity but particularly as to the

quality thereof.