Printing from stone is a branch of a new process, different in fundamental principle from all others, namely, the chemical process.

Heretofore there have been two leading printing processes for manifolding writings and drawings, one working with characters in relief, the other with sunken characters.

Of the first kind is the ordinary book-printing, in which the characters are made of metal or wood in such form that only those lines and points are elevated that are to take color, everything else being depressed. The wooden forms for cotton-printing are made thus also.

Of the second kind are all copper and zinc plates, and the cotton-print process with copper plates or cylinders. In this method the lines and points to be printed are depressed, being either engraved, etched, or stamped.

As is well known, the first method of printing is as follows: The letters, which are all at the same elevation and, therefore, furnish a plane surface, are inked with a leather ball, stuffed with horsehair. As the ball is so firm and elastic that it can touch only the elevated parts, these alone can take the color, which adheres because of its sticky nature. The same is true of the carved wood used in cotton-printing, with only the difference that, instead of rubbing with a leather ball, the wooden plate itself is laid on a cushion covered with the color, and then, being placed face down on the cloth, is hammered gently to produce the imprint.

In copper and zinc printing the method is reversed. In order to force the color into the depressed parts, which alone are to be printed, the entire plate is coated with color, and then the elevated surface is cleansed again carefully. The cleaning rag cannot reach the depressed grooves, so that more or less color adheres to these according to their various depths. Under the powerful press, which forces the paper into all the engraved parts, this color transfers itself and thus gives the desired impression.

It is evident that both methods rest on purely mechanical principles: book-printing being based on the fact that the color adheres only on those places that it can reach, and copper-plate printing depending on the fact that the color remains only in those places from which it cannot be removed by cleansing.

It is different with the chemical print. This does not depend on either elevation or depression of the design. It depends on the fact that the design is coated with a preparation of such nature that afterward the printing color, which is made from a related substance, adheres because of its chemical similarity; and furthermore, because all parts of the plate that are to remain white, have been so treated that they repel the color. These two purely chemical objects are attained fully with the new process. Daily experience proves that all fatty bodies, such as oil, butter, tallow, fish oils, etc., and all such as easily dissolve in oil, like wax, resin, etc., refuse to unite with any watery substance without the aid of some third body that will bring about such union. The chief solvent for this purpose is alkali, which, under proper manipulation, always produces a sort of soap that then is soluble in water. Sometimes, to be sure, an apparent union can be produced by violent shaking or mixing, without the use of the alkali, but at the first opportunity the fatty substances separate themselves again from the watery ones.

It is on this fact that the entire method of the new process is based. It is termed chemical printing with perfect propriety, as the reason why a fatty color, say, linseed oil varnish, will adhere only on the designed parts of the plate and is repelled by the rest of the surface, is due to the chemical properties of the materials.

It might be maintained that in the other forms of printing, color adheres from the same reason. This is true, to be sure; for it is a general law that water and oil will adhere to all bodies that are dry. But it is not the case with these fluids mutually; and in this fact lies the unique difference between the older and the new processes. A dry plate would take color over its entire surface. If, however, it is dampened, it will take oil color only on those places that are in a condition opposite to dampness. Therefore, the repelling of the color from those parts that are to remain white is the novelty.

It must not be imagined, however, that to print chemically it suffices to dampen certain parts of the plate and to coat others with fatty substance. With most of the materials available for printing, mere water does not suffice to produce a sufficiently repelling obstacle between the plate and the color.

With flinty and clayey bodies,—for example, glass, porcelain, slate, etc.,—one can manage with mere water; but then the slight adherence of the fatty color to the plate produces an opposite difficulty, by preventing any large number of impressions. Still, by using very firm and readily drying fatty substances, such as linseed oil varnish dried with litharge of silver it is possible, in case of need, to succeed fairly well.

But with such bodies as attract the color powerfully, such as all metals, wood, limestone, artificial stone-paper, etc., it is necessary so to treat all the parts of the plate that are to remain white that they attain an especial resistance to color, and thus change their natures, so to speak.

That this is possible under certain circumstances and with the proper means, with all bodies belonging to this class, I have proved by many experiments, and I shall describe the methods in this book.

Thus the new process is not to be used only on limestone, but is applicable to metal, etc.; and stone-printing or lithography is to be considered only as a branch of general chemical printing. However, as this book is to teach mainly lithography, I will occupy myself chiefly with it.

Among the bodies available for chemical printing, limestone maintains an eminent place. Not only has it an especial property of uniting with fats,—sucking them in and holding them,—but it has, also, the same propensity for taking all fluids that repel fats. Indeed, its surface unites so thoroughly with many of the latter that it forms a chemical union with them, becoming practically impenetrable for oil colors and remaining constant thereafter in repelling them so that they cannot adhere perfectly. Therefore when a plate thus prepared is dry and covered entirely with oil color, it still remains an easy matter to wash it completely, using merely water for the purpose.

This good property, combined with the low cost and the ease of obtaining the stone in Bavaria; then the advantage that it is easily polished and prepared; the further advantage that a stone of medium thickness can be ground as often as a hundred times and utilized for new work—all these properties combined made me willing to overlook a few faults, such as their weight, great volume, frequent unevenness of quality, and lastly the occasional danger of cracking. Thus I came to use these stones as the principal means for making my countless experiments, whose happy result has been to elevate stone-printing to an art by itself.

Having stated the process and the character of this form of printing, it remains only to say a few words about its value.

With every new invention there arises the question if it is useful, and if so, in how far, for science, arts, and industry. Therefore all who have no sufficient knowledge of lithography, will ask justly: What is its value? What advantages does it give that are not to be found in any other forms of printing?

To answer this, let me say the following merely in advance till later descriptions of the various processes will convince in themselves.

It is the nature of earthly being and of human imperfection that rarely is anything found that combines in itself everything to be wished for and required. So it may be said of stone-printing that it makes neither book-printing nor copper-plate printing entirely superfluous. It is possible that in the future, by perfecting the presses, lithography may equal book-printing in point of speed, as it does not now; but the convenience of the latter, enabling the printer, by merely setting cast characters side by side, to do with speed, accuracy, and symmetry what the writer can hardly do with all his skill and industry, gives book-printing its own eminent value. When, however, we come to many things produced hitherto by book-printing, such as statistical tables, letters, circulars, letters of exchange, bills of lading, visiting-cards and addresses, and other similar work, we find that these can be produced more conveniently, more readily, more cheaply, and faster and handsomer with lithography.

As to copper-printing: in the future, as lithography extends, there probably will remain an advantage with the copper in the case of only two styles, the engraving done with the engraving needle, and the etching, the latter being worked up with the graver and the cold needle. In this respect, however, the skill of the artist must be taken into account, for a good man can produce better work on stone, even in those two styles, than a less skillful man can produce on copper. We can declare the same of the stipple style in copper, when done in the style of Herr Bartolozzi, or even like the very foremost of the copper engravers in this style, Herr John of Vienna.

All other methods (and even these three if done with less care or skill on copper) must yield place to a good design on stone; especially if one takes into account the ease of execution, the lesser need for skill, the greater speed of printing, and the almost countless impressions that are possible.

For instance, printing music from the stone has a decided advantage over zinc plates, both because of smaller cost and greater beauty. It is easier to produce all kinds of script on stone, both with fatty inks and with the engraving needle. Therefore lithography serves excellently for charts and similar work, which can be done at least three times faster on stone than on copper.

If copper-printing is to reach a high degree of perfection, the printing itself must be done by very excellent workmen. Indeed, some persons allege that the very best German copper-plate printers do not yet equal the Parisians. Printing from stone is not so difficult, and only a few particular methods demand especial care or unusual knowledge. Because of the greater ease of inking, the speed of stone-printing may be assumed to be at least five times as great, often ten times, and especially so when large plates are to be printed. Besides, it is much easier to make corrections on stone than on copper and zinc. From all this it appears that lithography makes it much easier to write and design and then to print swiftly and produce any desired number of impressions, of all those works that heretofore could be produced only on copper or zinc, providing they do not demand the very greatest degree of delicacy, strength, and sharpness obtainable with copper; in a word, so long as it is not vital to attain the utmost possible artistic beauty. Further, most of these works done on stone, by only average artists and printers, usually are more beautiful than if they had been done by the same men in copper or zinc.

This property alone gives lithography a preËminent value, the more so as no great expense is incurred in establishing a plant. But in addition to this, there are several art methods peculiar to it, which cannot be imitated by book-printing or copper-print, and which make it possible for almost every writer or artist to manifold his works without any especial skill.

I will mention now only the crayon process, which enables every artist or painter to make several thousand impressions of his original drawings; also the transfer method, by means of which all that is written or drawn with fatty ink on ordinary paper can be transferred to the stone, giving countless faithful impressions. This latter process is particularly useful for government bureaus, and is being used already with great profit.

All this I believe that I can claim for lithography with fullest confidence, and I hope that everybody who becomes sufficiently conversant with it will share my belief. Thus, besides the properties of the art, we have stated its uses, and I proceed to the real instructions, through which I hope to make good artists and printers on stone.