The Invention of Lithography. Alois Senefelder

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      I tried all possible kinds of polishing and grinding without attaining my purpose completely. The result was best when I poured a mixture of one part of concentrated oil of vitriol and four or five parts of water over the stone after polishing it. This mixture, which is very sharp, has the property of boiling immediately when poured over the stone, but ceasing instantly, so that one is tempted to believe that the vitriol has sated itself and lost its power. This is not so, however; for the same fluid, placed on an untouched part of the stone, boils again at once. The reason is that a firm skin of gypsum forms at once on the stone, and this remains impervious to the fluid. If now the etching fluid is poured off and the stone is rubbed lightly with a rag, it attains a shining polish. Unfortunately this is so thin and weak that one can make barely fifty impressions without repeating the process, which involves some loss to the drawing. But if one desires to print in the present chemical style, that is, wet, and the stone is polished before the drawing, one can make several thousand imprints, which will be described in the proper place.

      All experiments to find a color easy to wipe away showed me that on a stone prepared with oil of vitriol none was better than a light oil varnish with fine Frankfurter black and some tartar. This mixture could be washed off with a weak solution in spring water of potash and common salt. However, it happened often that slight carelessness in washing destroyed designed parts which took color again afterward only after much trouble. Recollection of this occurrence, which I could not understand clearly at the time, led me some years later to the invention of the chemical stone-printing of to-day.

      I have told all these things fully in order to prove to the reader that I did not invent stone-printing through lucky accident, but that I arrived at it by a way pointed out by industrious thought. It will be seen that I knew the ink, before I thought of its use on stone. The stone I used at first only to practice writing. The ease of writing on stone lured me then to try to make it available for direct printing. To do this, I had to discover a way to rub away the black as completely from all unetched parts of the stone as the copper-plate printer can do it from his surface, in comparison with which the stone was but slightly smooth.

      At this time my further experiments with this etched form of stone-printing were entirely checked by a new, accidental discovery. Until now I had invented little that was new, but simply had applied the copper-plate etching method to stone. But this new discovery founded an entirely new form of printing, which basically became the foundation of all succeeding methods.

      Had the stone merely proved available as substitute for copper, I would have returned to copper as soon as I could afford it, despite several advantages of stone, and for the following reasons: first, the necessary weight and thickness of the stones; second, because the printing process was slower than with copper; third, because probably I never would have become sufficiently skilled in the difficult manipulation of washing off; but chiefly, because the necessary spur, the originality of the discovery, would have been lacking, since I remembered that as a child of five or six I had seen a music-printery in Frankfurt or Mainz where the notes were etched in black slate-stone. I had played often with the broken stones, which lay in a heap near our house. Enough, I was not the first discoverer of stone-etching, nor of stone-printing; and only after I made this new discovery which I will describe now, which led me from the engraved to the relief process, with my new ink, might I call myself the inventor of an art.

      At that time I could not guess that I was to invent a form of printing different even from this new and original form, a method which was to be based not on mechanical but purely chemical properties. Even this method, new in 1796, still was purely mechanical in its purpose, whereas the present printing method, which I began in 1799, may be called purely chemical.

      I had just ground a stone plate smooth in order to treat it with etching fluid and to pursue on it my practice in reverse writing, when my mother asked me to write a laundry list for her. The laundress was waiting, but we could find no paper. My own supply had been used up by pulling proofs. Even the writing-ink was dried up. Without bothering to look for writing materials, I wrote the list hastily on the clean stone, with my prepared stone ink of wax, soap, and lampblack, intending to copy it as soon as paper was supplied.

      As I was preparing afterward to wash the writing from the stone, I became curious to see what would happen with writing made thus of prepared ink, if the stone were now etched with aqua fortis. I thought that possibly the letters would be left in relief and admit of being inked and printed like book-types or wood-cuts. My experience in etching, which had showed me that the fluid acted in all directions, did not encourage me to hope that the writing would be left in much relief. But the work was coarse, and therefore not so likely to be under-cut as ordinary work, so I made the trial. I poured a mixture of one part aqua fortis and ten parts of water over the plate and let it stand two inches deep for about five minutes. Then I examined the result and found the writing about one tenth of a line or the thickness of a playing-card in relief.

      A few finer strokes had been injured slightly, but the others had hardly lost breadth noticeably and not at all in depth, so that I had good reason to hope that a well-written plate, particularly in type letter, would be susceptible of much better relief.

      Eagerly I began inking in. I used a fine leather ball, stuffed with horsehair, and inked it very gently with thick linseed oil varnish and lampblack. I patted the inscription many times with this ball. The letters all took the color well, but it also went into all spaces greater than half a line. That this was due to the over-great elasticity of the ball was clear to me. So I cleansed my plate with soap and water, made the leather tense, and used less color. Now I found color only in such spaces as were two or more lines apart.

      I saw that I could attain my purpose better with a dauber of stiffer material. I tried at once with a piece of glass from a broken mirror, and as this succeeded fairly well, I tried elastic metal plates. Finally I made an entirely satisfactory appliance out of a thin board, very smoothly planed and covered with a fine cloth.

       My further experiments with this relief plate succeeded far better than my previous ones with etched letters. The inking in was much easier, and hardly one quarter of the force was necessary for making impressions. Thus the stones were not so liable to crack, and, what was the most important for me, this method of printing was entirely new, and I might hope to obtain a franchise and even financial aid. This hope grew when I learned that Riegel of Munich, who had invented a new sort of Frankfurter black, had received ten thousand gulden to erect a factory, although no human being could use it as a sufficient substitute, as I proved by many trials. I saw the great field for my stone-printing art and did not doubt that I would obtain assistance, even should it be only a twentieth part of what Herr Riegel had received for his entirely worthless process.

      The new art was invented, and soon was sufficiently practiced; but again came the need for a little capital, to buy a press, some stones, paper, tools, and so forth. If I did not wish to give up my hopes again, I must seek some way to obtain the necessary means. All my endeavors were fruitless. Only one way showed itself. An acquaintance, who served in the artillery, had offered to pay two hundred gulden for a substitute. In my helplessness I offered myself. I thought: "Once you are in the artillery and have mastered the exercises, you can get furlough and the permission to do your printing. You can pay others to do your sentry goes, and thus there will be only a few weeks a year in which the regiment will demand your presence. As soon as you have earned a few hundred gulden you can get a substitute yourself, or, at worst—how soon six years will pass! Perhaps you can make your fortune in the artillery, too! You will display zeal, and your knowledge is such that probably few in the corps will be superior to you. Mathematics, and especially mechanics and geography, were ever your favorite studies; you were one of the first of the Munich Lyceum in these branches; therefore it is certain that you will be noticed and promoted"—and other such chimerical hopes.

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