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Photomechanics, the process whereby photographic technology is used to produce printing surfaces, is the focus of the Joseph S. Mertle Collection. The collection encompasses a wide diversity of material, including books, trade journals, patents, artifacts, and the papers of prominent figures in the field. Items for this exhibit were selected with the goal of demonstrating both the variety and broad scope of material found in the collection.

Joseph S. Mertle, at the age of sixteen, was an apprentice photoengraver in Oshkosh, Wisconsin. As a means of educating himself in his craft he began collecting all available material concerning photomechanics. At the time, in 1915, there were few books on the subject. This was a practical endeavor for Mertle, as a means to increase his own skill and knowledge. Still, a passion for collection was awakened, and over the course of a long and distinguished career as a noted technician, author and trade journal columnist, Mertle continued building his library, expanding it as the literature in the field multiplied and enlarging its scope to encompass the history of photomechanics. Early in his career he realized that the detailed knowledge of all branches of the printing industry was too large an undertaking for any single individual, and therefore he specialized in photography and photomechanics.

Mertle was the author, assisted by Harry Keusch, of the book Photolithography & Offset Printing: A reference manual of modern procedure (Chicago: Graphic Arts Publishing Co., 1937). About this book, Mertle commented: "While not exactly elementary in character, every effort has been made to deal with the subject in simple language, omitting chemical and mathematical equations, which are always difficult of comprehension by the average workman." (Preface). Louis Flader and J.S. Mertle wrote a book titled Modern Photoengraving: A practical textbook on latest American procedures (Chicago: Modern Photoengraving Publishers, 1948) which received Official Recognition form the Fiftieth Annual Convention of the American Photoengravers Association, held in 1946. A unanimous resolution supported the writing of the textbook, in part because "In the absence of such a source of reliable information, our future craftsmen are compelled to acquire a working knowledge solely by observation and imitation, with but scant understanding of the basic scientific principles underlying the photoengraving processes. . . ." He also wrote, in collaboration with Gordon L. Monsen, a book titled Photomechanics and Printing (1957).

Mertle was Associate Editor of the Graphic Arts Monthly for many years; he served as Photomechanical Editor of the National Lithographer and Printing World, Historical Editor of PSA Journal and contributor to many other journals. He was a photomechanical consultant to the 3M Company from 1956 to 1958. His collection was originally with that company and was subsequently transferred to the University of Minnesota Libraries, where it is a distinguished part of Special Collections.

Photomechanics, the processes by which printing surfaces are produced by photographic methods, revolutionized the practice of printing. One important development in its history occurred in 1796, when Aloysius Senefelder of Munich invented a printing process later named lithography (from the Greek words for writing on stone). In lithography ink is repelled by water from the areas of the stone that are not to be printed and is retained on the surface that is meant to be printed. In spite of changes in methods brought about by the use of photography (the action of light on any surface) in producing metal plates used in the printing process, the basic principles of eighteenth century lithography remained constant into the twentieth century.

The Mertle Collection contains original books, journals, photographs, and manuscripts relating to photographic processes in printing from the early period to the middle of the twentieth century. The collection includes approximately 6,000 books, plus more than 1,000 artifacts and non-print items. Noteworthy items in the collection include the technical possessions and specimen reproductions made by Karel Klic, world-renowned inventor of rotogravure; the business records and correspondence of Max Levy, pioneer manufacturer of halftone screens; the private correspondence and personal effects of the American photohistorian, Edward Epstean; and the personally executed sketches of dot formations and technical data complied by halftone researcher Arthur Fruwith.

The collection also has American patents on important developments in the graphic arts and thousands of articles devoted to the processes and methods. There is also a large collection of portraits and biographical material on leaders in the fields of printing and photomechanical reproduction. Original prints of Edweard Muybridge's famous studies on animal and human locomotion are present.

Important printed works include William Talbot's The Pencil of Nature (1844) which is the first book illustrated with actual photographs; Researches on Light by Robert Hunt (1844), the first book devoted exclusively to photochemistry; the important 2nd edition (1718) of Sir Isaac Newton's Opticks; and the first photograph published in a newspaper by the halftone process, "Shantytown," from the New York Daily Graphic of March 4, 1880. A particular strength is 19th and early 20th century periodical literature, with approximately 100 titles in the collection.

Using the Collection

Click here to locate items in the online catalog from this collection (it may take a few moments to execute the search and load the results). Materials from the Mertle Collection will be identified "TC Andersen Library Rare Books (Mertle)" and the call number in the "Availability Link" column of the search results. Materials do not circulate outside of the Special Collections and Rare Books Department but photocopying is available, subject to the condition of the material and applicable copyright laws.

Exhibit Reception Speech

Robert D. Cavin, Film Quality Manager for Imation, Inc.
September 16, 1997

The Friends of the University of Minnesota Library welcome you to the Mertle Collection on the History of Photomechanics that contains a history of literature, business records, and artifacts relating to the science of imaging and photomechanics. The collection covers a period from the 1830's through the 1950's. Its contents are overwhelming and mind-numbing for the person that becomes trapped into its labyrinth of detail. The collection has a richness unparalleled in the field of graphic arts. To touch, feel and browse through the thought of those that delved into the realm of imagery will create sensations that will leave you drained at the end of a session. This is the character of the Mertle Collection.

Written words and illustrations record the events of mankind throughout the centuries. Without the ability to communicate to the masses economically, libraries would be severely limited in number and content.

The Mertle Collection has been able to capture the essence of the pioneers that pursued the science of imaging and perfection. Joseph Mertle was inquisitive. He was a photographer and engraver in the 1920's who collected and categorized the writings, material and artifacts that relate in most part to the imaging process.

Moveable Type

Throughout the centuries, scribes would laboriously write and illustrate the written word, one letter at a time, for the privileged few. Johann Gutenberg revolutionized the world by inventing moveable type for printing in 1450. Gutenberg almost single-handedly put an end to the Dark Ages with the printed page for the masses. The printed page consisted of Gutenberg's moveable type, engravings on wood blocks, steel and copper plates. Portraits and details concerning Gutenberg's creation are contained in the Mertle Collection.


Alois Senefelder invented the process of lithography in the late 1700's. Bavarian limestone was imaged, inked and used to print for the masses. Ink and water mixtures were used as the imaging medium in a lithographic press. No moveable type, only the hand of the artist and engraver was needed to image the litho stone. A new medium was created to provide a printed sheet of paper for the masses. Litho stone illustrations and commentary are contained in the Mertle Collection.


The quest to capture and share an image with others! Euclid referred to a camera obscura around 300 BC. Leonardo da Vinci described the camera obscura in some detail during the fifteenth century. The camera obscura consisted of a darkened room through which a small hole in the wall would project a reversed image, from the outside, onto an opposite wall in the darkened room. When the outdoor light vanished, so did the image vanish. The dream of "freezing a moment in time" was as elusive as "man's quest for flight." Before the 1830's it was only a dream to capture an image onto a piece of paper and share it with others.

In August of 1839 Jacques Daguerre described to the scientific press in France and England methods that could be used to capture an image, i.e. the photograph. A polished copper plate was plated with silver and sensitized with fumes of iodine. The sensitized silver surface was exposed to an image for several minutes. Mercury vapor developed the image. The imaged silver plate was fixed with thiosulfate, washed with water, dried, and mounted under glass. The photograph was viewed by reflecting the image at a particular angle, next to a dark background. Daguerreotypes record the finest detail . . . they possess a brilliance that is not achievable with a paper print. This was the dawn of photography, but duplications of the prints were limited for the masses. Literature and examples of the daguerreotypes are available in the Mertle Collection.

Photographs for the Masses

During the same period, the 1830's, Fox Talbot and Sir John Hershel announced a technique that created a paper negative, from which positive paper prints could be made. The prints were of lesser quality than the daguerreotype, but the result was photographs that were available for the masses. In 1844, Talbot published his famous work The Pencil of Nature, which used actual photographs as illustration. It appears that this is the very first publication that was illustrated with actual photographs. This priceless book resides in the Mertle Collection.


Woodcut illustrations were the mainstay of newspapers, magazines and periodicals through the 1900's. The printing process had a serious limitation . . . it could not be used to reproduce an original continuous-tone image. The press can only print a black uniform layer of ink. The halftone process breaks down the continuous-tone image into a type of modulated digital image consisting of various size dots, i.e. highlights, mid-tones and shadows. An optical illusion occurs when the resulting halftone print is viewed at a distance . . . it has the appearance of the original continuous-tone photograph. This halftone technique, combined with the printing press, provided the means of reproducing continuous-tone photographs for the masses. There were many contributors to the halftone technique during the late 1800's, i.e. Ives, von Eggloffstein, Horgan, and the Levy brothers. The Mertle Collection contains considerable detail about the Levy brothers, major contributors to the science of the halftone process . . . a media that makes the photograph economically available to the masses.


The Mertle Collection contains a wealth of information dating from the 1700's, the second edition of Sir Isaac Newton's Optics, through the 1950's. More than 6,000 books and some 1,000 original graphic arts pieces trace the history of imagery and photomechanics. Mr. Mertle sold his collection to the 3M Printing Products Division in 1958. In the mid-1980's the collection was donated to the University of Minnesota. Imation, borne of 3M Innovation, carries on the traditions of the Printing Products Division. The Mertle Collection captures the essence of the science of imagery.

The challenge is to categorize, display and make this priceless collection of rare books and artifacts available to the masses. The collection should expanded and brought up to date. The evolution of imagery is escalating at a pace that stretches the imagination. Digital imaging, computer art, holography, stochastic halftones, Hi Fi Color process printing, etc., have evolved since the 1950's. Capture the moment and the excitement of the time before it is lost forever.

My sincere thank you to the University of Minnesota and to the Friends of the Library who have made this exhibit possible. Welcome to the Joseph S. Mertle Collection and exhibit at the University of Minnesota.