Up from the Stone Age

In 1796, an imaginative Munich playwright named Alois Senefelder discovered that he could print from stone. Searching for an inexpensive way to print his plays, he inscribed the smooth and porous surface with grease or crayon, dampened the stone with water, and then took his impression off on paper. The process, called lithography (literally, writing on stone), was capable of such beautiful reproductions that it was eagerly adopted by painters, among them Degas. Toulouse-Lautrec and Goya, to make cheap but faithful replicas of their original work. Except in artists' circles, Senefelder's stones have long since disappeared. But in print shops, those gloomy caverns of the publishing world where paper is imprinted with ink, the process he invented 166 years ago is enjoying a new boom.

Under another name--offset printing--the growth of lithography in the U.S. has been phenomenal. There are more companies building web* offset presses today than there were web offset presses just 25 years ago. Many national magazines with international editions reach their overseas readers via offset presses. Of the Reader's Digest's 28 foreign editions.* for example, 21 are offset-printed--and so are 72 to 96 pages, or more than 25%, of each issue of the Digest's U.S. edition (13.5 million ).

In the early 1950s only one U.S. daily newspaper, the Opelousas. La., World (circ. 10,468), ran on web offset presses.

Today. 42 dailies (and 431 weeklies) are printed by offset, among them Phoenix's Arizona Journal (circ. 54,000). born last month. Some papermakers now produce a special grade of newsprint, appropriately called "O" for offset.

Finding a Way. Printers were slow to turn to lithography, largely because they already had an excellent process. This was letterpress, a process used by the Chinese at least twelve centuries ago in which ink is transferred to paper from raised type.

Technological advances in letterpress kept pace with the pituitary growth of the U.S.

press during the 19th century. Steam-powered presses were already around; forerunners of today's giant rotary presses had appeared by the 1860s; and before the century closed. Ottmar Mergenthaler had introduced the Linotype, the first successful mechanical typesetter.

Letterpress's ability to stay abreast of the publishing demand for greater speed relegated lithography to a few humble applications, such as printing picture postcards in which the sunsets were violently pink and skies violently blue. Moreover, a new printing technique called gravure had arisen to fill a growing need for fast color printing. Gravure is the opposite of letterpress. Instead of standing out in relief, the image is etched into the plate, in a series of recesses or wells, which fill with ink and then deposit their ink loads onto paper. On fast rotary presses, gravure made possible the many-hued Sunday newspaper supplements, added a dimension to color reproduction with which letterpress could not possibly compete.

Lithography, costly and slow, might never have advanced much beyond the stone age but for the curiosity of early experimenters, among them a Nutley, N.J., lithographer named Ira Rubel. Feeding paper into his press, Rubel noticed that the inked image inadvertently printed on the cylinder when a paper sheet failed to feed through, then reprinted itself with impressive clarity on the back of the next paper sheet. This "offset"' principle, which Rubel built into a press in 1905, became the bridge by which lithography moved into the big time.

All of today's web offset presses rely on this technique. In both letterpress and gravure, the impression is taken directly from the printing plate (see diagrams}.

But in offset, an extra cylinder, composed of soft rubber, picks up the printed image from the plate and transfers it--i.e., offsets it--to the paper.

Take a Picture. With this development, the possibilities of web offset became readily visible to commercial printers. The rubber offset cylinder was able to reproduce, on rough grades of paper such as newsprint, impressions of far greater fidelity than letterpress. And since anything can be photographed, offset printing plates can be prepared without the use of metallic type. "You can make up a page," said one Midwest printer, "simply by cutting anything out of a magazine and taking a picture of it." Web offset also adapts more readily than either letterpress or gravure to many of the new experimental techniques in the printing trade, e.g., the photographic composition of type, a high-speed process in which light flashing through letter images produces photographs of words, columns and paragraphs at many times the speed of automatic typecasting machines.

But offset has its disadvantages as well.

For one. offset ink is heavier and more expensive than letterpress ink. and because it does not as readily absorb into the paper, the ink must either be artificially dried or the presses must be slowed to give the ink time to dry. For years, the fastest web offset presses ran at about one-third the speed of the fastest letter-presses. The tackier offset ink. together with the rubber cylinder, collects paper dust, which can botch a printing job. The web offset process is more wasteful of paper than letterpress. And on long offset-press runs, the ink tends to emulsify with the water played on the impression plate and thus spread until the page turns into an unrecognizable blob.

New Behemoth. But the savings that web offset offers in labor costs and makeup time have made it attractive to newspapers and periodicals of small circulation, where speed is not as essential as it is to metropolitan dailies. The time may come when offset speed will compete on near-equal terms with letterpress. In The Bronx. N.Y.. R. Hoe & Co., which makes both offset and letterpress equipment, is currently testing a web offset press, incorporating many improvements conceived by a Copenhagen printing firm, that is designed to print a 72-page newspaper, in four colors, at speeds in excess of 50,000 copies an hour. This 350-ton, $2,000,000 behemoth has been ordered by Grit, a weekly newspaper published in Williamsport, Pa., for 900,000 subscribers in small towns throughout the U.S.

Not even the most rabid disciples of web offset, the Lithographic Technical Foundation in Manhattan, envision the day when such presses will replace the letterpress giants that now spew out the nation's metropolitan dailies and the large-audience magazines. Printing presses have a long life--25 years or more--and their proprietors are not anxious to scrap an investment of billions of dollars overnight. And since offset eliminates some of the mechanical departments, any wholesale conversion to offset would be asking for serious labor trouble. Nor has letterpress technology stood still. Among recent developments: a new plastic plate, called Dycril. that adapts offset's photographic process to letterpress equipment.

But letterpress printers no longer sneer at offset. In their own shops, they have seen the offset presses rise alongside the giant letterpress machines as versatile, helpful and increasingly indispensable purveyors of the printed word.

* Web is the trade term for the continuous paper roll used on high-speed presses.

* TIME'S five international editions are printed by offset.

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