There are few things I esteem more highly than books, and I’m not just saying that because I was honorary patron of Saskatchewan Library Week (October 15 to 22–and if you missed it, don’t worry; your local library will welcome you any week). Books have been my friends, companions and teachers since I learned to read.
Since this is a science column, not a book review, I’m not going to write about my favorite books. Instead, I’m going to focus on books as interesting objects in their own right: books as artifacts instead of art.
The most distant ancestors of the book were the clay tablets used by the people of ancient Mesopotamia. Much closer in spirit were the papyrus scrolls of the ancient Egyptians, Greeks and Romans. They were more than a bit awkward: a typical scroll was 10 metres long. Imagine having to find a reference that happens to be near the end!
In the fourth century, papyrus gave way to parchment, and the scroll gave way to the codex: many sheets gathered in small bundles, folded in the middle, stitched together through the folds and attached to wooden boards by thongs. In other words, a book.
In the Far East, the Chinese developed books made of bamboo strips strung together on cords. They also invented moveable type–but they made little use of it because of the huge number of characters in written Chinese.
In the 15th century a German printer, Johannes Gutenberg, also developed moveable type. At the same time, another innovation, paper, was spreading across Europe. (Europeans got it from the Muslims, who got it from China). The inevitable offspring of moveable type and paper are books.
A hand-operated press could print 250 pages an hour. The power-driven press, introduced in 1811, could print 1,000 pages an hour. The rotary press, introduced in 1848, could print 24,000. Today’s presses can print more than a million.
Printing methods have evolved, too. Gutenberg and three centuries of his successors used letterpress, in which raised letters deposit the ink on the paper. In 1796, a new method of printing, lithography, was developed. A design can be drawn in grease on a flat stone, the surface wetted, and then a grease-based ink applied; because grease and water won’t mix, the ink will only stick to the design, and can then be transferred to paper. Almost all of today’s books are printed by a descendant of those greasy stones called “photo offset lithography.”
Let’s walk through the production of a book.
First the book has to be written, which may or may not be a high-tech process, depending on how comfortable the author is with “processed words.” But even if the author chooses to write with a purple crayon on the back of old SaskPower bills, his or her words will promptly be put into a computer by the publisher.
The computer, via a high-resolution laser printer, produces “camera ready,” copies of the book’s pages, in whatever typeface the book’s designer has decided is most appropriate. The pages are then photographed by a large camera onto a huge sheet of photographic film, producing a full-sized negative image.
This negative image is then used to “burn” a positive image onto the printing plate. There’s more than one way to do this: in the most common method, the metal plate is coated with an ink-receptive substance that hardens and becomes insoluble when exposed to light. Where it hasn’t been exposed to light, it can be washed away. A water-receptive material that attaches only to the uncoated metal is then applied. On the press, the plate is first wet, then inked. The ink won’t stick to the wet metal, so you end up with ink only where you want it.
These metal plates don’t print directly onto the paper–that would soon wear off the image. Instead, the plate transfers its ink to a rubber-coated cylinder, which then transfers it to the paper. The image is “offset” onto the rubber cylinder from the printing plate: hence, “photo offset lithography.”
Books are printed as large sheets with many pages to the sheet. These pages are folded into “signatures,” containing either 16 or 32 pages. These signatures are then assembled in the proper sequence. In “edition binding,” the signatures are sewn together with cotton or nylon thread. In “perfect binding,” which is cheaper but not as durable, the rear folds are cut off, producing a stack of loose sheets. The back edges of these sheets are roughened, and then one or two coats of flexible glue are painted over them.
Edition-bound books are “smashed,” squeezed so that the back end of the book, with its thread, becomes the same width as the rest of the book, then they’re glued, too.
Next the signatures of both kinds of books are trimmed to their final size, which removes the top, front and bottom folds so that readers can turn the pages (always a plus). The backbone of the signatures is slightly rounded by a pair of rollers, to ensure that the front edge of the book won’t protrude past the covers; then the back edge is slightly widened and spread to create a shoulder for the cover. Finally, one or two strips of gauze, called crash, are glued to the spine. Often a strip of strong paper is also applied.
The cover (if the book is a hardcover) consists of two boards, paper to line the backbone, and the cover material itself, which may be cloth, plastic, paper or a combination. Cloth is the most durable, but it’s also the most expensive, which is why you frequently get books with cloth down the spine but extending only a little way onto the front and back covers.
The cover is glued to the book, then held in place by hydraulic presses until the adhesive dries completely.
Later, dressed up in its best dust-jacket, the book goes off to the stores, to soar to the top of the best-seller list, languish in the doldrums of mid-list, or (horrors!) slink away to end its days as a $2.95 special on the remainder rack.
But some of the best books I’ve ever read I found on the discount rack…which brings me full-circle. I’ve focused on the technology behind the production of a book, because this column is about science and technology…but how books are produced and how well they sell is ultimately of far less importance than the words they contain.
As with people, it’s what’s inside that counts.
