Wooden world wide web

2. September 2010 09:27

Ramelli's bookwheel, taken from his 1588 book Le diverse et artificiose machine

I've just reviewed Boffinology: The real stories behind our greatest scientific discoveries by Justin Pollard. It's a collection of short, snappy tales from the history of science, from the invention of Velcro to Einstein turning down the position of President of Israel.

It's an enjoyable read that emphasises the human side of science and technology through the ages (my review is here). Most of the stories have been told before, however. From the ancient world, for example, Archimedes, Hero of Alexandria and Thales of Miletus are all rather predictably featured.

But jumping ahead a millennium and a half, I was happy to see a short description of one of my favourite historical inventions, Agostino Ramelli's 16th-century revolving bookcase.

I came across this intriguing contraption when I was researching Decoding the Heavens, because like the Antikythera mechanism, the bookcase makes use of epicyclic gearing. This type of gearing is quite hard to get your head around without a diagram but basically it involves gear trains riding around on other wheels, so you get one set of circles imposed on another.

The Antikythera mechanism, which dates from the 1st or 2nd century BC, is by far the oldest known example of epicyclic gearing. Its creator used the technique to model the varying motion of the Moon, and perhaps also the Sun and the planets. The same principle was used in astronomical clocks in Europe from the 14th century onwards.

Ramelli used the gearing for a quite different purpose, however. His invention carries books.

An Italian military engineer, Ramelli worked for rich and powerful patrons in France, including King Henry III. His major surviving work, called "The Various and Ingenious Machines of Agostino Ramelli", was published in 1588. His machines include water pumps, bolt cutters, siege engines and portable bridges. But there are also several household gadgets, including the revolving bookcase.

Such bookcases did already exist but they rotated about a vertical axis, like a merry-go-round or "lazy susan". Ramelli's rotated about a horizontal axis, like a water wheel. Of course such a device would normally tip all of the books onto the floor as it turned, which is where the epicyclic gearing came in. Epicyclic gear trains caused each shelf to make one counter-rotation for each full turn of the bookcase, keeping them at the same angle - about 45 degrees - with respect to the floor, and ensuring that the books stayed safely in position. (The top image, taken from Ramelli's 1588 publication, shows a cross-section of this gearing.)

Ramelli wrote about his device: "This is a beautiful and ingenious machine, very useful and convenient for anyone who takes pleasure in study, especially those who are indisposed and tormented by gout. For with this machine a man can see and turn through a large number of books without moving from one spot."

Ramelli's invention took up a lot less floor space than a conventional revolving bookcase. But the complex gearing involved was hardly practical. As later scholars pointed out, it would have been much easier to hang the shelves independently of the main wheel, so gravity would keep them at the proper angle.

Ramelli's bookwheel, as pictured in a later 18th century publicationHistorian Bert Hall, now at the University of Toronto in Canada, published an analysis of the bookcase back in 1970 (Technology and Culture, vol 11, pp 389-400). He says that Ramelli often used complex gearing to perform tasks that could have been achieved more easily using other means. The inventor didn't really expect such devices to be used, says Hall. He was simply showing off his virtuosity, "just as we today would expect an artist to demonstrate a particular personal ‘style' in his paintings". Hall suggests that Ramelli may even have conceived the whole bookcase simply to demonstrate his knowledge of epicyclic gearing.

But besides showing off the potential of this gearing technique, Ramelli's device also has a peculiarly modern significance that Hall, writing in 1970, could not have realised.

The bookwheel allowed a scholar to work on several open texts simultaneously, flipping quickly from one to another without losing his or her place (see second image, taken from an 18th century publication). So Ramelli's invention foreshadowed the concept of cycling through various texts or windows of information. Of course this principle pretty much defines the way we now access and work with information, from the ability to flip between different tabs on our computer screens to the hypertext links between pages on the world wide web.

In Boffinology, Pollard even describes the bookcase as a "wooden world wide web". He says: "The ability to read many texts at once and jump between them was a novelty and Ramelli's machine might be claimed an even more distant predecessor of hypertext than Vannevar Bush's Memex machine."

Actually, scholars were reading several texts at once for a long time before Ramelli. But he may well have been the first to develop a piece of technology specifically to enable such parallel study.

What Pollard doesn't mention is that (like the Memex machine) Ramelli's device was never built. Indeed as the Dead Media Archive puts it, the bookwheel is a fascinating example of a medium that was dead even when it was alive: "It was influential without ever actually existing."


Comments (1) -

12/23/2010 1:44:00 AM #

Great post.

Richard United States

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