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.

Historian 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."

A couple of weeks ago I wrote a blog post about the Turkish discovery of a 4000-year-old scalpel made of obsidian, along with skulls that had clearly been operated on. Since then I've managed to track down the director of the excavation, Onder Bilgi, at his dig site in Ikiztepe near the Black Sea. He gave me some more information about the find and sent me some photos, so here's an update.

Bilgi told me that life in the early Bronze Age settlement of Ikiztepe was relatively sophisticated. The inhabitants lived in rectangular log houses with courtyards and ovens in front, and they were skilled in metallurgy. They mined copper in the local mountains, then alloyed it with arsenic to make weapons, tools, jewellery and religious symbols. During 37 years of excavations, Bilgi's team have found items such as loom-weights and spindle-whirls used in textile production, bone piercers, flintstone and stone tools, copper pins, small stone hand axes, and fragments of pottery bowls, jugs, jars, beakers, tea pots and pitchers.

The researchers have also gained an insight into the spiritual life of the villagers. For example, they found a huge copper alloy spearhead, 58 centimetres long, next to a circular clay platform with a hole in the centre. Bilgi thinks this may have been a ceremonial platform and that the spearhead was used in some kind of ritual performance. Other finds include a range of abstract religious symbols, such as plaques and pendants. The plaques are decorated with spirals, or bulls' horns, while the pendants are carved into crescent or disc shapes, probably representing the Moon and the Sun, or into female figures. "It is well-known that Anatolia was the homeland of mother goddess and bull cults," says Bilgi.

So what about the surgery? It turns out Bilgi's team has found two scalpels, which are each about four centimetres long and double-sided (see top photo). Each is still incredibly sharp: "they would still cut you today," says Bilgi. In a graveyard on a nearby hilltop, the researchers found 700 skulls, of which 14 appear to have been operated on. A very sharp tool (Bilgi reckons obsidian would have been the only material around at the time that was sharp enough) has been used to cut rectangular openings in the skulls. Bilgi says that the surgery appears to have been done for medical reasons such as relieving a build-up of blood during a brain haemorrhage, removing a tumour, and fixing up a head injury. The skulls show signs of healing, so the patients clearly survived, at least for a few years.

You can read more about all this in my interview, published in this week's New Scientist.

Back in March, I travelled to Los Angeles to participate in an event dedicated to the Antikythera mechanism, held at the beautiful Getty Villa (pictured). I spoke along with Jim Evans of the University of Puget Sound in Washington. He is an expert in the history of astronomy, and author of The History and Practice of Ancient Astronomy, which came in very useful when I was writing Decoding the Heavens.

It turned out to be a fun evening. We discussed the history of research on the mechanism, as well as the latest ideas on what it was, who might have made it and why. Evans also summarised some new research he and his colleagues had just published on the mechanism in the Journal for the History of Astronomy. Very briefly, the device has (among other things) a zodiac dial on the front, on which pointers moving at varying speeds were thought to show the varying movements of the sun, moon and five known planets through the sky. Evans' measurements of the 360 divisions on this dial show that they were unevenly spaced, in quite a deliberate way. He concludes that the movement of the sun was represented not with a pointer moving at varying speed as previously thought, but with a pointer moving at constant speed around an unequally divided dial. Although this might sound quite geeky, this finding was completely unexpected and has some fascinating implications, which I'll be writing about very soon.

Anyway, I'm telling you all this now because the lovely people at the Getty Villa have just posted a video of the March event, which was called Tracking the Cosmos: The Technology of the Antikythera Mechanism. You can watch it here.

When British-born physicist Derek de Solla Price decided to teach himself the history of science in the late 1940s, he didn't mess around. He acquired a full set of the Philosophical Transactions of the Royal Society (supposedly for the library of Raffles College, Singapore, where he had just taken up a teaching position) and used them as bedtime reading.

Starting with the first volume from 1665, he worked his way through the heavy journals, placing the finished volumes into neat, chronological piles on his bedside shelves. Then he noticed something strange. Though each stack covered the same number of decades, each pile was twice as tall as the one before - in effect forming an exponential graph against his bedroom wall.

Price raced to check modern journals in various fields of science and found that the same relationship held. By counting the number of papers published in journals, it was possible to describe mathematically the accumulation of scientific knowledge. Science was accelerating exponentially over time.

Thanks to this bedside observation, Price became fascinated by the measurement and progress of knowledge. He went on to pioneer research into the 2000-year-old Antikythera mechanism (see chapters 4 and 5 of my book, Decoding the Heavens). But he also founded an entire field of research - scientometrics, or the science of science itself. He is best known for his 1963 book, Little Science, Big Science, which explored the incredible expansion of science. There's also a list of his publications here.

Among other things, Price concluded that science had grown by five orders of magnitude (more than 16 doublings) since the formation of the Royal Society, meaning that "80 to 90 per cent of all the scientists who have ever lived are alive now".

He also showed that the pattern of recent citations among the world's scientific papers could reveal areas where research was actively progressing, not to mention the relative importance to science of particular journals, authors, institutions and even countries. And he declared the secret of distinguishing science from non-science: the higher the proportion of citations of newer papers (those less than five years old) compared to old ones (more than 20 years old), the more likely that the article is scientific.

Historians were a little sniffy about Price's quantitative approach, but scientists loved it. Price himself believed he was uncovering universal truths about the nature of knowledge and where it was taking humanity. Little green aliens coming to Earth would understand the Planck constant, the velocity of light, or the wave equation no matter how much they differ from us, Price mused. He felt that they would surely also recognise his scientometrics.

Price (pictured with his model of the Antikythera mechanism) died in 1983. But his scientometrics is still going strong. An article in the Independent yesterday (basically a rewrite of a column by Harvard postdoc and science writer Samuel Arbesman in the Boston Globe last month) describes how Arbesman has been using scientometric techniques to address the question of whether science is getting more difficult.

Arbesman analysed research into mammalian species, asteroids and chemical elements by plotting the average size of new discoveries over time. He assumed that the smaller species and asteroids are, the harder they are to find, and that for elements the reverse is true.

He found that in every case, the ease of discovery is going down over time, not just in a linear fashion, but exponentially. In other words (in these simplified examples at least) it is becoming exponentially more difficult to make new discoveries. "To find a slightly smaller mammal, or a slightly heavier chemical element, you can't just expend a bit more effort," says Arbesman. "Sometimes you have to expend orders of magnitude more."

This doesn't mean that science is slowing down, however. As Price originally pointed out, the number of scientists is increasing exponentially too. Funding levels have also been rising fast, especially for fields such as particle physics and medical research. And in some areas, exponential increases in computer processing power are also keeping the discovery rate high.

That last point is something that Price would have appreciated. Perhaps because of his work on the ancient Antikythera mechanism, he was fascinated by the potential of computers. Back in the early 1980s, when most modern computers were still slow grey boxes with the simplest of circuitry and just a few kilobytes of memory, he predicted that they would become the next technological driver of knowledge.

In fact, he reckoned that the world was entering a "computer age", in which networks of three-dimensional computer chips would allow machines to jump to conclusions and to think creatively, just like people. We'll have to wait and see whether than particular prediction comes true.

In the news today is the discovery of "Britain's oldest house". Found in Scarborough, North Yorkshire, it is estimated to have been built in 8500 BC.

But I prefer another story, which is getting much less attention, about the discovery of a 4000-year-old scalpel blade made of obsidian. Hürriyet News reported yesterday that it was found by archaeologists excavating a site called Ikiztepe Village in the Black Sea province of Samsun, in modern day Turkey.

In charge of the excavations is Istanbul University's Onder Bilgi. He says that the scalpel would have been used in ancient brain surgery.

Intriguing... Yesterday's Hürriyet article doesn't say why Bilgi believes the blade was a scalpel but a small amount of digging turns up an earlier report from the dig site, published on 28 July, which says that 8 out of 690 skulls discovered at a graveyard on a high hill near the village showed "traces of surgical operation".

Actually this isn't as far-fetched as it sounds. There are records of neurosurgery from Babylon and Egypt, using obsidian blades, from as far back as 3000 BC. And skulls bearing traces of centuries-old brain surgery have been found in Europe, Africa, Asia and North and South America. The earliest trepanned skulls date from the Neolithic stone age (see main picture, of a Neolithic girl's skull now held in the National History Museum in Lausanne, France; she survived the surgery).

In the 2005 book Textbooks of Operative Neurosurgery, in a chapter about drills in neurosurgery, Trimurti Nadkarni and Atul Goel write that there would have been three main techniques for getting through the skull - scraping, trepanning and cutting. In the earliest examples, a sharp-edged flint scraper or knife would have been used to make a circular or rectangular groove in the skull.

In ancient Peru, knives of bronze or obsidian were used. The wound was covered with a shell, a gourd, or even a piece of gold or silver. More recently, surgeons would have used a bow drill, made of springy wood with a leather thong wound around it.

So why obsidian? It's a naturally-occurring volcanic glass. It is formed when volcanic lava with a high content of silicon dioxide (silica) cools rapidly. The high silica content makes the lava very viscous, meaning that sizeable mineral crystals can't form before the magma cools. The absence of crystals in the glass means that when it breaks, the fracture surface is very smooth, with extremely sharp edges.

Obsidian was used for ancient projectile points and blades, including a very nasty Mesoamerican weapon called a macuahuitl, which was a 3 to 4-foot-long wooden club, with obsidian blades embedded in it (see pic). It was also polished to create early mirrors.

In fact obsidian blades are sharper even than surgical steel blades, so some modern surgeons advocate using obsidian scalpels today. A 1993 study on rats showed that cuts made with obsidian blades initially formed narrower scars, and healed quicker, than cuts made with surgical steel scalpels. Unfortunately such blades are not generally approved for use on humans, so it looks like we will be sticking with steel scalpels for a while yet.

Wow. I just got back from Sci Foo camp, a meeting of over three hundred people from all areas of science held at the infamous Googleplex in Mountain View, California. Whereas most science conferences tend to be focused around a particular topic, this was an unconference (inspired by similar events held in the technology industry), organised by Google, Nature and O'Reilly Media. There was no theme, no schedule, and no rules particularly except that we were encouraged to attend sessions that we knew nothing about, and talk to people we didn't know.

As well as scientists from all areas there were lawyers, journalists, bloggers, filmmakers and philosophers. History of science was also well represented, with attendees including Will Noel of the Archimedes Palimpsest project, Tilly Blyth, curator of computing at the Science Museum, Nigel Warburton, creator of the excellent Philosophy Bites podcast and Bonnie DeVarco, who for many years was chief archivist for the Buckminster Fuller archive, but is now involved in exploring visualisation technologies. There were also plenty of demos, including a lego model of the Antikythera mechanism made by Andrew Carol, which I'm hoping to write about in a future post.

The result was a fascinating weekend - I ended up in discussions about everything from how virtual reality technologies will affect children's brains, to the end of gravity as we know it. I blogged the event for New Scientist, so rather than repeat myself, here are links to all my posts from the meeting:

Lego to loo seats: an unconference at Google HQ

Are you ready for life in world 3?

Evolution of music and a dancing cockatoo

Rewriting gravity over a tuna roll

And here are some other attendees' posts that I enjoyed:

Letter from SciFoo: The joys and sorrows of the unconference (Carl Zimmer)

Correspondent's diary: Around the campfire (The Economist)

Sci Foo 2010 Un-conference at Googleplex (Nigel Warburton)

Even more links are collected here.

Just a quick post to let you know about a new web page dedicated to the Antikythera mechanism - in particular the work of curator and mechanic Michael Wright (pictured). He spent many years studying the surviving pieces of the Antikythera mechanism, and built a working model that is pretty much universally recognised as a work of genius in itself. Now physicist and science historian Fabio Soso has collected together various material including papers, talks and interviews. Wright doesn't have his own website, and sometimes his work doesn't get as much media coverage as other research on the mechanism, so Soso says he has created the web page to make sure that Wright gets full credit for everything that he has done. Highlights of the collection include a beautiful computer animation of the gearing inside the Antikythera mechanism, which I've written about here.)

There's a fascinating talk up on the TED site this week by Dimitar Sasselov, a Harvard astronomer working on NASA's Kepler telescope, which is searching the skies for planets similar to our own. The telescope was launched in March last year. Until now, most of the planets spotted outside our solar system have been very large and orbiting very close to a star - nothing like Earth - just because those are easier to spot. We didn't have any idea how many Earth-like planets might be out there. And these are the ones that most people are interested in because they've got the best chance of being habitable...

The Kepler team announced their first results in January this year, but didn't include information on Earth-like planets. So Sasselov gives the first glimpse of what might be out there in his talk, which was given earlier this month and posted (I think) yesterday. He emphasises that most of the finds so far are candidates and will need to be confirmed with further tests (so far the mission has officially confirmed only 5 planets). But what's interesting is the distribution of sizes of the planets being found. About half-way through his talk, Sasselov shows a chart with about 250 planet candidates categorised by size, of which about 140 are Earth-sized (ie with a diameter less than twice that of Earth).

"The statistical result is loud and clear," he says. "Planets like our own Earth are out there. Our own Milky Way galaxy is rich in these kinds of planets."

He says that now we're starting to identify such planets, we can go on to study their conditions and chemistry to work out which may be capable of harbouring life like our own. He also estimates from the numbers so far that our own galaxy may contain 100 million habitable planets. He thinks Kepler will be able to confirm discovery of at least 60 of these within the next 2 years.

For the rest of his talk, Sasselov turns to synthetic biology research that he says goes hand in hand with the search for habitable planets. For example, he describes work in the lab of Jack Szostak. Researchers there have been looking at environments that might be found on Earth-like planets, and found that in conditions "with some liquid water and some clays", naturally available molecules can spontaneously form bubbles with cell-like membranes.

"There is immense, powerful potential in life in this universe," Sasselov concludes. "Especially now we know that places like the Earth are common."

"Our sensations and astonishment are difficult to describe as the better light revealed to us the marvellous collection of treasures: two strange ebony-black effigies of a King, gold sandalled, bearing staff and mace, loomed out from the cloak of darkness; gilded couches in strange forms, lion-headed, Hathor-headed, and beast infernal; exquisitely painted, inlaid, and ornamental caskets; flowers; alabaster vases, some beautifully executed of lotus and papyrus device; strange black shrines with a gilded monster snake appearing from within; quite ordinary looking white chests; finely carved chairs; a golden inlaid throne; a heap of large curious white oviform boxes; beneath our very eyes, on the threshold, a lovely lotiform wishing-cup in translucent alabaster; stools of all shapes and design, of both common and rare materials; and, lastly a confusion of overturned parts of chariots glinting with gold, peering from amongst which was a mannikin. The first impression of which suggested the property-room of an opera of a vanished civilization."

These are the words of archaeologist Howard Carter, describing his first glimpse inside Tutankhamun's tomb after he discovered it in 1922. The treasures within had been undisturbed for 3,300 years.

This discovery is now one of the most famous in all of archaeology - the only intact royal tomb that has ever been found from ancient Egypt. But the details of what Carter found are surprisingly little known. In all, Carter found 5,398 items, so many that it took him 10 years to catalogue them all. Some, like Tut's iconic gold burial mask, are instantly recognisable. But the majority have never been properly studied and published, and are unfamiliar even to experts. Carter died in 1939, just seven years after his excavation ended, and before he could fully publish his findings. The sheer size and importance of his haul seems to have discouraged other scholars from tackling it.

The notes from Carter's excavation, including 3,500 densely-written note cards, more than 1000 photographs taken by Carter's colleague Harry Burton, as well as Carter's diaries and journals, are now held in the Griffith Institute in Oxford. I've just written this article in The Observer about an effort by Jaromir Malek, head of the Griffith Institute, to make all of these materials available online. He and his handful of staff have had to do it in their spare time because no one would fund the project, but after 15 years they have finally finished, and the last pieces will be scanned, transcribed and posted in the next few months.

The result is a really stunning website called Tutankhamun: Anatomy of an Excavation. You can browse the objects from the tomb - some of my favourites include this leopard-skin cloak with golden head and silver claws, this model boat, and this brilliant folding bed. Or you can search for a specific item - type in "mummy" for example (then click on "King's mummy") and you'll find 68 photos of Tut's mummy taken at various stages of the unwrapping process. I also love Burton's eerie photos of the undisturbed tomb.

Malek says he wants to put "moral pressure" on Egyptologists, to encourage them to study this immensely important collection of objects. Researchers still need to study the objects themselves of course, most of which are on display in the Museum of Egyptian Antiquities in Cairo. But the Carter archive includes information that can't be gleaned from looking at the objects today. He recorded exactly where each item was found within the tomb for example. And he saw them in the best possible condition - many of the finds, especially those made of organic material, have decomposed since they were removed from the tomb. Andre Veldmeijer of the PalArch Foundation in Amsterdam used the website in a recent analysis of the footwear found in Tutankhamun's tomb. One pair of leather sandals, delicately embellished with gold leaf and coloured beads, is shown perfectly preserved in Burton's potographs, yet Veldmeijer says his visit to see the shoes in the Cairo museum revealed an oozing black mess. He describes the online archive as "one of the best things in Egyptology".

But the site isn't just for researchers. Malek says he hopes project will bring the forgotten details of the tomb to as many people as possible. "We felt this was important because the discovery is so well-known," he says. "This doesn't belong to Egyptologists only, or even to Egypt only. Everybody should have the right to see what's there."

[Thanks to the Griffith Institute for the above photo, which shows Carter supervising the removal of objects from the tomb in 1922.]

UPDATE:

As well as my Observer article mentioned above, which discusses how researchers are now using the archive to make new discoveries about the tomb, you can also listen to my interview with Jaromir Malek on today's Guardian Science Weekly podcast.

Did Archimedes use mirrors to power steam cannons when fighting against the Romans in the third century BC? That's the suggestion of Italian engineer Cesare Rossi, who has reconstructed how the solar-powered weapon could have worked. The result is ingenious, but historians of ancient technology are sceptical that it bears any relation to anything that Archimedes actually used.

I've just written a story on this for New Scientist, which includes a graphic showing Rossi's suggested design for the cannon. I didn't have room to put much into that story about what other scholars think of the idea, so I've discussed their reactions in a bit more detail below.

 Archimedes is famous for supposedly inventing all kinds of wondrous war machines when the Romans laid siege to Syracuse, Sicily, where he lived. One of the most well-known stories, that he used mirrors to focus sunlight and set fire to enemy ships, seems extremely unlikely, even though modern reconstructions have shown this technique to be theoretically possible.

First, there aren't any sources from Archimedes' own time that tell this story. Sceptics also complain that to keep the sun's rays focused on a moving ship you would need to constantly change the mirror's curvature. And such fires would start very slowly, so those on board would presumably be able to extinguish them.

Rossi believes that another Archimedes legend throws new light on the burning mirror story. Several historical sources, including Petrarch in the 14th century and Leonardo da Vinci in the 15th century, wrote that Archimedes invented a steam-powered cannon, in which pressurised steam at the base of the gun forces a projectile out of the barrel at high speed. And the Greek historian Plutarch (46-120 AD) wrote that during the siege of Syracuse, the Romans saw something that was similar to a pole protruding from the city walls, and ran away shouting: "Archimedes is going to throw something on us now." Rossi says that could be a reference to a cannon.

Several teams have previously looked at whether or not this might work. But Rossi is suggesting a slight twist to the idea. At a conference on Archimedes in Syracuse last month, he suggested that mirrors focusing the sun's rays could have been used to heat the steam cannons. The cannons would then have been used to set fire to ships by hurling hollow projectiles filled with an incendiary fluid, perhaps a mix of sulphur, liquid bitumen, pitch and calcium oxide.

Rossi says this is a much more plausible use of burning mirrors than trying to set fire to distant ships. He points out that mirrors are used today to heat fluid to high temperatures in some applications of solar energy. He calculates that a cannonball measuring 20 centimetres across would have weighed around 6 kilograms and could have been fired from the gun at 60 metres per second, with a range of around 150 metres.

It's all intriguing speculation. But historians are not particularly impressed, mainly because, just as with the burning mirrors, there is no direct mention in the historical record of Archimedes inventing a steam cannon until many centuries after his death. Tracey Rihll, an expert in ancient science and technology from the University of Swansea, calls Rossi's idea an "interesting hunch" but says that to make a convincing case, Rossi would need to explain how writers such as da Vinci could have found out about Archimedes' invention. "Leonardo did have access to ancient texts," she says. "There is a paper about his thoughts on colour being directly influenced by the rediscovery of Aristotle's On Colours, for example. But a case needs to be made for something similar here."

Rihll also points out that many of the details that Rossi uses in his calculations are very different from the ones described by da Vinci. For example, da Vinci described a 25 kg solid iron ball, whereas Rossi considers a 6 kg ball made of hollow clay.

Another expert, Serafina Cuomo at Birkbeck College, University of London, has similar concerns. Reconstructions demonstrate a "technological possibility" she says, but don't constitute historical evidence: "We have a perfectly good explanation for later accounts that attribute steam cannons to Archimedes, and that is that Archimedes became a quasi-mythical icon of the scientist capable of constructing incredible weapons, and that in later medieval times some new weapons, ie cannons, did come onto the scene. Put the two together, and you have the story." Rihll agrees: "Archimedes' name attracts inventions to itself like moths to a flame." 

Rossi admits that showing how the steam cannon could have worked "doesn't mean that it happened". But he adds that it is a much more likely use of burning mirrors than setting fire to ships directly. He doesn't have the funds to build a working model of the solar-powered cannon, but says that if anyone is interested, he can provide the technical drawings. 

So, whether or not Rossi is right about the steam cannon, what other impressive weapons might Archimedes have employed against the Romans? The Greeks were certainly handy with a catapult. "Those of Archimedes' time could outperform [Rossi's steam cannon] in every department: payload weight, range, ease of use, reliability, health and safety," says Rihll. The idea that Archimedes invented a giant claw with which to attack ships is also plausible - Rihll believes that this is the most likely explanation of the pole-like device described by Plutarch. According to Cuomo, the closest invention to a steam cannon in ancient sources is a mention of a compressed air-operated catapult in Philo of Byzantium.