Hero of Alexandria, on the making of automata

The technical works of antiquity are not well known, not least because modern technical knowledge is often necessary to understand them.  For instance a reading of an alchemical work may well baffle anyone without a Chemistry degree!  So … they go untranslated and unread.

Four years ago I listed the works of the engineer, Hero of Alexandria, here.  In this I included a reference to a translation of his work Peri automatopoietikes, on making automata: Susan Murphy, “Heron of Alexandria’s On Automaton-making“, in: History of Technology 17 (1995), 1-46.  At the time I was quite unable to locate this journal, or the translation, so the matter went no further.

A correspondent asked about this a couple of weeks ago, and then – mirabile dictu – was able to obtain a PDF by mysterious means.  The PDF originated in Sydney University library, from whose catalogue I learned that it was published in London by Mansell.  It seems that the “journal” is actually a series of books, published under the imprint of Mansell of London, by none other than Bloomsbury Press.  It is a series aimed at engineers, and so naturally shelved away from the sort of material with which we are familiar.  In fact the series seems to be widely held, and it is merely the rather generic title which makes searching difficult.

Dr Murphy’s article is 44 pages long – can that really be the size of the volume? – and itself is full of interest.  I learn that the work is illustrated in the manuscripts, with diagrams that may go back to the author but are supposedly corrupt.  The critical edition of the text does not trouble to reproduce them – no doubt because of the difficulties of printing coloured photographs – but instead has drawings by a modern author, based upon them.

The work describes the construction of  two automata, as an example of two types of automaton.

The first is a mobile shrine of Dionysus, complete with little figurines of the god and his worshippers.  This rolls of its own accord on a wheeled base to a specified point, at which the figurines enact a scene of sacrifice and pouring libations.  It then returns to the original point.

The second is a minature theatre, which stages a complete tragedy when activated.

Both types of automaton rely on a descending counterweight and various cords and axles – essentially upon clockwork.

The opening section of the work, before the technical receipes, is itself rather interesting.

ON AUTOMATON-MAKING

Book I

1. 1. The study of automaton-making has been considered by our predecessors worthy of acceptance, both because of the complexity of the craftsmanship involved and because of the striking nature of the spectacle. For, to speak briefly, every facet of mechanics is encompassed within automaton-making, in the completion of its several parts.

2. These are the topics to be discussed: shrines or altars of appropriate size are constructed, which move forward of themselves and stop at specified locations; and each of the figures inside them moves independently according to the argument of the arrangement or story; and then they move back to their original position. Thus such realizations of automata are called mobile.

3. But there is another kind, which is called stationary, and its function is as follows: a toy stage with open doors stands on a pillar, and inside it an arrangement of figures has been set up in line with some story.

4. To begin with, the stage is closed, and then the doors open by themselves, and the painted representation of the figures is displayed. After a little while the doors close and open again of their own accord, and another arrangement of figures, sequential to the first one, appears. Again the doors are closed and opened and yet another arrangement, which logically follows the one before it, appears; and either this completes the planned story, or yet another display appears after this one, until the story finally is finished.

5. And when the figures which have been described are shown in the theatre each one can be shown in motion, if the story demands; for instance, some sawing, some chopping with the adze, some working with hammers or axes – making a noise with each blow, just as they would in real life.

6. Other movements can be effected below the stage; for instance, lighting fires or making figures which were not visible at first appear and then disappear again. Simply, anyone can move the figures as he chooses, without anybody being near them.

7. But the mechanism of the stationary automata is safer and less risky and more adaptable to every requirement than that of the moving ones. Older generations called such feats of craftsmanship miraculous because they offered an amazing spectacle.

8. Therefore, in this book I am going to write about moving automata, and set out my own complex scenario, which is adaptable to every other scenario, so that someone who wanted to offer a different presentation would not lack anything for the implementation of his own scenario. In the following book I talk about stationary automata.

Well worth hunting out this volume, if you have even the slightest interest in ancient technology.

The Antikythera mechanism — return to the wreck site

The Guardian reported on 2nd October:

Between 1900 and 1901, the sponge divers retrieved a string of stunning antiquities, including weapons, jewellery, furniture and some exquisite statues. But their most famous find was a battered lump that sat unnoticed for months in the courtyard of Athens’ National Archaeological Museum, before it cracked open to reveal a bundle of cogwheels, dials and inscriptions.

It has taken scientists over a hundred years to decode the inner workings of those corroded fragments, with x-ray and CT scans finally revealing a sophisticated clockwork machine used to calculate the workings of the heavens (video).

Dubbed the Antikythera mechanism, it had pointers that displayed the positions of the sun, moon and planets in the sky, as well as a star calendar, eclipse prediction dial and a timetable of athletics events including the Olympics. …

But one of the most intriguing mysteries relates to the wreck on which it was found. What’s still down there?

The wreck lies in around 60 metres of cold, rocky, current-swirled water – not an easy place to visit. The sponge divers who salvaged its cargo worked in clunky metal diving suits with little understanding of the dangers of diving at such depth. By the time they abandoned their project, two of them had been paralysed by the bends, and one was dead. They left behind stories of abandoned treasures, including giant marble statues that rolled down the steep slope from the wreck and out of reach.

The undersea explorer Jacques Cousteau spent a couple of days at the wreck site in 1978 and brought up some precious smaller items, including some coins from the Asia Minor coast, which suggested that the ship sailed from there around 70-60 BC (probably carrying war booty from Greek colonies back to Rome). But even with their sleek scuba gear, Cousteau’s divers could spend only brief minutes on the seabed without risking the bends.

No one has been back since. Now, after years of negotiations with the Greek authorities, Brendan Foley, a marine archaeologist based at Woods Hole Oceanographic Institution in Massachusetts, finally has permission to dive at Antikythera. He’s working with Greek archaeologists including Theotokis Theodoulou of the Ephorate of Underwater Antiquities.

This week, the team begins a three-week survey using rebreather technology, which recycles unused oxygen from each breath and allows divers to stay deeper for longer. The aim is to survey the wreck site properly for the first time, to find out once and for all what has been left down there – and to check down the slope, to 70 metres depth or more, to see if those stories of runaway statues are true.

And, of course, what if there is further ancient technology just sitting there, unrecognised?