This is another of those posts I’ve been meaning to write for some time without knowing quite where to start. I’ve been given a kick start by a twitterer (Marcus Smith) and by a recent BritArch announcement of a dowsing ‘experiment’ (you must be a subscriber of BritArch to see the link!). The problem is that it’s such a huge topic, it’s difficult to know where to begin.

Personal experience

I’ll start of with a bit of personal history. In my early teens, I devoured every book in Letchworth library on Egyptology, followed by every book on archaeology in general. I was also interested in fringe archaeology, even then, so I was drawn to the Dewey Decimal System’s notorious class 001.9, ‘controversies’. It’s basically a catch-all for busy librarians who don’t know where to put pseudoscience but who know better than to lump it in with the genuine science it mimics. So, I would turn left on entering the library, past the card indices of authors, titles and subjects (and, in those days, it really was a physical card index in wooden drawers), and into the realms of Isis Unveiled, Chariots of the Gods and the like.

On one of those visits, a whole raft of books by T C Lethbridge had appeared. I was vaguely aware of the name, as he was an archaeologist who had excavated at a well-known Romano-British cemetery site in Guilden Morden, close to my home. These books – Ghost and ghoul (1961), Witches: investigating an ancient religion (1962), Ghost and divining rod (1963) and ESP: beyond time and distance (1965) – were about various matters on the occult side of things. Like many teenagers, I found the occult fascinating: perhaps there was secret knowledge that the Establishment was either unaware of or was keeping from the rest of us. This sort of fascination, I now understand, is all part of growing up, of learning how to be an individual, of discovering that there are no real authorities to whom we can turn for the answer to everything.

Yet here was a proper archaeologist discussing such matters. Some of it made intuitive sense to me and I was swept up in the rest of it. One of Lethbridge’s great discoveries was that he could dowse using a pendulum. Like a proper scientist, he conducted experiments. He found that the pendulum reacted to different materials if he varied the length of its string; he then found that as well as materials, the pendulum could be made to react to concepts (such as male, female, age and so on). He discovered that he could use the pendulum to determine the precise age of something (a site, an artefact, anything that he wanted to date). He also found – and this is where my teenage credulity was stretched to its limits – that it was possible to dowse for archaeological sites using a map: one did not have to travel to places to discover new sites (and, of course, date them with a precision that radiocarbon will never achieve).

Of course, I tried the technique. It didn’t work. I rationalised this (can one really rationalise the irrational?) as “it doesn’t work for me“: it clearly worked for Tom Lethbridge. After all, he was a retired archaeologist and I was determined that I would become one, too. Archaeologists were people I admired and trusted. The curator of my local museum, John Moss-Eccardt, was an archaeologist who ran evening classes and a museum club that I attended. Archaeologists were serious people who knew their stuff, so Tom Lethbridge just had to be on to something.

The view from the mainstream

Professional archaeologists have always been a bit ambivalent about dowsing. Here’s the entry from Warwick Bray and David Trump’s (1970) Dictionary of archaeology:

dowsing A technique for discovering buried features or materials by the use of a Y-shaped hazel wands, bimetal strip or the like. The scientific principle behind it is not understood and indeed by many people its validity, at least for archaeological prospecting, is doubtful.

“Scientific principle“? Do the authors believe it or not? There seems to be some fence-sitting going on here. A little over a decade later, Lesley Adkins and Roy Adkins’s A thesaurus of British archaeology (1982) has this to say:

Dowsing is the same procedure as water-divining and can be used to located buried archaeological features. The success or failure of the method depends on the talent and skill of the dowser, who usually uses some form of simple instrument such as a Y-shaped piece of wood which is held in the hands and whose movements indicate the position of the features as the dowser walks over them. Once the position of a site has been located, it can also be surveyed by dowsing. A grid is laid out over which the dowser walks, so that the results of the survey can be plotted on to a scale plan of the area.

So, it works then? It’s all to do with the “talent and skill of the dowser“, which is an assertion that my teenage self was happy to contemplate. What about more recent texts? Colin Renfrew and Paul Bahn’s Archaeology: theories, methods and practice is currently the most popular undergraduate textbook of archaeology: they must say something about dowsing. And indeed they do:

In concluding this section on subsurface detection, we may refer in passing to a controversial technique that has a few followers. Dowsing (in the U.S. witching) – the location of subsurface features by holding out a twig, copper rod, coathanger, pendulum, or some such instrument and waiting for it to move – has been applied to archaeological problems for at least 50 years, but without being taken seriously by most archaeologists.

Aha! A note of scepticism. The writers go on to describe an experiment carried out in Northumberland, in which sceptical archaeologists took part in the survey of buried church foundations and were convinced by its results. Some of the walls detected by dowsing were located, while other predicted walls were not located. Another experiment described by Renfrew and Bahn involved an attempt to locate a Romano-British pottery kiln, for which the results obtained by dowsing did not match those obtained by magnetometry: they do not say whether excavation was carried out to test the two techniques. Nevertheless, they conclude:

For the moment… until overwhelming proof of the validity of dowsing and other unconventional methods is forthcoming, archaeologists should continue to put their faith in the ever-growing number of tried-and-tested scientific techniques for obtaining data about site layout without excavation.

The greatest authority on archaeology for students nevertheless leaves open the possibility that “overwhelming proof” of dowsing’s ability to detect archaeological remains may one day be found.

More personal experiences

In 1999, I worked with members of the Chester Archaeological Society on a project to locate a warehouse on the banks of the River Dee that had been used during the eighteenth century to store Cheshire cheese before being shipped to London, which was becoming an important market for the product. The warehouse burned down in the nineteenth century and no trace of it survives on the site today; it had been the inspiration for Lewis Carroll’s grinning Cheshire Cat, which is said to have described the happy cats who sat on the quayside of the Cheese Warehouse, waiting for the mice who, attracted from the ships by the smell of cheese, would run up the tethering ropes of the ships into the cats’ ready paws.

We began the work by undertaking a resistivity survey in February/March 1999; this was inconclusive, but showed up some foundations that we could identify as part of a house known as Copfield House, which is first seen on a map of 1874 and which was demolished c 1979×81. A photograph of the back of the house taken in the 1960s bore a slight resemblance to a depiction of the Cheese Warehouse on an eighteenth-century painting of the port. Excavation in May of the same year revealed the foundations of the nineteenth-century house but nothing that could be recognised as part of the Cheese Warehouse. We returned to the site in 2000 to carry out more excavations in different areas, still with little success. One of the society members is a keen dowser, so he got out his rods and everyone soon began dowsing. Several people – myself included – got reactions on a bank on the western edge of the site, so we decided to dig there. Very soon, a stone wall was located. Another trench placed over an area where dowsing had suggested another wall should be located failed to locate it; it did, however, locate some small stone pillars on which the wooden joists for the raised floor of the warehouse were held.

So, what did the dowsing achieve? In my opinion, nothing. The one trench where a length of wall was found ran across a bank (which had apparently not existed in 1972), where the dowsing suggested that there ought to be a wall. I suspect that the bank misled us into identifying it as something piled up over the demolished warehouse wall. In fact, the top of the bank did not coincide with the position of the wall; nor was it on the line suggested by dowsing. The other walls “located” in this way proved not to exist.

To be concluded

I am currently working on a fascinating site with the Norton Community Archaeology Group, where I have identified what appears to be an early (‘formative’) henge of Neolithic date. The group has worked with a well known dowser on the site, and the next instalment of this blog will deal with their discoveries.