During the early modern period, the divining rod turned into an all-purpose tool for divination: Dowsers claimed that they could find forgotten boundary stones, suitable sites for building, game in the exploited hunting grounds of the nobility, unoccupied spots in the churchyard, or even mistakes in history books. If you searched for hidden springs or mineral veins you did not even have to leave your study anymore: It was sufficient to hold the divining rod over a map. It would point out the spot where you had to dig. In 1692, the master dowser Jacques Aymar even managed to find a murderer who had escaped the law enforcement officers of Lyon. Even though the magical charlatanry of dowsing never went unchallenged the divining rod survived into the 21st century.
Whereas the early theoreticians of the divining rod had claimed that there was some mysterious connection between the rod and the materials you searched for, from the 17th century onwards the person of the diviner became more important. It was said that only especially sensitive persons were able to dowse. The 20th century witnessed a relative ‘democratization’ of the use of the divining rod: It was now claimed that you did not need any special kind of talent in order to work successfully as a dowser. All it took was a little concentration and one of the many, relatively cheap training manuals. Dowsing for supposedly healthy food – never mind what your doctor might say - seems to be the latest trend.
The key to the success of the divining rod or its more modern equivalent, the pendulum, is its very simplicity. The divining rod is the dilettante’s dream: It is cheap and can be handled by practically everyone, it requires hardly any training and no expert knowledge. Thus, the divining rod is the very opposite of a scientific instrument.
Professor Johannes Dillinger, Professor in History, among whose many research interests are the history of Witchcraft, Magic, and Folk Religion.