Our modern world is obsessed with acronyms. The ancient and esoteric art of dowsing, for example, is now presented as the BPM Technique, and has a small but faithful following in the mining industry and other related sectors in the world of commerce. The "Bio-Physical Method", it seems, is what they call it now.
Dowsing, or divining, consists of holding a pair of outstretched rods - traditionally a forked branch of hazel or willow, but a wire coat-hanger or a pair of knitting needles will do in an emergency - which when manipulated by the diviner, twitch or incline towards a place where lies a concealed spring or a metallic lode.
If and how dowsing works has been hotly debated over the years. In the majority of tested cases the results have proved almost entirely negative, but a few dowsers are successful often enough for the phenomenon not to be totally dismissed as chance, coincidence or subterfuge.
Insofar as explanations have been sought, most focus on the assumption that dowsers are for some reason unusually sensitive to the Earth's magnetic field, and pick up very small changes in it caused by water or metal underground. This theory suggests that when such persons detect a magnetic anomaly, it sends a signal to the dowser's muscles, which experience a small contraction, causing the lightly-held dowsing-rod to deflect.
Other experimenters claim that dowsers respond to anomalous electrical fields in the vicinity, which they say affect their blood pressure and their pulse rates.
Adherents to the former view received a boost some time ago when researchers at the Californian Institute of Technology announced that they had identified in human brains tiny crystals of magnetite, the iron oxide which helps migrating birds to navigate.
Experiments are still going on to discover if this might give humans an unconscious and rudimentary directional sense, similar to that enjoyed by homing pigeons.
Dowsing enthusiasts, however, say this new discovery may well be the basis of their gift. The idea is that some individuals may be more generously endowed with magnetite than others, which, they maintain, would explain why some people are dowsers while others achieve no reaction whatever.
Critics, on the other hand, remain adamant that successful dowsing owes more to a thorough knowledge of the local geology than to any innate ability to detect magnetic or electrical anomalies in the vicinity. Their attitude could best be summed up in the forthright words in another context of the American journalist H.L. Mencken: "Nine times out of 10, there is actually no truth to be discovered - only error to be exposed."