Pope John XXII issued a bull in 1326 CE that directly
attacked the use of the pendulum or any other dowsing
tool used for any purpose whatsoever. The pope and the
Vatican claimed that the pendulum-wielding diviner got
the answers straight from the Devil. This edict led to
other restrictions, which brought about the persecutions
and burnings of so-called Witches during the Burning
Times of the Inquisition in the Middle Ages and the
Renaissance. Some figures for these murders estimate
that nine million people were killed. Since many of the
victims were the village midwives, healers, and dowsers,
the Church termed them all Witches and Pagans and
executed them. The last Witch was killed in Calvinist
Scotland in 1728 CE.
Martine de Bertereau, a Frenchman who lived during
the mid-1600s, was a highly successful dowser for coal
mines. In fact, he found one hundred fifty such mines
before he was condemned by the Church and imprisoned
for life. However, good dowsers for water, coal, and
metal were so important to the existence of communities
that it was impossible for the Church to suppress them
all. The townspeople were not about to turn any dowser
over for execution and lose their economic edge.
After the persecutions topped, pendulums and other
dowsing tools were used more openly. However, for a
long time they doubled as tools of a guild trade, which
curtailed suspicion. An example of this, which still
survives today, is the carpenter's plumb bob. There is a
science museum in South Kensington, London, that has a
unique collection of tools used by the guilds in the
seventeenth and early eighteenth centuries. Among
these items is an engraving of two men holding dowsing
rods and a third man with a large pendulum.