The thunder church
It must have been a spectacular sight, at the public demonstrations Jacob Uilkens organised as professor of agronomy. Under the watchful eye of farmers and villagers from the Marne area, north of Groningen, he placed a small tin of gunpowder in this wooden ‘thunder church’. Hanging just above it, coming down from the tower, was a copper wire.
Next, Uilkens generated electricity through a small electrostatic generator, until an artificial lightning bolt hit the brass knob on the tower. Then… boom! The hinged sides flew outward and the church collapsed.
After this, Uilkens repeated his test. However, this time he connected the knob on the spire and the ground using copper wire. Lo and behold: the church stayed untouched when it was hit by ‘lightning’.
These demonstrations, which took place mainly after 1815, were designed to convince the public of the blessings of lightning conductors. The principle had been discovered by Benjamin Franklin in 1752, but it wasn’t until the beginning of the nineteenth century that the first lightning rod was placed on a Dutch building. In 1837 the Martini Tower in Groningen got one too.
Uilkens and his colleague professor Theodorus van Swinderen wanted to inform the public of these developments. The demonstrations with the thunder church were part of this. They were successful too. Uilkens himself noted that ‘surely, in this province, more conductors have been placed on barns and mills than in any other country’.| Last modified: | 13 August 2021 3.34 p.m. |