Source: 87 Abbildungen Böhmischer und Mährischer Gelehrten und Künstler, in Kupfer gestochen und verlegt von Johann Balzer, Prag 1772/Wikimedia Commons, public domain
The discovery was made in the garden in Přímětice near Znojmo, where Diviš worked as a parish priest and conducted scientific experiments. The main function of the “weather machine” was to permanently balance the tension between the sky and the ground and avert the discharge itself.
The base of the machine was a horizontal iron cross mounted on a forty meter post. The arms of the cross were supplemented by additional poles with 12 metal boxes containing layers of iron filings and 400 metal spikes. The entire structure was connected conductively to the ground by three chains. The erection of the device took place on 15 June 1754 with it functioning as a lightning rod. Diviš made observations of the self-assembled device during every storm and wrote the results in a large treatise “On the Nature of Atmospheric Electricity,” which he dedicated to Empress Maria Theresa.
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