Franciszek Rychnowski (1850-1929) - niedoceniony geniusz, maniak czy obłąkaniec?

The article presents the forgotten figure of Franciszek Rychnowski, an engineer from Lviv, mainly relying on his own writings and press releases from the period. The text describes his pioneering technical activity in Galicia, especially in the field of heating and electrical engineering. As far as it was possible, the paper elaborates on the concept of the so-called electroid (or etheroid) - substance (or energy) which Rychnowski held responsible for all phenomena in nature, and around which he forged his own theory of the operation of the universe. The text includes the summaries of his talks, interviews, and more interesting reports on the alleged properties of this substance, as well as reactions to them.