Franz Kessler


Franz Kessler was a portrait painter, scholar, inventor and alchemist living in the Holy Roman Empire during the 16th and 17th centuries.

Writing

He wrote a number of books and pamphlets: a book on stoves, on making sundials, on using a "sector" or "proportional instrument", and on using "Napier's bones" -- among other works.

Painting

In the 1620s and 1630s, he was a portrait painter in Cologne, Germany.

Inventions

He wrote a book called Unterschiedliche bisshero mehrern Theils Secreta oder verborgene, geheime Kunste, which was published in Oppenheim in 1616. The first five chapters of this book deal with communicating via a crude Aldis lamp.
In the same year he built an improved diving bell.