Chemigram

[2] Johann Schulze is regarded as the first to obtain a chemigram-like image; in 1725, he produced such a work using opaque paper and a bottle of silver salts.

[2] In the 1930s and 1940s, the German Edmund Kesting and the French Maurice Tabard produced pictures by painting with developer and fixer on photographic paper.

He adopted the name chimigramme in French in 1958 (chemigram in English and Dutch, Chemigramm in German, chimigramma in Italian, and quimigrama in Spanish and Portuguese), the most widely accepted designation today.

[4] A chemigram is made by painting with chemicals on photographic paper and lies within the general domain of experimentation in the visual arts.

The possibilities can be multiplied by using materials from painting (such as varnish, wax, or oil),[2] These kinds of experiments are akin to those of Paul Klee, Max Ernst, and Antoni Tàpies.

Paolo Monti , 1970
First page of the Bayard album, photosensitization test, 1839, collection of the Société française de photographie
Josef H. Neumann Chemogramm *Traumarbeit* (1976)