Daguerreotype
Invented by Louis-Jacques-Mandé Daguerre and introduced worldwide in 1839, daguerreotype was almost completely superseded by 1860 with new, less expensive processes yielding more readily viewable images. In the late 20th century, there was a revival of daguerreotypy by a small number of photographers interested in making artistic use of early photographic processes.
Franziska Möllinger
It is not very clear why Möliinger became interested in daguerrotypes but it may well have been because her brother Otto was also the editor of the local Solothurn news sheet which, on 4 April 1839, published a report on Daguerre's work. The "Solothurner Blatt" later reported on progress on daguerrotypes on 28 August 1839. In the December edition, Otto Möllinger reported on progress in even greater detail.