Can Janez Puhar (1814-1864), a Slovene priest and experimenter with the technique of ‘writing with light’, be considered the inventor of photography on a glass plate? Unfortunately, precedence for the invention of this process remains disputed, since several inquisitive and inventive men independently arrived at similar results in different parts of Europe (especially France) in the late thirties and the forties of the nineteenth century. Some might have been faster in making their findings public, others more skilful or even cunning in presenting the facts. The more modest and less forceful Puhar is certainly among those who gave substance to their vision in the earliest period and cannot therefore be denied a pioneering role in the birth of the new medium. Puhar announced his invention in Slovene in a report published in Carniolia in 1841. Two years later, in 1843, he informed the rest of Europe in German about his sensational achievement: a report with a description of his photographic process was published, again in Carniolia (Neu erfundenes Verfahren, transparente Heliotypen aus Glassplatten darzustellen) as well as in the Graz Innerösterreichisches Industrie- und Gewerbe Blatt. These publications clearly did not reach Paris, since the father of photography on a glass plate for the French is Abel Niépce de Saint Victoir, who informed the French Academy about his invention in 1847, and published the process itself the following year. Puhar’s precedence is contentious merely because the Paris Académie nationale agricole, manufacturiére et commerciale only in 1852 awarded him a diploma and title of ‘inventor of photography on glass’.