According to Luca de Samuele Cagnazzi 's unpublished autobiography La mia vita, the tonograph was made by Cagnazzi himself with his own hands ("colle mie mani") in 1841. He also wrote a short essay about how it worked and its purpose and this work was first written in Latin language and published under the name Tonographiae Excogitatio (1841), since Cagnazzi wanted its invention to be known in what it was then known as Germany. Subsequently, he translated his essay to Italian language on the occasion of the Third Meeting of Italian Scientists, held in Florence, where he presented his invention.