Technikatörténeti szemle 18. (1990-1991)

Árpád HORVÁTH Gábor Szilágyi: Daguerre. The Story of Discovering Photography (in Hungarian) 233 Árpád HORVÁTH Farkas Kempelen: The Mechanism of Human Speach and the Description of a Speaking-machine of the Autor (in Hungarian) 233 Gyula KISZELY Mária Sarudyová: Topography of the 19th C. Slovak Iron Metallurgy (in Slovakian) 234 István TRJNGLI Conrad Grau: Worlds Famous Academies of Science (in German) 236