Seite - 106 - in Nikola Tesla and the Graz Tech

106 In the building industry, especially in bridge construction, technical progress was demonstrated by the use of iron. The first large bridges of the time were chain bridges, where the roadway between two brick chain houses was sus- pended by tensioned chains. An early example of this is the Emperor Ferdi- nand chain bridge (Kepler bridge) opened in 1833. It was regarded as a mira- cle, as an expression of modern building convictions and even found its way into the theatre through the farce ‘Die Bekanntschaft auf dem Glacis, die En- tführung auf dem Ruckerlberg und die Verlobung auf der Kettenbrücke’ (Ac- quaintanceship on the Glacis, abduction from the Ruckerlberg and betrothal on the chain bridge.) After all, this bridge – the Biedermeier period was not so conservative at all – is the most common of all the motifs of the Graz veduta painter Conrad Kreuzer. Kreuzer lived with his family near the bridgehead in Lend (on the right- hand side of the river). Not only did Kreuzer devote his artistic expressions to the new achieve- ments of technology. Carl Reichert and Joseph Kuwasseg also did this, and Vinzenz Reim captured the ‘Iron House’ in one of his paintings. This was built in 1847/48 on Murplatz (today’s Südtirolerplatz) according to the plans of Josef Benedikt Withalm. The cast iron skeleton of the upper floor of the building, which was erected as a café, is one of the very early interna- tional examples of the use of iron in building construction. Withalm had already caused a stir years earlier with the construction of the Coliseum, a ‘hall for all’. In 1843 the 21st meeting of German natural scientists and doctors took place in the Coliseum. Participants included the chemist, Justus Liebig, the founder of mathematical physics, Andreas Ettinghausen, and the railway builder, Carl von Ghega.