In the 19th century Sylvester described a surface for studying the number of real roots of a polynomial. Henrici later constructed a model of this. This is a modern version.
It was back in the 1872 Göttingen, Germany, at a meeting of the scientific society. Alfred Clebsch and Felix Klein each presented a model of a cubic surface. Our modern versions of these historical - nowadays quite famous - sculptures are the main figures in our photo.