[ . . . ] Today the small electric trolley in Lichterfelde was officially tested and approved at last. The only problem was, and still is, that the speed of the trolley cars has to be reduced in keeping with the regulations. The inspectors would only permit 20 km/h, whereas the cars, fully loaded with 20 passengers, reached 30 to 40 km/h even uphill! However, I think that people will get accustomed to the higher speed!
Source: Werner von Siemens, letter of May 12, 1881, to Professor Wiedemann of Leipzig, in Conrad Matschoß, ed., Werner von Siemens. Ein kurzgefaßtes Lebensbild nebst einer Auswahl seiner Briefe [Werner von Siemens: A Summary of His Life Together with Selected Letters]. Berlin, 1916, p. 691.
Original German text reprinted in Gerhard A. Ritter and Jürgen Kocka, eds., Deutsche Sozialgeschichte 1870-1914. Dokumente und Skizzen [German Social History 1870-1914. Documents and Sketches]. 3rd edition. Munich: C.H. Beck, 1982, p. 53.
Translation: Erwin Fink