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I was able to have Julius Campe assure me that he was not a typical book trader, one who only does business with the noble, the beautiful and the great and exploit a good economic situation. Rather, he also prints the noble, the beautiful and the great even under very unfavourable economic circumstances and really does not profit from this. When he heard such words, Börne listened keenly and they led him later to travel to Hamburg and to talk to the publisher of the “travel pictures” about publishing his entire writings.
Heinrich Heine, Ludwig Börne. A Memorial, 1839
The coordinate system of independent and dependent variables became a significant indicator of the industrial age. Time is often depicted on the x-axis and, dependent on this, the course of revenue and profit as well as exchange rates (Capital), changes in the size of the workforce (Factory) and transport services (Networks) are depicted on the y-axis.
The book trade also developed an interest in its own history in the 19th century. The records kept at book fairs were an important source of information here as they provided wide-ranging insights. The statistical analyses of the book fair catalogues were prepared meticulously, yet they were assessed with circumspection when they were published, as the example of Kapp shows. In times of war, some traders did not come to the fair, which is why the drop during the Thirty Years’ War in 1635 seems worse than it actually was.