"I DOUBT This!" – the commentary on the margin of a lecture transcript from the summer semester of 1885 reads as if it were an exclamation. Friedrich Blanck uses capital letters, equality and exclamation marks to reinforce his doubt. The author was a student at the Friedrich-Wilhelms-Universität (today's Humboldt-Universität) in Berlin.
© Universitätsbibliothek der Humboldt-Universität zu Berlin, Historische Sammlungen – Signatur: Hdschr. Koll 290 / Stiftung Humboldt Forum, digitale Reproduktion: Jester Blank GbRG