When Gutenberg invented the printing press he had different bins for the capital letters and small letters. He kept the capital in the upper part of his cabinet and the small letters in the lower part, hence the terms upper-case and lower-case letters. When the first printers would print pages they may occasionally run out of a letter and one ‘trick’ was to use another letter in its place. If you ran out of an ‘n’ you could use an upside down ‘u’. There is scholarly debate about whether this happened in Shakespeare’s Othello. One of the last lines is “Like the base Indian, threw a pearl away Richer than all his tribe”. Some scholars contend this is correct and that he is referring to the newly discovered American Indians. Other scholars contend that it was originally written “Iundian” which would be a Jewish reference and also makes sense to scholars.
(The Great Courses – Turning Points in Medieval History)