In addition he taught some advanced courses such as elliptical functions, hyperelliptic functions, and invariant theory. W Lorey, who was an undergraduate at Halle at the end of Wiltheiss' career, presents this rather disturbing image of his last lecture:
Bukod dito siya itinuro ng ilang mga advanced na kurso tulad ng tambilugin function, hyperelliptic function, at invariant theory. W Lorey, na noon ay isang undergraduate at Halle sa dulo ng Wiltheiss' karera, pagtatanghal na ito sa halip disturbing imahe ng kanyang huling sermon: