Three years after taking up the appointment in Clausthal, he became professor of mechanics at the Technische Hochschule in Aachen. This appointment had much to do with Klein .
Tatlong taon matapos ang pagkuha ng appointment sa Clausthal, siya ay naging propesor ng mekanika sa Technische Hochschule sa Aachen. Appointment na ito ay marami ang gagawin sa Klein.