He was promoted to extraordinary professor there in 1866 and taught at the University until winter semester 1868-69 when he accepted an appointment at Greifswald. Fuchs also held a second post in Berlin from 1867 when he was appointed as professor of mathematics at the Artillery and Engineering School.
Siya ay itaas sa mga katangi-tangi propesor doon sa 1866 at nagtuturo sa University hanggang sa taglamig semestro 1868-69 kapag siya tinanggap ng appointment sa Greifswald. Fuchs din gaganapin ang isang ikalawang post sa Berlin mula 1867 kung kailan siya ay hinirang bilang propesor ng matematika at ang artilerya at Engineering School.