He began lecturing at the University of Cambridge in 1978 , and retired in 2007 .
After graduation , Wallace worked for Rolls - Royce until 1971 , when he started an engineering firm .
Wallace began lecturing at the University of Cambridge in 1978 , and retired in 2007 .
After graduation , Wallace worked for Rolls - Royce until 1971 , when he started an engineering firm .