Facts: - caption: robert liddell - successor: robert w. lyon - death date: december 2 , 1893 -lrb- aged 55/56 -rrb- - predecessor: william c. mccarthy - office: 31st mayor of pittsburgh - term end: 1881 - birth date: 1837 - term start: 1878 - name: robert liddell - image: robertliddellpittsburgh.jpg - birth place: england Based on these bullet points, write a short biography describing the life of robert liddell -lrb- pittsburgh -rrb- .
The answer to this question is:
robert liddell -lrb- 1837 -- december 2 , 1893 -rrb- was mayor of pittsburgh from 1878 to 1881 .