He was a lawyer in Rochester, New York.
From the Wyoming County Times, Warsaw, NY, June 23, 1892: Mr. D. Clinton Barnum of Rochester son-in-law of Rev. R. C. Brownlee of this place, died on Thursday June 16, of consumption, aged 31 years. Mr. Barnum was a successful lawyer having been admitted to the bar in October 1882. At 21 years of age Mr. Barnum was elected supervisor of the old twelfth ward, serving two terms in the board and being the youngest supervisor ever elected in that county. He declined an almost unanimous call of his constituents to serve them for a third term. In 1868 he was married to Miss Lizzie Adele Brownlee, daughter of Rev. R. C. Brownlee.
Mr. Barnum was a member of the Rochester lodge, F. & A. M., and also Accident lodge No. 163 A. O. U. W. He leaves surviving him his wife and little son, Robert Clinton Barnum, his parents Mr. and Mrs. D. L. Barnum of Wilson, two brothers, Charles Barnum, of Buffalo, and John E. Barnum, of Rochester. The funeral was held from the Asbury church in Rochester on Sunday afternoon.
From the Rochester Chronicle & Democrat, Rochester, NY, June 18, 1892: D. Clinton Barnum, whose death was recorded in yesterday's Democrat and Chronicle, was born at Newberry, Ontario, July 20, 1861, of American parents, who shortly returned to the United States, settling in Wilson, Niagara County, New York. He lived in the village and obtained his education in the Wilson academy. He came to Rochester in September, 1870, and entered the law office of George B. Rinson, where he remained until he was admitted to the bar in October, 1882. He practiced his profession, occupying an office with Charles Allen, until September 1885, when he formed a law partnership with Edward F. Turk, which continued until his death.
At 21 years of age Mr. Barnum was elected supervisor of the old twelfth ward, serving two terms in the board and being the youngest supervisor ever elected in the county. He declined an almost unanimous call of his constituents to serve them for a third term. In 1888, he was married to Miss Lizzie Adele Brownlee, daughter of Rev. R. C. Brownlee. Mr. Barnum was a member of the Rochester lodge F. & A M., and also Occident Lodge. He leaves surviving him his wife and little son, Robert Clinton Barnum, his parents Mr. and Mrs. D. L. Barnum, of Wilson, two brothers, Charles O. Barnum, of Buffalo, and John E. Barnum of Rochester.