Delbert Adelmer Barnum was also known as D. A. Barnum. D. Adelmer Barnum and sometimes (incorrectly) with the middle name Adelbert.
From the Otsego Farmer, Otsego County, New York, January 25, 1923: Daniel Adelmer Barnum one of the oldest and most highly esteemed residents of this vicinity passed away quietly and peacefully at his home in Middlefield Center Thursday, January 18th 1923 after an illness of ten weeks from shock. Mr. Barnum was the eldest son of Harry G. and Clarinda (Lent) Barnum and was born on the homestead farm February 18th, 1849. He was twice married. His first marriage to Cora Smith occurred January 11, 1882. She died April 23, 1910. March 8, 1912 he married Miss Alma Mason who survives him and gave him most loving and tender care during his long illness. Mr. Barnum's genial manner won him many friends among the young and older people and he will be greatly missed not only around the home but throughout the entire community. He is survived by the widow abovementioned and one son Lewis by his first wife, two grandchildren and other relatives. Interment in the family plot in the village cemetery.