In the 1880 US Census for Allenport, Washington County, Pennsylvania the family of Jesses Duncan Barnum was enumerated as follows:
Dwelling #91; Family #104
Barnum, J.D.; White; Male; 45; Married; Coal miner; Unemployed 6 months during the census year; b. Pennsylvania; Both parents b. Pennsylvania
Barnum, Elizabeth; White; Female; 41; Wife; Married; Keeping house; b. Pennsylvania; Both parents b. Pennsylvania
Barnum, Samuel; White; Male; 15; Son; Single; At school; b. Pennsylvania; Both parents b. Pennsylvania
Barnum, Adda [sic]; White; Female; 12; Daughter; Single; At school; b. Pennsylvania; Both parents b. Pennsylvania
Barnum, Allen P.; White; Male; 11; Son; Single; At school; b. Pennsylvania; Both parents b. Pennsylvania
Barnum, Francis; White; Male; 7; Son; Single; b. Pennsylvania; Both parents b. Pennsylvania
Barnum, Harry; White; Male; 2; Son; Single; b. Pennsylvania; Both parents b. Pennsylvania
According to his obituary, published in Fayette City, Pennsylvania, Jesse died at home in Allenport, Pennsylvania of complications of disease. At the time of his death, he was associated with the Allenport Coal Company, which operated the Clipper Mine. He was a member of the Masonic Lodge of Fayette City (Gummert Lodge No. 252), which he had joined on 16 September 1866. He was the Grand Master of that lodge in 1879. Prior to 1866 he had been a member of Lodge No. 344 in Wenona, Illinois. At his death, he left a widow and six children.