Notes:
1840 Census, PA, Dauphin Co, Derry Twp., p. 134
Hummel, Jacob, 38, farmer $700 real estate, b. PA
" , Elizabeth, 34, b. PA
" , Soloman, 11, b. PA
" , Susan, 10, b. PA
" , Jacob, 7, b. PA
" , Mary, 6, b. PA
" , Catherine, 4, b. PA
" , Elizabeth, 2, b. PA
Lehman, Christian, 18, b. PA laborer
1870: Derry, Dauphin, Pennsylvania
Post Office: Hummelstown
John C Landis 30
Mary J Landis 26
Minnie Landis 2
Mary Blouse 16
1880: Hummelstown, Dauphin, Pennsylvania
John C. Landis 39
Mary J. Landis 35
Minnie O. Landis 12
Bessie M. Landis 7
1900: Hummelstown, Dauphin, Pennsylvania
Mary Landix 55, m: 36 yrs, 3 children, 2 living, (John is in an institution)
Minnia O Landix 32, single
Bessie M Landix 23, single
1900: Susquehanna, Dauphin, Pennsylvania
Pennsylvania State Lunatic Hospital (over 880 patients)
John C Landis 59, m: 35 yrs, b: PA/PA/PA, patient
1910: Hummelstown, Dauphin, Pennsylvania
Mary J Landis 65, widowed, 3 children, 1 living
Minnie O Landis, 41, single