Residents of Marmora, Lake — Sub-district F, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 19 | obrien | edward | M | 25 | Roman Catholic | Irish | Ontario | Miners | 301 |
| 16 | obrien | margaret | F | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 17 | obrien | mary | F | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 14 | obrien | patrick | M | 30 | Roman Catholic | Irish | Ontario | Cooks | 281 |
| 15 | obrien | sophia | F | 24 | Roman Catholic | French | Ontario | No Occupation Listed | 281 |
| 15 | ohara | dominick | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 114 |
| 8 | ohara | james | M | 55 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 114 |
| 14 | ohara | james | M | 15 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 114 |
| 11 | ohara | jane | F | 23 | Roman Catholic | Irish | Ontario | No Occupation Listed | 114 |
| 10 | ohara | john | M | 25 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 114 |
| 13 | ohara | margaret | F | 19 | Roman Catholic | Irish | Ontario | No Occupation Listed | 114 |
| 9 | ohara | martha | F | 45 | Roman Catholic | Irish | Ireland | No Occupation Listed | 114 |
| 12 | ohara | philip | M | 21 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 114 |
| 2 | omealey | anthony | M | 16 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 113 |
| 5 | omealey | edward | M | 10 | Roman Catholic | Irish | Ontario | No Occupation Listed | 113 |
| 4 | omealey | ellen | F | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 113 |
| 25 | omealey | james | M | 20 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 113 |
| 23 | omealey | johana | F | 44 | Roman Catholic | Irish | Ireland | Female farmer | 113 |
| 6 | omealey | johana | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 113 |
| 7 | omealey | john | M | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 113 |
| 24 | omealey | mary | F | 24 | Roman Catholic | Irish | Ontario | No Occupation Listed | 113 |
| 1 | omealey | patrick | M | 18 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 113 |
| 3 | omealey | william | M | 14 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 113 |
| 21 | oneill | ellen | F | 31 | Roman Catholic | Irish | Ireland | No Occupation Listed | 225 |
| 24 | oneill | james | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 225 |
| 20 | oneill | john | M | 46 | Roman Catholic | Irish | Ireland | Miners | 225 |
| 22 | oneill | john | M | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 225 |
| 23 | oneill | mary | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 225 |
| 4 | osborne | alice | F | 11 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 10 | osborne | beatice | F | 1 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 3 | osborne | benjamin | M | 13 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 6 | osborne | daniel | M | 8 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 24 | osborne | emely | F | 19 | Methodist | English | Ontario | Servants nfs | 158 |
| 25 | osborne | frank | M | 17 | Methodist | English | Ontario | Labourers nfs | 158 |
| 9 | osborne | gertrude | F | 3 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 23 | osborne | harriet | F | 41 | Methodist | English | England | No Occupation Listed | 158 |
| 5 | osborne | harriet | F | 10 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 7 | osborne | henry | M | 6 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 22 | osborne | james | M | 42 | Methodist | English | England | Miners | 158 |
| 1 | osborne | james | M | 16 | Methodist | English | Ontario | Labourers nfs | 158 |
| 8 | osborne | mable | F | 4 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 2 | osborne | sarah | F | 15 | Methodist | English | Ontario | No Occupation Listed | 158 |
| 22 | osler | agnes | F | 25 | Methodist | Scottish | Scotland | Dressmakers | 267 |
| 20 | osler | david | M | 51 | Presbyterian | Scottish | Scotland | Miners | 267 |
| 3 | osler | elizabeth | F | 9 | Methodist | Scottish | Quebec | No Occupation Listed | 267 |
| 24 | osler | euphemia | F | 17 | Methodist | Scottish | Quebec | No Occupation Listed | 267 |
| 2 | osler | hannah | F | 11 | Methodist | Scottish | Quebec | No Occupation Listed | 267 |
| 1 | osler | james | M | 12 | Methodist | Scottish | Quebec | No Occupation Listed | 267 |
| 4 | osler | james | M | 7 | Methodist | Scottish | Quebec | No Occupation Listed | 267 |
| 23 | osler | jennett | F | 19 | Methodist | Scottish | Quebec | Servants nfs | 267 |
| 21 | osler | mary | F | 45 | Methodist | Irish | Quebec | No Occupation Listed | 267 |
| 6 | osler | sarah | F | 2 | Methodist | Scottish | Ontario | No Occupation Listed | 267 |
| 25 | osler | susan | F | 13 | Methodist | Scottish | Quebec | No Occupation Listed | 267 |
| 5 | osler | thomas | M | 5 | Methodist | Scottish | Ontario | No Occupation Listed | 267 |
| 9 | outwaters | john | M | 47 | Methodist | Welsh | Ontario | Tinsmiths and Tinners and Tinkers | 242 |
| 10 | outwaters | nancy | F | 38 | Methodist | German | Ontario | Weavers | 242 |