| 1840 FERGUSON Index | ||||
| Last | First | Census | Location | Census |
| Name | Name | State | (County; Town) | Year |
| Furgason | Mary | DC | Alexandria; Alexandria | 1840 |
| Ferguson | ?? | DC | Washington; Washington | 1840 |
| Ferguson | Dennis | DC | Washington; Washington | 1840 |
| Furgason | James | DC | Washington; Washington | 1840 |
| Ferguson | John | DC | Washington; Washington | 1840 |
| Furgason | John | DC | Washington; Washington | 1840 |
| Furguson | John B | DC | Washington; Washington | 1840 |
| Ferguson | Joseph | DC | Washington; Washington | 1840 |