The original Mercer County census was submitteed with the surnames in alphabetical order, grouped and sorted by the first letter. Within each letter grouping, names are listed randomly. There was no mention of townships.

In transcribing the census, no attempt was made to replace antiquated or inaccurate spellings with commonly accepted modern spellings. Researchers are advised to look for variations of the spelling, e.g.: Erwin = Irwin; Cack = Keck. The names are transcribed in the order and as spelled in the original census, as accurately as possible. Some pages are dark with faint type. Occasionally, the handwriting is such that letter forms are difficult to discern. The pages lack horizontal lines; reading the rows of numbers can sometimes be difficult. Occasionally, the original census writer seems to have also become confused, as the rows are neither straight nor even. Although I have made a good faith effort to reproduce the census as accurately as possible, I cannot guarantee that this transcription is faultless. A question mark [?] indicates that my reading may not be accurate. Gaps (---) indicate illegibility.

NOTE: From 1800 until 1804, the Crawford County government had legal jurisdication over Mercer County. In 1850, the southern portion of Mercer County was given to the newly created county of Lawrence.