1 July 1797:
Augusta post office opened. (source: Maine Philatelic Society. 1995. The Post Offices of Maine: A Rarity Guide.)
year? August 5:
The cornucopia postmark is approximately 27 mm tall and perhaps 26 or 27 mm wide at the top.
Postmaster: Joseph Burton. (source: Maine Register and State Reference Book. 1852.)
1894 April 16:
The circular postmark is approximately 28 mm in diameter. The elliptical cancellation to the right of the postmark is composed of seven parallel bars with an overall size of approximately 32 mm long and 18 mm wide. Because only one such combination of postmark and cancellation for Augusta has been observed, it cannot be determined if the postmark and the cancellation are joined as a single item.
1894 July 27:
Machine cancellation with a circular postmark of approximately 19 mm in diameter and to the right of the postmark a cancellation of a set of 7 horizontal bars 57 mm long and separated by just under 2.4 mm on center. A numeral is centered in the bars approximately 39–40 mm from their left end.
1895 September 6 through 1895 October 4:
The circular postmark is 24–26 mm in diameter. The elliptical cancellation to the right of the circle is approximately 32 mm tall and 18 mm wide, with 3 bars both above and below the numeral, which is enclosed in a circle. It appears that the postmark and the cancellation are part of the same unit, and that the Augusta post office had at least two such units, one with the numeral 1 and one with the numeral 2.