Stampless Cover Questions, 1827, Buffalo To Dexter, Michigan Territory

The letter is datelined "Buffalo July 8th 1827". The letter writer states that the letter will be sent with a family heading to Detroit. Now my questions. If the letter was hand carried, why was it marked "Ship" and rated "18 ¾" but not postmarked? Secondly, when the letter arrived in Detroit, why was it postmarked but not re-rated? Since Dexter did not have a post office yet, the letter was probably delivered to Ann Arbor to await pick-up. Thank you.

It was treated as a ship letter when received at the Detroit post office (presumably the letter was turned over to a ship captain as part of the travels).

The Dexter post office opened in 1826.

Thanks for the date correction. Was the captain of the ship paid from the 18 3/4 cents, or was that a separate charge?

The key fact which has not been mentioned is that no ship fee was added to the rate. By Post Office law, since early days, ship captains were not entitled to receive fees if they were under the command of another nation or the US government. So, mail from a Navy ship, or being paid by another government dropped off mail, it had to be noted on the quarterly report as a ship letter but no fee charged.

So, when it entered at Detroit, it was either exempt for the above reason or a mistake.Look in the newspapers online ship arrivals and you may be able to find something that pins that down as one or the other.