Here's some additional curiosity about Shirley Mills, Maine post office.
It seems the USPS still refers to it as "Shirley Mills" even though the post office signage says "Shirley":https://tools.usps.com/go/POLocator...=20&&&&&&&&&
Note the sign on this photograph shows "Shirley, Maine":
Someone on eBay
is selling a rather beat up postcard showing this post office (circa 1918) at the right side of the card:
Compare it to a more contemporary photograph and the building hasn't changed very much:
And curiously the property (Post Office and General Store) appears to currently be for sale, although in this case it's referred to as in Shirley, Maine, even though it is the same address that the USPS currently lists as Shirley Mills, Maine:http://www.loopnet.com/Listing/1791...-Shirley-ME/
It is described as follows:
Situated on the village of Shirley on quaint Shirley Pond, this well known landmark is the Town's post office and it's only store. The first floor currently houses the general store and post office. On the second floor is space that could be used for cold storage. The post office contract provides a yearly income as well as bringing potential customers into the store. The building offers the charm of yesteryear with its tin ceilings and wood floors.