I was told that this wonderful old tin mill came from the Dummer estate in Rowley, MA (more below) and was commissioned by one of the Dummers as a model of sorts of the original colonial era fulling mill on the property--built by John Pearson on the Mill River, and significantly responsible for making Rowley the birthplace of the American woolen industry. It's a bit confusing, as there were several iterations of the fulling mill, and there was also a grist mill nearby, managed by Pearson as well-- all this happening in the 1640s! And then too there were multiple generations of Dummers who had their hands in all of this, at some point purchasing the Pearson Estate and taking over operation of the mills, and in 1763 establishing the Governor Dummer School, which would become the oldest continuously operating independent boarding school in the United States. 

My guess is that this great tin folk art structure--with "FLOUR Mill" written across the front--might be a conflation of several things, or perhaps based on the "Jewel Mill" that in the late 19th century was built on the foundation of John Pearson’s original fulling mill and around that time was operated by the Glen Mills Cereal Company. At any rate, it has some relationship with what is a very rich history and is certainly a very charming thing! Note the very sweet figure drawn in the window and little shoot to the left just below him, as well as the great orange windows on the backside. 

11" tall x 5 7/8" wide x 5 1/4" deep. I would guess early 20th century. The roof comes off and one could store some things inside! The wheel also will come off and perhaps once had something securing the post in place on the other side. It is signed DEAN on the underside.