One sees watercolors of houses done in this manner in early 19th century school notebooks and I swoon every time I see one. This one I found in Maine in a pile of early 19th century rewards of merit, and I happen to know that is what this one is too. I quickly popped it in this simple wooden frame (probably early 20th c.) to keep it safe, mounted to archival board with archival tape--and would leave it just as is unless one has a terrific period frame lying around! 

Framed: 6 5/8" x 4 11/16". Watercolor, on laid: 2 7/8" x 3 1/4". With a vertical fold line down the center of the watercolor--not separated, but making it fairly delicate.