According to PTAMPIA The Davis Level and Tool Co. was around from 1867 to 1892. This plane was patented in 1875 (Patent no. 167,311). This plane was probably manufactured about 1875 to 1884. It came in 3 sizes, a smoother (9”), a jack (15”) and a jointer (22”). They were manufactured in Springfield MA.
Roger Smith states that most of the bench planes have a Moulson blade. This one has an Ohio Tools. Given the condition of the plane, and the amount the blade has been used, I doubt it’s original to the plane.
An earlier version of the Davis planes featured a scalloped shaped bridge between the side rails. A cutter locking screw is in the center of the bridge and features the screw adjustment feature illustrated in the patent drawings. Later models featured a simplified frog with two round head screws, as shown in picture #4. These planes originally had a Moulson Brothers or Butcher cutter and cap iron.
There is some speculation that the blade is a very early Ohio Tools made by Butcher. If anyone has any insight, I’d love to hear it.