scovill 1850s backmark

Hey all, It's been awhile since I last posted. But I have to show off my largest and oldest spill. It is more exciting to find them in my own yard. Woot Woot.. 8 IHP and a Shield nickel.... My property had an old school house on it from 1850 till at least 1900.

I may have dug my oldest Eagle Button to date. The backmark reads "(dot) SCOVILL MFG CO (dot) WATERBURY". The shield is level with the eagle, not raised. Period of manufacture?