Dear Mr. Kelly,
Thank you for posting your request on History Hub!
In addition, we searched ArchiveGrid and located 4 sources for the search “Baldwin Mills AND Massachusetts”. ArchiveGrid includes over 5 million records describing archival materials,from over 1,000 different archival institutions to assist researchers looking for primary source materials held in archives, libraries, museums and historical societies.
We hope this is helpful. Best of luck with your research!