J.T. Slocomb Company

The J.T. Slocomb Company was a renowned American precision tool manufacturer founded in 1891 by John Tibbets Slocomb in Providence, Rhode Island. The firm became famous for inventing the combined center drill and producing exceptionally high-quality outside micrometers featuring patented internal-toothed adjustment sleeves.

More info at

• https://www.practicalmachinist.com/forum/threads/who-can-tell-me-about-j-t-slocomb-micrometers.215709/
• https://progress-is-fine.blogspot.com/2016/12/vanished-tool-makers-jt-slocomb-co.html
• https://www.facebook.com/JTSlocomb/