- Sanborn Co., Cambridge, Massachusetts1
- Schmid, Germany1
- Schnapper1
- School of Nursing-- Medical College of the State of South Carolina1
- Scientific1
- Scientific Instrument Service1
- Sengbusch1
- Sharp & Dohme1
- Sharp & Smith, Germany1
- Shepard & Dudley, New York, New York1
- Sims, J. Marion (James Marion) 1813-18831
- Smedley's Hydro Co. Limited, Matlock Bank1
- Smithy, Horace Gilbert1
- Spencer Lens Company, Buffalo, New York1
- Stanley and Patterson1
- Storz Instrument Company, St. Louis, Missouri1
- T.C.W. Co., USA1
- Tarnier, S. (Stephane) 1828-1897 Charles Lentz and Sons, Philadelphia, Pennsylvania1
- Taylor Instrument Companies, Rochester, NY1
- Taylor, Benjamin Walter M.D.1