Mercury-in-glass centigrade thermometer with a range from -20 to +110 degrees. Inscriptions on the white back read “TOTAL IMMERSION” and “ARTHUR H. THOMAS PHILADA USA” and “No. 1” and “PTR 995 1938.” This was probably made in Germany and calibrated at the Physikalisch-Technische Reichsanstalt (Imperial Physical Technical Institute).
Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.