Spring-Loaded Pressure Probe in Case Thin, metal spring-loaded pressure probe in brown case. Probe marked with a scale (0-300), the maker's name "R. DÉTERT GR" and the code "G.R.G.M. 70441". The lid of the case is inscribed "Federnde Drucksonde n. Geh. Rat Lucae" in golden lettering. [1875-1925]