Category: Sphygmomanometer
Estimated Date: 1920
Name: Blutdruckmesser (Tonometer), Erbes Spezialmodell
Manufacturer: C. Erb

Description: 4.75“x 4.75” x 1.5” wooden box with 3.75” circular dial behind glass. Labeled as above,with scales for mercury and water, to 300 and 400 respectively. The box has two inlets for connection of tubing at top and a knob to adjust the zero. A lacquered brass rod in the back is hinged to fold out and serve as a support so the box is upright at about 75 degrees. The cover is held in place by four screws.

Reference 1: 46