German blood pressure monitor circa 1915. An aneroid Sphygmomanometer meter (for taking the blood pressure). German model Tonometer after Dr. von Recklinghausen, from the beginning of the 20th century. It was produced by Med. Warenhaus Akt. Ges. Berlin It includes a pressure measurement scale in units of mm mercury in the course 4 to + 300, also a scale in units of centimetres of water in a range 5 to + 400. The scale dials can be turned 360 ° , so the device can be set to zero. The device comes in its original wooden box, diameter of 12 cm, together with two early 20th-century brown glass pharmacy bottles with glass stoppers and labels, length 25 cm