A rare 1881 mechanism which records
the pulse pressure at the wrist. A sensitive manometer sits on the
radial pulse and is amplified by means of a weighted pulley. A
clockwork mechanism turns a roller which winds recording paper under
the needle to record a trace. The box is structurally sound but has
age related wear. The instrument itself is in perfect working order
after 124 years! A fascinating precursor to the ECG /
sphygmomanometer.
