Category: Misc. Diagnostic
Estimated Date: 1930
Name: Electrocardiograph
Manufacturer: Cambridge Instrument Company

Description: Wooden case contains a string galvanometer with magnets in housing , knob to adjust string. Light shines through housing to enter a box containing light sensitive paper. A mirror refects a scale i to the box as well and paper advances into a drum which can be closed and removed. there is a counter. Pat date 1911 and gear mechanism to advance paper and counter and a timer wheel.

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