Category: Sphygmograph
Estimated Date: 1900
Name: MacKenzie-Lewis Polygraph
Manufacturer: Cambridge and Paul Instrument Co. Ltd

Description: 8 5/8” x 5 1/8” x 4 5/8” mahogany box opens to reveal lid with instructions. Machine mounted in base, there is a windup drive with a speed regulator and paper feed, which has a numbered edge on the paper for reference. A bottle of ink is mounted on the base and there are two pens attached to diaphragms. There are 2 sensors for venous tracings. The sensor for arterial tracing is missing. Rubber tubing present. Serial number L 9348.

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