S. Shaw, Lancashire, United Kingdom, "Mackenzie's Ink Polygraph", clockwork motor for the feed of paper tape and time interval marking, diaphragm receivers with and without leather straps, two ink pens, and other accessories, all in a fitted velvet-lined
The leather covered case is deteriorating on the top. The inside of velvet-lined box is in good condition. The machine is not entirely complete as it is missing the bracket to hold the paper roll, and perhaps also some other accessories. Set comes with four recording diaphragms or "tambours" as Mackenzie called them. Small dried samples of the original rubber tubing are included. The included paper roll is presumably an actual polygraph recording taken by the machine and dated 1918. The machine was invented by the famous heart surgeon Sir James Mackenzie (1853-1925). In use, one diaphragm is placed over a vein in the neck and another over the wrist. Movements of the blood in these locations cause the diaphragms to vibrate. The vibrations were carried via rubber tubing to the long recording pens which were set to just barely touch a paper roll that was advanced by the spring driven motor. The clockwork mechanism is still capable of performing its two functions: turning the paper feed roller and impulsing the time-marking pen on one the end of the unit. This early polygraph was one of the first that could display heart irregularities in a visual manner. They were also used as lie detectors. Dimensions are for the carrying case.
Clock types
