A device for analog graphic recording of respiration in small animals is described. A two-piece metal band with an inductance coil attached fits around the animal's thoracic region. Movement of a metal core inside the coil causes the inductance of the coil to change, and the voltage across a tuned circuit changes accordingly. The resulting signal is amplified and recorded by an ink-writing galvanometer. The device is simple and inexpensive to construct and easy to use. (Author)
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