What is an instrument for measuring the intensity of heat radiating from a fire, or the cooling influence of bodies. It is a differential thermometer, having one bulb coated with gold or silver leaf. [R.] called?

pyroscope — An instrument for measuring the intensity of heat radiating from a fire, or the cooling influence of bodies. It is a differential thermometer, having one bulb coated with gold or silver leaf. [R.]. (Webster's 1913.)

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