A heat sensitive cable operable over a temperature range of between approximately -20.degree. F. and 1650.degree. F. The cable includes a tubular metallic sheath which is substantially temperature resistant and moisture impervious. It also includes a mass of compacted insulation material filling the sheath and having an insulation resistance variable with temperature in the range of between approximately 100 and 50,000 ohms. The cable further includes at least one thermoelectric conductor positioned within the insulation material filling the sheath. A method of manufacturing the cable includes the step of preparing the insulation material and advancing the thermoelectric conductor through a given region. It also includes the step of advancing a strip of flat metal material past apparatus for forming and welding a tubular sheath surrounding the given region. The method further includes the step of concurrently depositing the insulation material within the tubular sheath for enclosure and advancing the sheath, insulation material and conductor through apparatus for reducing the diameter of the sheath and applying tension to the conductor. With these steps, the insulation material is compacted and the conductor is positioned within the sheath.