THE THERMAL CONDUCTIVITY OF SOME REFRACTORIES1

The problem of measuring the thermal conductivity of materials up to high temperatures has been studied, especially in regard to the sources of error. This investigation has shown that many of the previous determinations of thermal conductivity may have had little precision due to a lack of appreciation of the errors involved. The values of thermal conductivity for a number of refractories are given, as obtained by a new type of apparatus designed to eliminate to a considerable extent the errors of measurement. However, it is believed that these values may have an error as high as ± 25 % for the better heat conductors; so there is still much work to be done in developing a method for measuring thermal conductivity with the precision usual in other physical measurements.