1. Thomaes, G., and van Steenwinkel, R., Rev. Sci. Inst., 31, 825 (1960).
2. Thomaes, G., and van Steenwinkel, R., Nature, 187, 229 (1960).
3. Meilhuizen, J. J., and Commelin, C. A., Physica, 4, 1 (1947).
4. Temperature—Its Measurement and Control in Science and Industry, 45 (Reinhold, New York, 1939).
5. For definition, see Hirchfelder, J. O., Curtiss, C. F., and Bird, R. B., Molecular Theory of Gases and Liquids (J. Wiley and Sons, Inc., New York, 1954).