Measurement of the specific inductive capacity of diamonds by the method of mixtures

The specific inductive capacity of diamonds in bulk has been measured by the method of mixtures, the most accurate single determination being 5.66 at 27.8° C. and 800 c./sec. A general mean value of 5.7 applies within a standard error of 1.5 per cent over the range of temperature from -65° C. to +85° C. and from 300 to 3000 c./sec. and within a standard error of 3.2 per cent for a frequency range from 50 to 5000 c./sec. while no change within a standard error of 2 per cent was observed up to 1.6 Mc./sec. Reasons are given for supposing the present value more accurate than those hitherto obtained, and it is also shown that the value deduced agrees satisfactorily with the refractive index on the basis of Maxwell's law and shows consistency with the relationships of specific inductive capacity to atomic number and the periodic table which hold for other elements. Some observations are made on other physical properties of the diamond and on the theory of the specific inductive capacity of mixtures.