Evidence is presented for the existence of two overlapping dispersions at 20°C in toluene. Resolution of the two dispersions was in terms of separate Debye relaxation processes, with dispersion parameters ε01=2.384, ε∞1=2.269, and τ1=5.80×10−12 sec for the low-frequency process and ε02=2.269, ε∞2=2.222, and τ2=2.0×10−13 sec for the high-frequency process. It is pointed out that it is not precluded that the high-frequency process may in actuality be a resonance absorption. The dielectric constant and loss values were obtained by a free-space method and the results for toluene at 20°C are given for a wavelength range between 9.2 and 2.5 mm. In addition, dielectric constant and loss values for toluene at temperatures of 30°, 40°, and 50°C are reported for wavelengths between 9.2 and 4.0 mm.

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A familiar theorem involving a balance between net torque and rate of change of angular momentum in the electromagnetic field is rederived. This version of the theorem includes the intrinsic torques exerted by the fields on the polarized medium. It is seen that these terms lead naturally to the expression for the intrinsic angular momentum carried by a localized pulse of electromagnetic radiation. In the present treatment the expressions for the external and intrinsic angular momenta arise naturally as separate entities, in contrast to standard treatments, in which both arise out of what is evidently only the external angular momentum.

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