Electron microscopic examination of the **f sample showed it to be composed of nearly isotropic particles about 0.3 lm in diameter. The particles appeared rough and undoubtedly the single crystal domains are smaller than this. The x-ray data are consistent with particle sizes of 1000 A or greater. We found no obvious effects due to preferred orientation of the crystallites in this sample nor would we expect to on the basis of the shape found from electron microscopic examination.

The magnetic resonance absorption was detected by employing a Varian model **f broad line spectrometer and the associated 12 -- inch electromagnet system. One measurement at 40 Mc/sec was obtained with the Varian model **f unit. A bridged-T type of bridge was used in the 10 -- 16 Mc/sec range. The rf power level was maintained small enough at all times to prevent obvious line shape distortions by saturation effects. A modulation frequency of 40 cps with an amplitude as small as possible, commensurate with reasonably good signal-to-noise quality, was used. Background spectra were obtained in all cases. The spectrometer was adjusted to minimize the amount of dispersion mode mixed in with the absorption signal.

A single value of the thermal relaxation time **f at room temperature was measured by the progressive saturation method. The value of **f estimated at 470 gauss was **f microseconds. A single measurement of the spin spin relaxation time **f was obtained at 10 Mc/sec by pulse methods. This measurement was obtained by W. Blumberg of the University of California,Berkeley, by observing the breadth of the free induction decay signal. The value derived was 16 microseconds.