The directions of Barkhausen effects in a single crystal disk of silicon steel, held stationary in a magnetic field rotating slowly in the plane of the disk, have been determined. Search coils at right angles picked up impulses proportional to selected rectangular components of the changes in magnetization. Measurements on an oscillographic record were made at two values of magnetization, 190 and 100. Values of the angle $\phi$ between the change in magnetization $\Delta I$ and the corresponding variation in the applied field, $\left(\frac{\mathrm{dH}}{\mathrm{dt}}\right)\Delta t$ were determined for various positions of the applied field relative to the crystallographic axes. The normal to the disk made angles of 30°, 60°, 90° with these axes. For these low values of magnetization the effects are mainly transverse with respect to $H$ (and therefore nearly parallel to $\frac{\mathrm{dH}}{\mathrm{dt}}$) and are more nearly transverse for the greater value of magnetization. The average value of $\phi$ is about 20° ($\Delta I$ lagging $\frac{\mathrm{dH}}{\mathrm{dt}}$) for the lower value of $I$ and is less than 5° for the higher value. The average magnetization apparently lags the applied field and makes a small angle with it. The direction and frequency of effects seemed unaffected by changing the direction of $H$ in the plane of the disk, so that no dependence upon the crystallographic directions of $I$, $H$ or $\frac{\mathrm{dH}}{\mathrm{dt}}$ have been established.

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