Hall coefficient for sputtered films of gold was determined for films varying in thickness from about 10 mμ to 80 mμ, and was found to be independent of the current (even though current densities up to ${10}^6$ amp./${\mathrm{cm}}^2$ were used), of the magnetic field (3 to 28 kilogauss), and of the thickness (computed from the surface density), and of previous treatment of the film, and to have the same value as for bulk metal, 643×${10}^{-6\mathrm{}}$. This is accurate to one per cent since the high current densities used gave e.m.fs. of over a milli-volt. The constancy of the coefficient agrees with the theory that the sputtered particles have individually the same properties as the bulk metal.

Specific resistance of sputtered films of gold is erratic for films less than 10 mμ thick, but for thicker films is proportional to $\frac{\rho }{(\sigma -{\sigma }_0)}$ where $\sigma$ is surface density and $\rho$ is the density. The specific resistance $r$ came out about 3 times the value for bulk metal. The high value is doubtless due to poor electrical contact between particles. From the value of the constant ${\sigma }_0$, 20×${10}^{-6\mathrm{}}$ gm/${\mathrm{cm}}^2$, the average size of the particles is of the order of ${10}^{-6\mathrm{}}$ cm.

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