The coercive force of Dy single crystals has been measured at low temperatures using both D. C. and A. C. methods to verify the predicted intrinsic coercive force. The coercive force was found to depend upon the field sweep rate, increasing monotonically with sweep rate, but reaching a maximum (intrinsic) value above a certain sweep rate. The observed intrinsic coercive force is in a good agreement with theory, both in magnitude and in temperature dependence.