The linearized Boltzmann equation for anisotropic normal metals with weak external magnetic field has been solved approximately by iterational method along the same line as given by Huntington and Chan. A numerical evaluation of the Hall effect coefficients in zinc at high temperature yields values in the two directions Ra and Rc in good agreement with experiment. The components of the effective mass tensor in the lens region (electron like) and the distorted region (hole like) around the slanting reciprocal lattice vectors compensate each other quite closely in the a direction and give a small negative value for Ra. Also, this analysis in terms of the effective mass tensor is able to afford a qualitative understanding of the temperature variation of the Hall effect coefficients.