Derivatives witb respect ta cone semi-angle and free-stream Mach number are presented for fight of tbe flow field quantities tabulated in Reference 1 for the case of supersonic flow of an ideal gas (y = 1. 400) about circular cones at zero incidence. Tbe derivatives may be used in a first-order expansion ta comp.tte the essential properties of tbis flow at the shock wave and at tbe surface of cones of any semi -angle and at any free-stream Mach number within tbe range treated in Reference 1. An account is given of the methods used ta obtain these derivatives