ESDU 70010@ which is one of a series of four@ presents data for the Mach number along a streamline in the conical flow field between the shock and the surface of a sharp-nosed right-circular cone at zero incidence in a uniform@ inviscid@ supersonic airflow. The variations through the conical flow field of the Mach number increment above the cone surface value are given for upstream Mach numbers increasing from the shock detachment value to a value of 4 for cones with semi-vertex angles of 5@ 10@ 15@ 20@ 25@ 30@ 40 and 50 degrees. Also given@ in carpet form@ for the same range of Mach numbers and cone semi-vertex angles@ are data for the Mach number on the cone surface. The data were obtained from an exact solution of the conical flow equations.