The thicknesses as finally adopted are practically the same as the recommendations by the British Engineering Standards Association for voltages below 6000 and above this are practically the same as the thicknesses being used by some of the larger English companies. However, one of the latter companies has recently, on the basis of its own experience and on the advice of its consulting engineers, made a further reduction of 25 per cent in the thickness of insulation of cable for 20,000 volts normal operating pressure, the insulation being 300 mils between conductors and 210 mils to ground. The usual British practise calls for a maximum copper temperature of about 50 deg. cent, for transmission cables. Correspondence with English consulting engineers and cable manufacturers shows that their high-voltage cables have about the same dielectric losses as those furnished by the leading manufacturers in this country, that is, if measured at 85 deg. cent, the diele