The advent of low temperature superconductors in the early 1960's converted what had been a laboratory curiosity with very limited possibilities to a prac- tical means of fabricating electrical components and devices with lossless con- ductors. Using liquid helium as a coolant, the successful construction and operation of high field strength magnet systems, alternators, motors and trans- mission lines was announced. These developments ushered in the era of what may be termed cryogenic power engineering and a decade later successful oper- ating systems could be found such as the 5 T saddle...