A HOUSEHOLD electricity supply installation in the simplest form and on a small Apale the power systems, the control of which is described in the book under review. In the case of the household model in Britain there is usually only one source of supply. Its capacity is of the order of 5 kilowatts at 230 volts. It is subdivided at a distribution box from which circuits of about 1 kW. capacity radiate to the different parts of the premises and supply lights, radiators, cookers, power plugs and the like. Each circuit is controlled by a simple hand-operated switch, and provision in the form of fuses is made for automatically disconnecting circuits which become faulty. All apparatus and wiring is well protected against mechanical damage so that faults are infrequent. Electric Power System Control By H. P. Young. (Monographs on Electrical Engineering, Vol. 11.) Second edition, revised and enlarged. Pp. xii + 369. (London: Chapman and Hall, Ltd., 1946.) 25s. net.