The subject of this paper will first be defined. The term, Stand-by Charges for Water Works, shall be understood to mean a charge for readiness to serve or stand-by service available to municipalities for fire purposes. Only a few years back little, if any, thought was given to the distribution of costs and rate making in the operation of water works. Generally, those who had to do with the management and operation were interested principally in gross revenue sufficient to pay for the cost of money, operating expense, up-keep, depreciation and, if possible, the establishment of a small reserve fund. To accomplish this the practice was to fix a rate applicable to service rendered to domestic and industrial consumers. Some revenue was derived from a charge for fire hydrants and water used for street sprinkling and sewer flushing. Water works were developed as towns sprung up. Many towns grew fast in population and later on became real cities. The first installation of water works pipe and equipment was, as a rule, only sufficient to take care of the needs at the time. Rapid growth and modern building construction occurred, fire protection had to be provided and those in charge of water utilities endeavored to keep pace with the growth and development and meet the demands made upon them. The increased costs in operation were met by increasing the rate charged for service rendered to domestic and industrial con-