The cities of the United States have expended $250,000,000 in waterworks and nearly as much more in land for reservoirs, and for canals for conveying the water from these reservoirs to the cities. The better managed systems protect the drained lands from erosion by planting forests or grass and the water is completely controlled, so that all the water, even the storm overflow, is saved. There is very little waste in these city water systems until it comes to the consumer, where, except when it is sold through meters, the waste is often great. The failure to provide the greatest good lies in the fact that the water systems have been used for water supply only and have not been made profitable in other ways. The drainage basins should be heavily planted with trees, which will in time yield a large return, or with hay, which can be marketed each year. Whenever possible, the canals carrying the water supply should also be used to furnish power. The city of Los Angeles, when it had a population of only 150,000, undertook to provide pure water from a point two hundred and fifty miles distant. To do so it must take on itself a debt of $23,000,000, a large sum for a city ten times its size. Yet the people were ready to assume this great burden to insure an unending supply of pure water, for they realized that without it their city could not continue to grow. It was not until the plans for piping water to the city were almost completed that the value of the water-power along the route was realized. It has been disposed of at a rate that pays ten per cent. interest on the debt each year, and has made what seemed a dangerous risk, a profitable business arrangement. All these other uses of water which are profitable, help to lower the price of water to the users. The matter of supreme importance in the water supply, however, is not whether the water is cheap, but whether it is pure. If refuse from factories is allowed to drain into a stream, the water becomes loaded with poisonous chemicals, acids, or minerals. If city sewage or barn-yards are allowed to drain into it, the germs of typhoid and other fevers enter the water supply. To insure the purity of water supply from a stream, no factory waste, city sewage or country refuse should be allowed to enter any part of the stream. In addition to this it should be carefully filtered. The disposal of waste is a serious problem, and the easiest way is to divert it into the nearest water course and trust to the old maxim, "Running water purifies itself."