All rivers are polluted to a greater or lesser extent. The worst form of pollution is that of crude sewage which is allowed to flow into rivers from towns or villages on the banks; then there is pollution from isolated houses on the banks, privies, refuse heaps, manured fields, sewage farms, etc., and streams which in turn receive refuse and other filth from farms and houses on their banks. The pollution is increased at times of heavy rain and snow, when matter of all sorts is washed into a river. It is important where river water is used for drinking purposes that it should be kept as free from pollution as possible. Sewage from towns or villages and any isolated houses on the banks should be treated before being allowed to flow into a river. In the case of smaller houses where biological treatment would be too costly, and where privies are in use, earth closets should be substituted. Refuse should not be allowed to be deposited on the banks of a river, as during times of flood this material is washed in. At various times outbreaks of typhoid fever have occurred through the contents of privies * A paper readto the Midland Branch of the Society of Medical Officers cff tleahh on February 3rd, z91o.