CHEMISTRY 1427 1. Water having a history of recent recovery from, phenolic pollution (B.O.D. due to sewage over 3 p.p.m.) 2. Sewage-polluted water, B.O.D. over 3 p.p.m. 3. Relatively pure water, B.O.D. under 1 p.p.m.scientific aide, assisted in the analysis of the residual phenolic compounds in many of the experiments.