It is postulated that water quality is a primary factor in corrosion by fresh waters, especially at low velocities, and that the influence of dissolved oxygen and pH on corrosion rates is secondary. Citing classic articles on pH adjustment, the authors say the conclusions reached by cited experiments are true only for the water tested and cannot properly be applied generally to all waters. By means of an electrolysis cell the authors tested the effect on anodes and cathodes of passing through water moving at various low velocities an increasing volume of current and noted changes in the character of the water.