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Excerpt from Electrolytic Corrosion of Iron in Soils The data herein presented represent a portion of the work done by the Bureau of Standards in connection with a more general investigation of the subject of electrolysis and electrolysis mitiga tion, which has been in progress for some time past. The present paper is designed to deal only with the fundamental laws govern ing electrolytic corrosion under practical conditions, and relates to self - corrosion only in so far as it is necessary to distinguish between the two classes. The subject of the prevention of elec trolytic damage is referred to only incidentally, when occasion requires, in order to interpret the significance of results obtained. This matter of electrolysis prevention has been given much atten tion and will be treated at some length in a report which will be issued shortly by the Bureau of Standards, dealing exclusively with the subject of electrolysis mitigation. In studying the phenomena of electrolytic corrosion in soils under practical conditions many variables are encountered which tend in greater or less degree to affect the results. Among these may be mentioned the current density at the surface of the metal, the moisture content of the soil, the presence of oxygen either in the gaseous state or dissolved in soil waters. The latter not only afiects the rate of corrosion but also affects the character of the end products of the reactions, and thus to some extent has a bearing on the question of diagnosing the cause of particular cases of corrosion. The temperature of the soil is also important, par ticularly because of its effect on the current ow. In the case of iron, the formation of oxids as a result of the initial corrosion may complicate matters because of their possible action in stimu lating galvanic action. Other factors, such as the mechanical and chemical properties of the soil, the depth of burial of the metal, the limitation of current ow due to polarization, the formation