During recent years, oil producers have observed with interest the practicalsuccess which has attended the application of water as a medium fordisplacement of oil from its reservoir sands in the Bradford field of northernPennsylvania and southern New York. Here, according to various authorities, additional recoveries of from 2,000 to 12,000 bbl of oil per acre have beensecured by this method, after ordinary flowing and pumping methods ofproduction had practically reached the lower limit of economic operation. Notwithstanding the success which has attended the practical use of theflooding process in the Bradford field, oil producers in other regions areskeptical of its value when applied under physical conditions differingmarkedly from those which characterize the Bradford field. Its use wouldprobably be construed as illegal in most of the oil-producing states. Thisgeneral reluctance on the part of oil producers in other regions to accept theflooding process is due in large part to lack of information regarding thefactors that influence its operation and efficiency. With the purpose of clarifying to some extent the issues involved, and ofdetermining when the flooding process may or may not be effectively employed, the writers have conducted as series of laboratory experiments under carefullycontrolled conditions, designed to indicate the influence of various physical, chemical and lithologic factors.