The history of the normal oil field is supposed to show an oil graphstarting high in flush production, descending more or less steeply into thecurve of settled production and dropping gradually to the vanishing point ofeconomical operation. Together with this, somewhere in the early history of thefield, there appears from a vanishing point a graph showing the production ofwater. During the period of settled production this graph rises higher and, toward the close, unless extensive work is done in the line of correction, rises far above the oil graph to the point at which the cost of operationterminates profitable pumping. Fields that start out with a high relativecontent of water are generally very short-lived. Fields that never develop awater problem are exceedingly rare. The McKittrick oil field, Kern County, California, with 840 acres of provedground, 300 wells and a present recovery per acre of 94,598 bbl. from 1898 to Aug. 1, 1930, presents a study which is an apparent reversal of the outlinednormal history. Though the history of the field now covers over 30 years ofoperation, it is still too early and the conditions too unique to project thegraph of production to completion. The present conditions and directions ofchange are most interesting, in that the curve of oil production is remarkablyflat and the curve of water invasion, after reaching an appalling height, hasshown a definite reversal and a continued decline for 10 years. Early drilling in the McKittrick field was in or prior to 1898. Developmentcontinued steadily to 1918 when the present limitations of the field weredetermined. Shut-offs, according to accepted practice of the time, were made bydriving the shoe into a shale stratum or into a tamped-in bridge of sand, rosinand clay. Records of early days speak of three waters:surface water which was fresh;an intermediate sulfur water, encountered below the top oil or tar sand;bottom salt water. In different portions of the field anyone of thesewaters let into a well by faulty completion might require immediate correctionto obtain satisfactory production.