Obtaining large undisturbed soil-cores in metal and transparent cylinders

Water-spreading for the purpose of increasing the ground-water supply has been practiced to a limited extent in southern California in natural river-channels and on debris-cones and fans where soils are composed primarily of sands, gravels, and cobbles. In the San Joaquin Valley, spreading is contemplated on the valley-floor between the major stream-channels. Here the soils are loamy sands and sandy loams belonging to several soil-series. Some are older alluviums having a hardpan substratum.