Abstract: A hole is formed in soil by penetrating it with a tool comprising a shaft having a tapered point or auger of relatively small cross section attached to its lower end, and a series of outwardly pressing rams mounted on the shaft above the tapered point. The rams are effective successively to enlarge incrementally by outward compaction or displacement of the soil, the hole initially formed by the tapered point or auger. Full hole dimension above the tool is maintained by reason of the fact that the soil is incrementally compacted and compressed to resist collapse. If desired, the integrity of the hole may be preserved with the aid of a following shield, or the hole may be filled with soil stabilizing fluid such as drilling mud. After formation of the hole, the tool is withdrawn and the hole may be filled with concrete to form a load supporting column or it may be left as an open shaft.The method and apparatus may also be used to enlarge the diameter of an existing hole.