Abstract: A method of forming a row of concrete piles in ground is disclosed wherein it is possible to position piles sufficiently close that additional concrete shoring on either side or between piles is unnecessary. A hole for a pile is first bored, the ground forming the hole is hardened and thereafter filled with concrete. This process is repeated for subsequently drilled holes until the row is completed. A drill is also disclosed which includes jet means to force ground hardening liquid under high pressure into the ground surrounding the hole. The jet means may be rotatably and/or axially moveable within the hole.