(under the class definition) Apparatus comprising a tool and a shaft or casing to drive the tool or be driven by the tool, said tool being adapted to be connected to or disconnected from driving relation with the shaft or casing by movement either (1) through the inside of said shaft or casing or (2) externally of the shaft or casing in the space between the
shaft or casing and the bore wall, the movement of the tool being to or from a position below ground while the shaft or casing is in the borehole and without the removal of the latter from the borehole.
SEE OR SEARCH THIS CLASS, SUBCLASS:
23, for device for forming a bore without earth removal in which the drive point is retracted through a shaft or casing.
202, for devices having above ground means for relatively moving below ground tool elements.
236, for devices having a sample receiver with below ground means movable relative to a tool to stop flow toward the bore bottom, the sample receiver being removable through a below ground shaft.
246+, for devices having an undisturbed core receiver which is removable through a below ground tool shaft. 309, for devices having a receptacle removable or insertable through a below ground tool shaft.
