Abstract: Geophone detectors are spaced along a long borehole in a mineral seam by pumping grout from a grout tank into a breech assembly and selectively passing the detectors from the breech assembly through gate valves and into a drill string inserted in a borehole. The detectors are connected by a trailing signal cable and an anchor module secures the cable at the far end of the borehole. The detectors can be orientated in the borehole before the grout sets them in position.

Abstract: Geophone detectors are spaced along a long borehole in a mineral seam by pumping grout from a grout tank into a breech assembly and selectively passing the detectors from the breech assembly through gate valves and into a drill string inserted in a borehole. The detectors are connected by a trailing signal cable and an anchor module secures the cable at the far end of the borehole. The detectors can be orientated in the borehole before the grout sets them in position.

Abstract: A telemetry system for borehole drilling comprises an effectively continuous length of hardwire cable which extends along a drill string located in a borehole between electrical signal control, indication equipment situated outside the borehole and probe means situated within the borehole. The effective continuous length of hardwire includes a store of hardwire constituted by a bonded wound hollow coil of hardwire located adjacent the probe means.

Abstract: A drill pipe section enables electrical information signals to be transmitted along a borehole to feed information generated by instruments situated adjacent to the drilling bit along the drill string to monitoring and/indication equipment situated adjacent to the drilling machine. The section comprises a generally cylindrical housing member and a liner member fixedly mounted inside the housing member with an air gap defined between the two members. An electrically conductive element extends between two electrically conductive, annular coupling components one of which defines a radially inwardly directed coupling margin and the other of which defines a radially outwardly directed coupling margin.

Abstract: A flexible information storage disc includes a central mounting portion and an outer body portion providing a surface area on which information may be recorded. The central mounting portion is provided with a least first and second apertures disposed radially outwardly with respect to the geometric center of the disc. The first and second apertures are respectively arcuately elongated in directions conforming to rotation of the disc about its geometric center. The leading end of the first aperture is defined by a pair of straight edges angularly intersecting at an apex and the leading end of the second aperture is defined by a single straight edge.