(under subclass 65.1) Devices in which an electric means is used for furnishing information to an observer.
SEE OR SEARCH CLASS
33, Geometrical Instruments,
312, for electrical telemetering of sensed borehole direction or inclination.
175, Boring or Penetrating the Earth,
40+, for processes or apparatus for boring including signaling, indicating, testing or measuring. 250, Radiant Energy,
83+, for ray energy detection or measurement.
324, Electricity: Measuring and Testing,
1+, for apparatus relating to the determination of an electrical characteristic of the subsurface of the earth.
340, Communications: Electrical,
500+, for electrical automatic condition responsive indicating systems.
367, Communications, Electrical: Acoustic Wave Systems and Devices,
25+, for electro acoustic well logging; subclasses 81+ for electro acoustic wellbore telemetering; and subclass 86 for electro acoustic borehole testing.
