Abstract: An ink composition or system for writing instruments constructed with a polyester fiber reservoir and a porous oriented fiber nib. This ink system will write on both black and white surfaces. On black surfaces, it will reveal itself as being opaque and metallic almost iridescent in appearance. On white surfaces, a tint of color is observed with distinct flecks of silver. The ink system is composted of water as a carrier, a permanent water-based binder, a colored pigmented permanent water-based dispersion of sub-micron particle size, a unique aluminum dispersion of specific particle size in a special carrier, a humectant, a surfactant that lowers surface tension, an anti-settling additive, a preservative and a base acting as a pH adjuster.

Abstract: An ink composition or system for writing instruments constructed with a polyester fiber reservoir and a porous oriented fiber nib. This ink system will write on both black and white surfaces. On black surfaces, it will reveal itself as being opaque and metallic almost iridescent in appearance. On white surfaces, a tint of color is observed with distinct flecks of silver. The ink system is composted of water as a carrier, a permanent water-based binder, a colored pigmented permanent water-based dispersion of sub-micron particle size, a unique aluminum dispersion of specific particle size in a special carrier, a humectant, a surfactant that lowers surface tension, an anti-settling additive, a preservative and a base acting as a pH adjuster.

Abstract: An ink composition or system for writing instruments constructed with a polyester fiber reservoir and a porous oriented fiber nib. This ink system will write on both black and white surfaces. On black surfaces, it will reveal itself as being opaque and metallic almost iridescent in appearance. On white surfaces, a tint of color is observed with distinct flecks of silver. The ink system is composted of water as a carrier, a permanent water-based binder, a colored pigmented permanent water-based dispersion of sub-micron particle size, a unique aluminum dispersion of specific particle size in a special carrier, a humectant, a surfactant that lowers surface tension, an anti-settling additive, a preservative and a base acting as a pH adjuster.

Abstract: A seismic detector assembly is disclosed that includes a housing and a seismic detector or geophone located in the housing. The geophone has a pair of external terminals that are positioned asymmetrical to the longitudinal axis of the geophone. A printed circuit board having conductive strips for connecting the terminals to leader cables is located in the housing above the geophone. The printed circuit board has a pair of asymmetrical openings through which the asymmetrical terminals can extend only when the printed circuit board is oriented in one position relative to the geophone. Marks on the printed circuit board indicate which conductive strip should be connected to which terminal and the proper orientation of the printed circuit board relative to the truck that receives the output of the geophone.

Abstract: A seismic detector housing assembly is disclosed having a housing open at one end, a seismic detector having an outer case with generally flat end walls, and a pair of terminals extending out of the case through one end wall located in the housing with the terminals extending outwardly from the open end of the housing. A seal member of elastomeric material having openings, through which the terminals extend, covers the end of the detector and closes the open end of the housing. A PC board for connecting the terminals to leader wire conductors covers the seal member. A cup-shaped cap is attached to the housing to enclose the terminals and an outer edge to engage the PC board and compress the seal member into sealing engagement with the cap and the housing.

Abstract: Disclosed is test apparatus included in a cable transmission system having intermediate local data units spaced along a cable, one connection to the cable also being to a master or control station. At each data unit, there is an input differential amplifier with two input terminals for application of at least one local data signal. A test signal is applied to the data unit via a transmission connection from the master station to a first element of a voltage divider connected to one of the two input terminals of the differential amplifier. A switch at the data unit is connected for disconnecting the data connection from the other input terminal of the differential amplifier. A second switch at the data unit, provides a connection to a conductor leading to the master station for connecting earth ground to the data unit local circuit common.

Abstract: The invention disclosed includes a takeout connector having a body of elastomeric material with first and second protruding cylindrical portions. A male plug and a female socket in side-by-side relationship in each cylindrical portion. The second cylindrical portion has a cavity to receive a first cylindrical portion of another connector to allow the connector to be electrically connected to two similar connectors.

Abstract: A spring for a geophone has a plurality of spring arms connecting inner and outer concentric annular portions to resiliently resist relative movement of the annular portions along the concentric axis. Two support arms are connected to each spring arm. Each support arm has one end connected to one of the annular portions and the other end connected to the spring arm at a point spaced from the point of connection of the other spring arm to increase the natural frequency of the spring in a direction lateral to the concentric axis without changing appreciably the natural frequency of the spring along the concentric axis.