Abstract: An electronic apparatus and method for detecting a quantity of a predetermined substance disposed in a fluid medium. The apparatus includes a probe for contacting the fluid medium and for sensing an electrical condition, such as solution resistance, of the fluid medium caused at least in part by the substance to be detected. There is also included electronic control devices connected to the probe means for generating a signal which is proportional to the quantity of the substance to be detected. The signal is fed to some utilization means, such as a meter, for indicating the amount of substance in solution.

Abstract: An electromagnetic system for more efficiently utilizing energy wherein an outside power source is utilized to rotate a flywheel to a predetermined velocity. A plurality of armatures mounted on the periphery of the flywheel pass through a plurality of magnetic fields generated by stationary coils mounted at radially spaced locations around the rotating flywheel. The magnetic fields are generated by an electric current from a circuit that is so arranged that the magnetic fields are generated and collapsed in time relationship to the rotary movement of the armatures such that, as the armatures approach the magnetic field, they are drawn toward the center of the magnetic field at which point the magnetic field collapses and is regenerated with a reverse polarity so as to repel the armature from the center of the magnetic field whereby the flywheel rotation is maintained at the desired velocity.

Abstract: A display rack for mounting eyeglass lenses, mirrors, and like articles. The display rack has a body panel with integrally formed top and base flanges which, respectively, are adapted to releasably attach the body panel to an upright wall or support the body panel in an upright position on a horizontal surface. In one embodiment of the present invention the body panel is provided with a plurality of arcuately spaced support tabs which are adapted to releasably support a plurality of eyeglass lenses. In a second embodiment of the invention a plurality of vertically spaced and laterally opposed support tabs are provided for slidably receiving an element to be carried by the display rack such as a mirror or a removable support panel on which a plurality of articles are to be displayed.