The Flashlight: Dry Cells, a Small Lamp and a Thumb Ring

"The invention consists in the way of assembling the parts and in the manner of making the electrical connections". The casing A "is a cylindrical tube, being shaped somewhat like a policeman's club, and is shown as formed of pasteboard." At one end is a bull's-eye: a lens B and a parabolic reflector C, "the lamp D being screwed into the base of the reflector." The lamp is "a small incandescent lamp of ordinary construction", one end of the filament joined to the threaded band F and the other to a button G. "A dry battery is used, composed of cells H, placed end to end", inside a pasteboard tube M. One pole meets the lamp's button; the other a metal rear cover N with a contact spring O. The circuit runs by a wire Q to a metal ring R, which "is normally held out of contact with the band T by means of a spring N' and must be pressed in contact against the force of this spring. The ring is a convenient thumb-contact." "The circuit is always open except when the light is actually needed." Pushing on the cover presses both poles of the battery firmly home, "insuring good contacts at both poles and preventing shaking of the battery-cells." A second figure fits the same handle with a glowing platinum wire as a gas-lighter.

Roll a tube from card around two AA cells and tape it. Fit a battery holder with a switch, a small torch bulb in a socket at one end, and a reflector cut from the inside of a drinks can or a spoon polished bright, with the bulb at its focus. Put a disc of clear acrylic over the front. Shine it at a wall 2 m away, measure the bright spot's diameter, and work out the beam angle; slide the bulb forward and back to find the narrowest beam. Time how long it runs on fresh cells with the multimeter watching the voltage.

**David Misell** of New York, a British subject, assignor to **The American Electrical Novelty and Manufacturing Company**, filed US 617,592 on 12 March 1898; it is dated 10 January 1899. **Honest limits.** Cell capacity, lamp current, focal lengths and filament sizes in the notebook are examples; dry cells of the 1890s held much less than modern ones.