New Incandescent Lamps for Desks
The following is a short article published in 1891 on a new desk lamp:
"In the accompanying illustration is shown a new form of incandescent lamp, specially devised for desks, that is placed on the market by the Central Electric company of Chicago. This lamp differs somewhat in shape from the ordinary incandescent lamp, its sides being almost straight, while the bottom or large end is as nearly flat as possible. The advantage claimed for this form of lamp is that the straight lines provide better reflecting surfaces and prevent as much as possible, uneven intensities of light upon the object. The inside of the butt and the outside of the globe are silvered, and the incandescent filament is actually surrounded on three sides by a mirror reflecting all of the light downward. While the lamp may be placed on a level, or a little above the level of the eye, no light strikes the eye directly from the lamp, as the silvering is covered and protected by an opaque substance. The lamp is made to fit any socket."
Reference
1) "New Incandescent Lamps for Desks", Western Electrician, Vol 8, No 16, Apr 18, 1891, pg 224.