US563836 A was granted in 1896. Edison's light bulb dates from 1879, US223898 A.
There is a key idea, namely a parabolic reflector made of glass. Rather than being silvered to reflect light, the parabolic bowl is made with prismatic fluting (triangular ridges) on the outside. Light entering through the smooth inside of the bowl is reflected twice inside one of the prisms, by total internal reflection. Total internal reflection is efficient, and if a little light leaks out it makes the exterior sparkly, rather than totally dark. I think I have seen such reflectors in life.
Years ago I visited the patent office and saw a patent on a simple parabolic reflector as just described. This 1896 patent, US563836 A, seems to be a more complicated version of the idea, presumably invented after the simple version.
As I sit searching on Google Patents, I get the feeling that the simpler patent is not in the Google system, or all the good keywords were garbled by OCR. Does anybody know the simpler parabolic-prismatic reflector patent, from about 1888?? Thank you. I have really struggled with this. My goal is to document a fascinating bit of history.