Raazor (safety) : K.G. Gillete
Rabies Vaccine : Louis Pasteur
Radar : Dr. A.H. Taylor and L.C. Young
Radio : G. Marconi
Radio transmitter : Alexanderson
Radioactive Dating : Willard Libby
Radioactivity : Marie Curie
Radio-activity of Uranium : Henry Becquerel
Radium : Madame Curie
Railway Engine : Stephenson
Raincoat : Charles Macintosh
Raman effect : C.V.Raman
Rare Gas : Cavandish
Rayon American : Viscose Co.
Razor (electric) : Col. J. Schick
Refrigerator : James Harrison, Alexander Catlin
Replacing human heart : Christian Barnard
Revolution in Chemistry : Antoine Laurent Lavoisier
Revolver : Samuel Colt
Rise of German Science : Hermann von Helmholtz
Rubber (vulcanized) : Charles Goodyear
Rubber (waterproof) : Charles Macintosh