1. Refrigerator   James Harrison, Alexander Catlin   Sir Frank Whittle   Robert Wilhelm Von Bunsen   John Napier   Hint Half-n-half Clue   2. Electric Motor (AC)   Louis Pasteur   John J. Loud   Dr. Wallace H. Carothers   Nikola Tesla   Half-n-half Clue   3. Automobiles using gasoline   Bardeen, Shockley, Brattain   Lewis E. Waterman   Robert Wilhelm Von Bunsen   Karl Benz   Half-n-half Clue   4. Stethoscope   Dr. William Stokes, Rene Laennec   Louis Pasteur   Alessandro Volta   Sir Isaac Pitman   Half-n-half Clue   5. Shorthand   Roger Bacon   John J. Loud   Sir Isaac Pitman   Evangelista Torricelli   Half-n-half Clue   6. Bicycle   Kirkpatrick Macmillan   Evangelista Torricelli   Edward Jenner   Edmund Cartwright   Half-n-half Clue   7. Ball-Point Pen   Lewis E. Waterman   James Harrison, Alexander Catlin   Otto von Guericke   John J. Loud   Half-n-half Clue