1. Gunpowder   Otto   Roger Bacon   Andre-Marie Ampere   Dr. Alan M. Turing   Hint Half-n-half Clue   2. Submarine   C. F. Brush   Edmund Cartwright   William Siemens   David Bushnell   Half-n-half Clue   3. Transistor   Bardeen, Shockley, Brattain   Gottlieb Daimler   William Siemens   Christopher Cockerell   Half-n-half Clue   4. Barometer   H. W. Seeley   Dr. Wallace H. Carothers   Gottlieb Daimler   Evangelista Torricelli   Half-n-half Clue   5. Rabies Vaccine   Louis Pasteur   Nikola Tesla   Roger Bacon   Christopher Cockerell   Half-n-half Clue   6. Vaccination   Andre-Marie Ampere   David Bushnell   Edward Jenner   C. F. Brush   Half-n-half Clue   7. Arc Lamp   Dr. William Stokes, Rene Laennec   Alessandro Volta   C. F. Brush   Louis Pasteur   Half-n-half Clue