1. Gunpowder   Roger Bacon   Z. Janssen   Kirkpatrick Macmillan   Robert Wilhelm Von Bunsen   Hint Half-n-half Clue   2. Automobiles using gasoline   Sir Frank Whittle   John Napier   Karl Benz   Bardeen, Shockley, Brattain   Half-n-half Clue   3. Ball-Point Pen   James Harrison, Alexander Catlin   Louis Pasteur   John J. Loud   Otto   Half-n-half Clue   4. Refrigerator   James Harrison, Alexander Catlin   Lewis E. Waterman   Sir Isaac Pitman   Z. Janssen   Half-n-half Clue   5. Bakelite   Leo H Baekeland   David Bushnell   G. Ferdinand Von Zeppelin   Dr. Alan M. Turing   Half-n-half Clue   6. Barometer   Bardeen, Shockley, Brattain   Leo H Baekeland   Sir Isaac Pitman   Evangelista Torricelli   Half-n-half Clue   7. Microscope   Z. Janssen   Louis Pasteur   James Harrison, Alexander Catlin   Evangelista Torricelli   Half-n-half Clue