1. Ball-Point Pen   Kirkpatrick Macmillan   John J. Loud   James Harrison, Alexander Catlin   Evangelista Torricelli   Hint Half-n-half Clue   2. Transistor   Dr. William Stokes, Rene Laennec   Bardeen, Shockley, Brattain   Roger Bacon   Louis Pasteur   Half-n-half Clue   3. Printing Press   Johann Gutenberg   James Harrison, Alexander Catlin   Bardeen, Shockley, Brattain   David Bushnell   Half-n-half Clue   4. Automobiles using gasoline   John Napier   Karl Benz   G. Ferdinand Von Zeppelin   David Bushnell   Half-n-half Clue   5. Gunpowder   Roger Bacon   Karl Benz   James Harrison, Alexander Catlin   Dr. Alan M. Turing   Half-n-half Clue   6. Jet Engine   Sir Frank Whittle   Gottlieb Daimler   G. Ferdinand Von Zeppelin   James Harrison, Alexander Catlin   Half-n-half Clue   7. Airship (rigid)   Bardeen, Shockley, Brattain   Otto   G. Ferdinand Von Zeppelin   Leo H Baekeland   Half-n-half Clue