Across
- 4. it was discovered by Alexander Fleming in 1928
- 6. he invented the electric bulb
- 7. he invented the computer
- 9. invention of some prehistoric genius
- 10. this chemical explosive was invented in China in the 19th century
Down
- 1. they invented paper
- 2. Alexander Bell got the first patent for it in 1876
- 3. he invented the parachute
- 5. at first it was a special form of drawing
- 8. it began with counting of days, months and the cattle