Happy birthday!

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Across
  1. 3. 22nd 1910, Invented the first freely programmable computer
  2. 8. 4th 1910, Invented the Hovercraft
  3. 12. 7th 1811, Discovered anaesthetic properties of chloroform
  4. 18. 9th 1781, First steam train
  5. 19. 10th 1913, First hired employee of Social Security System
  6. 20. 27th 1880, First deaf bbind person to earn a BA
  7. 21. 22nd 1887, Founding member of World Wildlife Fund
Down
  1. 1. 26th 1902, Invented jets and eight-track tape
  2. 2. 18th 1944, Pioneer in the development of computer music languages
  3. 4. 7th 1843, Invented kindergarten
  4. 5. 11th 1867, Discovered ozone layer
  5. 6. 8th 1916, Co-discovered DNA structure
  6. 7. 3rd 1947, A pioneer of computer special effects
  7. 9. 12th 1851, Invented spark plugs
  8. 10. 5th 1915, Founded MENSA
  9. 11. 23rd 1943, American inventor of internet protocol
  10. 12. 17th 1867, Irish inventor of shorthand
  11. 13. 10th 1908, Invented a manufacturing process for penicillin making it available as a medicine
  12. 14. 14th 1925, Invented Land Rover
  13. 15. 8th 1955, Led development of World Wide Web
  14. 16. 9th 1915, Electric guitar
  15. 17. 1st 1957, Invented Palm Pilot and Treo