PUZZLE 49

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Across
  1. 3. Hard work (8)
  2. 4. Scientific study of insects (10)
  3. 6. Desert in Chile (7)
  4. 8. Old word meaning to 'break wind quietly' (6)
  5. 10. Most widely used of all solvents (5)
  6. 11. Portico (5)
  7. 13. Learn by research (9)
  8. 19. Also known as an Alligator Pear (7)
  9. 20. Give assent (6)
  10. 21. Novelist who wrote 'From Russia With Love' (3,7)
Down
  1. 1. A female monarch (5)
  2. 2. Orville and Wilbur Wright invention (9)
  3. 5. Move away from home (6)
  4. 7. Silent film star Fatty Arbuckle's real first name (6)
  5. 9. Praise (5)
  6. 12. Send something on its way (8)
  7. 14. Attempt (3)
  8. 15. Spinach-eating sailor (6)
  9. 16. Medicinal mud (5)
  10. 17. Ham, Shem and Japheth were this Biblical character's sons (4)
  11. 18. Imposing height (5)