### Clue: Dig up Algernon's useful invention (not the first) (6)
### Answer: UNBURY 
 ### Explanation: Dig up Algernon's useful invention (not the first) (6)
(b)**UNBURY**, Algernon's imaginary friend in Wilde's *The Importance of Being Earnest*, used as a ruse to get out of unpleasant social engagements.