Sharpen your sluggish brain with 70 specially-commissioned puzzles and challenges devised by Baker Street\047s legendary detective. Sherlock Holmes\047 famous sidekick and longtime friend, Dr John Watson, recounts the mental exercises Holmes conceived for him so that you too can strengthen your facilities for analysis, logic, reason, arithmetic, creative thought and deduction. These cunning puzzles have been grouped by their approximate difficulty but as a wise man once said, "All questions are hard if you don\047t know the answer, and easy if you do."