The Adventure of the Speckled Band

by Sir Arthur Conan Doyle

The Adventure of the Speckled Band: Foil 1 key example

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Explanation and Analysis—Sherlock and Watson:

Throughout "The Adventure of the Speckled Band," the reader is presented with the contrasting personalities of Sherlock and Watson. Whereas Sherlock is eccentric and sometimes unpredictable, Watson is level-headed and responsible. Sherlock's deductive abilities are unmatched, while Watson is astounded by the former's discoveries. By positioning Watson as a foil for Sherlock, the story accentuates the latter's extraordinariness. 

This becomes evident early in the story, when Sherlock wakes Watson earlier than usual: 

...I woke one morning to find Sherlock Holmes standing, fully dressed, by the side of my bed. He was a late riser, as a rule, and as the clock on the mantelpiece showed me that it was only a quarter-past seven, I blinked up at him in some surprise, and perhaps just a little resentment, for I was myself regular in my habits.