In answer to a request from the anonymous Rachel:
Sherlock Holmes could be at times the moodiest of men. When no case was upon him, he was prone to the blackest fits of deep depression that ever man fell into.
This was one such day. It was a beautiful balmy spring afternoon, free from the rain that characterises our British Isles, and I had dragged him out-of-doors for a walk, much against his protests.
After an hour of my trying to cajole him into a deducing game with me about people we passed, not succeeding in putting him in a better frame of mind, he finally stopped his grousing to censure me roundly on my incorrect perception.
"Watson, honestly. How many times have I told you, you are a mere conductor of light, not luminous yourself?"
I sighed.
"Multiple times, Holmes."
"Then leave that sort of thing to me, eh? What the devil are you trying to accomplish, anyway?"
"Honestly, Holmes, it doesn't take much of a deduction," I retorted, stung by his words, "to see that I was just trying to get your mind off your failure in the Slane case."
He stiffened.
"How did you –"
He suddenly broke off, the scowl lines in his face slowly relaxing into an affectionate smile, and he slipped his arm through mine.
"And sometimes, Watson, your perception is most startlingly bright."