The Adventures of Sherlock Holmes.

EXCERPT: 

“You see, but you do not observe. The distinction is clear. For example, you have frequently seen the steps which lead up from the hall to this room.”  “Frequently.”  “How often?”  “Well, some hundreds of times.”  “Then how many are there?”  “How many? I don’t know.”  “Quite so! You have not observed. And yet you have seen. That is just my point. Now, I know that there are seventeen steps, because I have both seen and observed. By the way, since you are interested in these little problems, and since you are good enough to chronicle one or two of my trifling experiences, you may be interested in this.” He threw over a sheet of thick, pink-tinted notepaper which had been lying open upon the table. “It came by the last post,” said he. “Read it aloud.”  The note was undated, and without either signature or address.  “There will call upon you to-night, at a quarter to eight o’clock,” it said, “a gentleman who desires to consult you upon a matter of the very deepest moment.