"slip your revolver into your pocket...."See in text(The Adventure of the Speckled Band)
By bringing Watson’s revolver into the narrative, Doyle evokes the dramatic principle of “Chekhov’s gun.” As Anton Chekhov famously wrote, “If you say in the first chapter that there is a rifle hanging on the wall, in the second or third chapter it absolutely must go off. If it's not going to be fired, it shouldn't be hanging there.” Look for the resolution to the tension of the revolver.
"‘Oh, my God! Helen! It was the band! The speckled band!’ ..."See in text(The Adventure of the Speckled Band)
The term "the speckled band" is used in the title and will be repeated several times throughout the story. The phrase will be one of the most important factors of the plot later on.
"and stared into the crackling fire..."See in text(The Adventure of the Speckled Band)
Note the emphasis on the fire and warmth. This indicates that the weather is very cold outside, a fact that will come into play at the climax of the story.
"It is probable that he will be away all day, and that there would be nothing to disturb you..."See in text(The Adventure of the Speckled Band)
It is "probable" but not certain that the dangerous Dr. Roylott will be "away all day." The uncertainty of Roylott’s whereabouts make the inspection of the rooms at Stoke Moran much more tense. The owner might return and catch Holmes and Watson invading his domain, which, based on Roylott’s characterization would lead to a violent confrontation.
"bending forward and patting her forearm..."See in text(The Adventure of the Speckled Band)
This is unusual behavior for Sherlock Holmes, who shuns displays of emotion. He is probably doing it because he wants to look at her forearm. This will be important to the story later.
"then her sister must have been undoubtedly alone when she met her mysterious end..."See in text(The Adventure of the Speckled Band)
The whole mystery turns on the problem of how Helen's sister could have been killed when she was "undoubtedly alone when she met her mysterious end." This aspect of the locked-room mystery proves most troubling for Holmes.
"not less than £1000 a year..."See in text(The Adventure of the Speckled Band)
That was a very good annual income in Victorian times. Helen Stoner does not say what "annual sum" was to be paid to the girls if and when they married, but she does say that the big house at Stoke Moran "is itself crushed under a heavy mortgage"; so it would be hard for Dr. Roylott to part with a share of the thousand-pounds annual income. This becomes an important part of the story later on.
"In a fit of anger, however, caused by some robberies which had been perpetrated in the house, he beat his native butler to death and narrowly escaped a capital sentence..."See in text(The Adventure of the Speckled Band)
This is an indication of Dr. Roylott's vicious temper, which will be important later in the story.
