The following simile-
"Swaying to and fro like that of a drunkard.
Presents a terrifying picture of the figures movement.
"Metaphors are also used to very good effect by Conan Doyle. On page
182, Holmes interjects Helens narrative with the comment
"These are very deep waters,"
Holmes clearly sees this as a terrible situation and we can sense that he feels the problem is going to be very difficult to solve.
We can see on page 188 good use of a simile when Conan Doyle Describes the two curved wings of the building as "like the claws of a crab" We get a picture in our mind of the front of the building.
The words and phrases that are used in Watson's introduction such as
'I cannot recall any which represented more singular features than that which was associated with the well-known Surrey family of the
Roylotts of Stoke Morran.' And 'but a promise of secrecy was made at the time, from which I have only freed during the last month….' From this we can see that this case was secrecy. This helps to build up mystery throughout the story.
Roylott was another important character in this story.