Surgeon's case

This case contains the type of tools a doctor, such as Conan Doyle, would have used to operate on and treat his patients. 

"He laughed very heartily, with a high, ringing note, leaning back in his chair and shaking his sides. All my medical instincts rose up against that laugh". This is a quote from “The Adventures of the Engineer’s Thumb” published in The Adventures of Sherlock Holmes.